The role of observation [Archive]

Mike Helland

Jun16-04, 03:56 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\nIn the two main theories of physics (relativity and quantum) the role\nof observers or observations seems to be pretty important.\n\nIs there text available that rigourously defines these concepts?\n\nSpecifically I would like to know if the established thinking is that\nonly a human being may observe. This seems to be a common belief I\nsee. Is this supported by any hypothesis or literature?\n\nIf nature is viewed as an evolving system wherein agents are involved\nin interactions, what role in this system does "observer" or\n"observation" play that is not adequately fulfilled by "agent" or\n"interaction"?\n\nIt seems to me that "observation" only describes a level of\nsophistication involved in the interaction. For example, consider\nparticles in a tree interacting with particles in my eye. This\ninteraction occurs even if I\'m lieing on the ground dead. The\ndifference is that when I\'m dead my nerves and brain do not react the\nsame way as when I\'m alive.\n\nThese actions by my nerves and brain are really nothing more than\nseveral additional levels of the same types of interactions in a\ncomplex network. The interactions of a living human being are more\nsophisticated than other interactions by non humans, and I think this\nis why we call our sophisticated interactions "observations."\n\nI think the important question is then:\n\nIs this sophistication really relevent in our formulating of physical\ntheories about the fundamentals of the universe?\n\nAgain, any thoughts of this or pointers to texts that discuss these\nissues would be appreciated.\n\n--\nMike Helland\nhttp://www.techmocracy.net/science/time.htm\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>In the two main theories of physics (relativity and quantum) the role
of observers or observations seems to be pretty important.

Is there text available that rigourously defines these concepts?

Specifically I would like to know if the established thinking is that
only a human being may observe. This seems to be a common belief I
see. Is this supported by any hypothesis or literature?

If nature is viewed as an evolving system wherein agents are involved
in interactions, what role in this system does "observer" or
"observation" play that is not adequately fulfilled by "agent" or
"interaction"?

It seems to me that "observation" only describes a level of
sophistication involved in the interaction. For example, consider
particles in a tree interacting with particles in my eye. This
interaction occurs even if I'm lieing on the ground dead. The
difference is that when I'm dead my nerves and brain do not react the
same way as when I'm alive.

These actions by my nerves and brain are really nothing more than
several additional levels of the same types of interactions in a
complex network. The interactions of a living human being are more
sophisticated than other interactions by non humans, and I think this
is why we call our sophisticated interactions "observations."

I think the important question is then:

Is this sophistication really relevent in our formulating of physical
theories about the fundamentals of the universe?

Again, any thoughts of this or pointers to texts that discuss these
issues would be appreciated.

--
Mike Helland
http://www.techmocracy.net/science/time.htm

Harry

Jun16-04, 06:18 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n"Mike Helland" <mhelland@techmocracy.net> wrote in message\nnews:ad157aec.0406150734.5f9546a7@posting .google.com...\n>\n> In the two main theories of physics (relativity and quantum) the role\n> of observers or observations seems to be pretty important.\n\nThat is so because it is essentially the only scientific certainty we have,\nsee below.\n\n> Is there text available that rigourously defines these concepts?\n>\n> Specifically I would like to know if the established thinking is that\n> only a human being may observe. This seems to be a common belief I\n> see. Is this supported by any hypothesis or literature?\n\nNot so. Any sensor or measurement instrument can play the role of an\n"observer". In many physics experiments no direct human observer is present.\n\nHarald\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Mike Helland" <mhelland@techmocracy.net> wrote in message
news:ad157aec.0406150734.5f9546a7@posting.google.c om...
>
> In the two main theories of physics (relativity and quantum) the role
> of observers or observations seems to be pretty important.

That is so because it is essentially the only scientific certainty we have,
see below.

> Is there text available that rigourously defines these concepts?
>
> Specifically I would like to know if the established thinking is that
> only a human being may observe. This seems to be a common belief I
> see. Is this supported by any hypothesis or literature?

Not so. Any sensor or measurement instrument can play the role of an
"observer". In many physics experiments no direct human observer is present.

Harald

Arkadiusz Jadczyk

Jun16-04, 11:35 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\nOn 16 Jun 2004 04:56:13 -0400, mhelland@techmocracy.net (Mike Helland)\nwrote:\n\n>Is this sophistication really relevent in our formulating of physical\n>theories about the fundamentals of the universe?\n\nThe question goes deeper, or so I think.\n\nThere is something more fundamental than "observation", and this\nsomething is better hidden from our scrutiny.\n\nThe deeper question is: Does anything ever "happen"?\n\nYou write "For example, consider\nparticles in a tree interacting with particles in my eye."\n\nYou are using the term "occurs". You believe that something "occurs"\neven when you are dead. But how do you know? Suppose everybody is dead.\nWhat would it MEAN that "interaction occurs?\'\n\nThere is a problem here. But only some people see a problem here. Most\npeople will not see a problem. Or even if the see, they dismiss it.\n\nJohn Bell wrote: " .. the term `measurement\' should be banned from any\nserious discussion..." So he understood that there is a problem.\n\nHe was seeking a solution to this problem, and could not find anything\nbetter than GRW theory with a spontaneous collapse.\n\nIt is possible to generalize GRW formalism, so that it can be applied\nto more general experimental situations than just collapse in x-space.\n\nA discussion of this aspect can be found in:\n\n"Event-Enhanced Quantum Theory And Piecewise Deterministic Dynamics"\n\nhttp://xxx.lanl.gov/abs/hep-th/9409189\n\n\nark\n--\n\nArkadiusz Jadczyk\nhttp://www.cassiopaea.org/quantum_future/homepage.htm\n\n--\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>On 16 Jun 2004 04:56:13 -0400, mhelland@techmocracy.net (Mike Helland)
wrote:

>Is this sophistication really relevent in our formulating of physical
>theories about the fundamentals of the universe?

The question goes deeper, or so I think.

There is something more fundamental than "observation", and this
something is better hidden from our scrutiny.

The deeper question is: Does anything ever "happen"?

You write "For example, consider
particles in a tree interacting with particles in my eye."

You are using the term "occurs". You believe that something "occurs"
even when you are dead. But how do you know? Suppose everybody is dead.
What would it MEAN that "interaction occurs?'

There is a problem here. But only some people see a problem here. Most
people will not see a problem. Or even if the see, they dismiss it.

John Bell wrote: " .. the term `measurement' should be banned from any
serious discussion..." So he understood that there is a problem.

He was seeking a solution to this problem, and could not find anything
better than GRW theory with a spontaneous collapse.

It is possible to generalize GRW formalism, so that it can be applied
to more general experimental situations than just collapse in x-space.

A discussion of this aspect can be found in:

"Event-Enhanced Quantum Theory And Piecewise Deterministic Dynamics"

http://xxx.lanl.gov/abs/http://www.arxiv.org/abs/hep-th/9409189

ark
--

Arkadiusz Jadczyk
http://www.cassiopaea.org/quantum_future/homepage.htm

--

Mike Helland

Jun17-04, 04:19 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n\n"Harry" <harald.vanlintel@epfl.ch> wrote in message news:<40d02b22\\$1@epflnews.epfl.ch>...\n> "Mike Helland" <mhelland@techmocracy.net> wrote in message\n> news:ad157aec.0406150734.5f9546a7@posting.google.c om...\n\nThanks for the response.\n\n<snip>\n\n> > Is there text available that rigourously defines these concepts?\n> >\n> > Specifically I would like to know if the established thinking is that\n> > only a human being may observe. This seems to be a common belief I\n> > see. Is this supported by any hypothesis or literature?\n>\n> Not so. Any sensor or measurement instrument can play the role of an\n> "observer". In many physics experiments no direct human observer is present.\n\nWhat I\'m interested in is what is the simplest mechanism that we may\ndescribe as an observer. A single molecule, atom, or even particle?\n\nTo get closer to the heart of the matter, I\'ll rephrase a question\nfrom my first post:\n\nIf nature is viewed as a system of interacting bodies can we say that\nany body may be an "observer" and that any interaction may be an\n"observation"?\n\nThis appears to be an acceptable claim to me.\n\n--\nMike Helland\nhttp://www.techmocracy.net/science/time.htm\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Harry" <harald.vanlintel@epfl.ch> wrote in message news:<40d02b22$1@epflnews.epfl.ch>...
> "Mike Helland" <mhelland@techmocracy.net> wrote in message
> news:ad157aec.0406150734.5f9546a7@posting.google.c om...

Thanks for the response.

<snip>

> > Is there text available that rigourously defines these concepts?
> >
> > Specifically I would like to know if the established thinking is that
> > only a human being may observe. This seems to be a common belief I
> > see. Is this supported by any hypothesis or literature?
>
> Not so. Any sensor or measurement instrument can play the role of an
> "observer". In many physics experiments no direct human observer is present.

What I'm interested in is what is the simplest mechanism that we may
describe as an observer. A single molecule, atom, or even particle?

To get closer to the heart of the matter, I'll rephrase a question
from my first post:

If nature is viewed as a system of interacting bodies can we say that
any body may be an "observer" and that any interaction may be an
"observation"?

This appears to be an acceptable claim to me.

--
Mike Helland
http://www.techmocracy.net/science/time.htm

Arnold Neumaier

Jun17-04, 05:38 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\nMike Helland wrote:\n> In the two main theories of physics (relativity and quantum) the role\n> of observers or observations seems to be pretty important.\n>\n> Is there text available that rigourously defines these concepts?\n\nPerhaps the best book about foundations of QM is the one by Asher Peres.\n\nBut I think nowhere rigorous definitions are given. People disagree\n(or don\'t care) about what their concepts \'really\' mean on a formal level,\nsince once you get precise, one can do nothing with the result.\n\n\nArnold Neumaier\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Mike Helland wrote:
> In the two main theories of physics (relativity and quantum) the role
> of observers or observations seems to be pretty important.
>
> Is there text available that rigourously defines these concepts?

Perhaps the best book about foundations of QM is the one by Asher Peres.

But I think nowhere rigorous definitions are given. People disagree
(or don't care) about what their concepts 'really' mean on a formal level,
since once you get precise, one can do nothing with the result.

Arnold Neumaier

Vincent N. Virgilio

Jun17-04, 04:09 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>Mike Helland wrote:\n\n> In the two main theories of physics (relativity and quantum) the role\n> of observers or observations seems to be pretty important.\n>\n> Is there text available that rigourously defines these concepts?\n>\n> Specifically I would like to know if the established thinking is that\n> only a human being may observe. This seems to be a common belief I\n> see. Is this supported by any hypothesis or literature?\n>\n> If nature is viewed as an evolving system wherein agents are involved\n> in interactions, what role in this system does "observer" or\n> "observation" play that is not adequately fulfilled by "agent" or\n> "interaction"?\n>\n> It seems to me that "observation" only describes a level of\n> sophistication involved in the interaction. For example, consider\n> particles in a tree interacting with particles in my eye. This\n> interaction occurs even if I\'m lieing on the ground dead. The\n> difference is that when I\'m dead my nerves and brain do not react the\n> same way as when I\'m alive.\n>\n> These actions by my nerves and brain are really nothing more than\n> several additional levels of the same types of interactions in a\n> complex network. The interactions of a living human being are more\n> sophisticated than other interactions by non humans, and I think this\n> is why we call our sophisticated interactions "observations."\n>\n> I think the important question is then:\n>\n> Is this sophistication really relevent in our formulating of physical\n> theories about the fundamentals of the universe?\n>\n> Again, any thoughts of this or pointers to texts that discuss these\n> issues would be appreciated.\n>\n> --\n> Mike Helland\n> http://www.techmocracy.net/science/time.htm\n\nHi Mike,\n\nI just stumbled across something in my reading [1] that I think is\nrelevant. It\'s an excerpt called "Schrodinger\'s Cat" by Heinz R. Pagels.\nPagels says that the important feature of an observation is that we\nobtain information about it, which is not possible without increasing\nentropy.\n\nHe ends like this:\n\n"Irreversibility in time is the principal feature of observation, not\nconsciousness of the observation, although that, of course, also entails\nirreversibility because it involves memory. Observations can be carried\nout by dumb machines or computers [or a cat?], provided they have some\nprimitive memory storage. The main point in this analysis of observation\nis that once information about the quantum world is irreversibly in the\nmacroscopic world, we can safely attribute objective significance to it\n-- it can\'t slip back into the quantum never-never land . . ."\n\nSo, a falling tree sounds like an entropy-ridden thing to me, which\nleads me to believe in the fall; even if I wasn\'t there.\n\nI wonder if this is a vulgar statement of the \'decoherence\' concept\nfound elsewhere on this list.\n\nRegards,\n\nVince Virgilio\n\n[1] Ferris, Timothy (ed), "The World Treasury of Physics, Astronomy, and\nMathematics", Little, Brown, 1991\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Mike Helland wrote:

> In the two main theories of physics (relativity and quantum) the role
> of observers or observations seems to be pretty important.
>
> Is there text available that rigourously defines these concepts?
>
> Specifically I would like to know if the established thinking is that
> only a human being may observe. This seems to be a common belief I
> see. Is this supported by any hypothesis or literature?
>
> If nature is viewed as an evolving system wherein agents are involved
> in interactions, what role in this system does "observer" or
> "observation" play that is not adequately fulfilled by "agent" or
> "interaction"?
>
> It seems to me that "observation" only describes a level of
> sophistication involved in the interaction. For example, consider
> particles in a tree interacting with particles in my eye. This
> interaction occurs even if I'm lieing on the ground dead. The
> difference is that when I'm dead my nerves and brain do not react the
> same way as when I'm alive.
>
> These actions by my nerves and brain are really nothing more than
> several additional levels of the same types of interactions in a
> complex network. The interactions of a living human being are more
> sophisticated than other interactions by non humans, and I think this
> is why we call our sophisticated interactions "observations."
>
> I think the important question is then:
>
> Is this sophistication really relevent in our formulating of physical
> theories about the fundamentals of the universe?
>
> Again, any thoughts of this or pointers to texts that discuss these
> issues would be appreciated.
>
> --
> Mike Helland
> http://www.techmocracy.net/science/time.htm

Hi Mike,

I just stumbled across something in my reading [1] that I think is
relevant. It's an excerpt called "Schrodinger's Cat" by Heinz R. Pagels.
Pagels says that the important feature of an observation is that we
obtain information about it, which is not possible without increasing
entropy.

He ends like this:

"Irreversibility in time is the principal feature of observation, not
consciousness of the observation, although that, of course, also entails
irreversibility because it involves memory. Observations can be carried
out by dumb machines or computers [or a cat?], provided they have some
primitive memory storage. The main point in this analysis of observation
is that once information about the quantum world is irreversibly in the
macroscopic world, we can safely attribute objective significance to it
-- it can't slip back into the quantum never-never land . . ."

So, a falling tree sounds like an entropy-ridden thing to me, which
leads me to believe in the fall; even if I wasn't there.

I wonder if this is a vulgar statement of the 'decoherence' concept
found elsewhere on this list.

Regards,

Vince Virgilio

[1] Ferris, Timothy (ed), "The World Treasury of Physics, Astronomy, and
Mathematics", Little, Brown, 1991

Frank Hellmann

Jun17-04, 04:11 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>mhelland@techmocracy.net (Mike Helland) wrote in message news:<ad157aec.0406162108.289c1c6a@posting.google. com>...\n> "Harry" <harald.vanlintel@epfl.ch> wrote in message news:<40d02b22\\$1@epflnews.epfl.ch>...\n> > "Mike Helland" <mhelland@techmocracy.net> wrote in message\n> > news:ad157aec.0406150734.5f9546a7@posting.google.c om...\n>\n> Thanks for the response.\n>\n> <snip>\n>\n> > > Is there text available that rigourously defines these concepts?\n> > >\n> > > Specifically I would like to know if the established thinking is that\n> > > only a human being may observe. This seems to be a common belief I\n> > > see. Is this supported by any hypothesis or literature?\n> >\n> > Not so. Any sensor or measurement instrument can play the role of an\n> > "observer". In many physics experiments no direct human observer is present.\n>\n> What I\'m interested in is what is the simplest mechanism that we may\n> describe as an observer. A single molecule, atom, or even particle?\n>\n> To get closer to the heart of the matter, I\'ll rephrase a question\n> from my first post:\n>\n> If nature is viewed as a system of interacting bodies can we say that\n> any body may be an "observer" and that any interaction may be an\n> "observation"?\n>\n> This appears to be an acceptable claim to me.\n\n\nAd hoc I would say irreversible interaction where the final state of a\nlarger system critically depends on the intial state of a smaller\nsystem.\n\nThis is of course not any precise either, but IMHO this is because to\nask whether something is an observation is like asking whether\nsomething is fast. It\'s context sensitive.\nIt\'s not completely relative because we have lightspeed as max. So we\ncould ask when is it so fast that we get new (phenomenological)\nphysics?\nHow much do we have to interact to get a meassurement then? In QM\nthat\'s a question related to decoherence, but finally unanwserable\nsine we haven\'t figured out what a meassurement in QM is, we need to\npostulate it.\nIn classical mechanics it\'s related to nonequillibrium statistical\nmechanics and chaos, and thus not really well understood either.\n\n---\nfrank\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>mhelland@techmocracy.net (Mike Helland) wrote in message news:<ad157aec.0406162108.289c1c6a@posting.google.com>...
> "Harry" <harald.vanlintel@epfl.ch> wrote in message news:<40d02b22$1@epflnews.epfl.ch>...
> > "Mike Helland" <mhelland@techmocracy.net> wrote in message
> > news:ad157aec.0406150734.5f9546a7@posting.google.c om...
>
> Thanks for the response.
>
> <snip>
>
> > > Is there text available that rigourously defines these concepts?
> > >
> > > Specifically I would like to know if the established thinking is that
> > > only a human being may observe. This seems to be a common belief I
> > > see. Is this supported by any hypothesis or literature?
> >
> > Not so. Any sensor or measurement instrument can play the role of an
> > "observer". In many physics experiments no direct human observer is present.
>
> What I'm interested in is what is the simplest mechanism that we may
> describe as an observer. A single molecule, atom, or even particle?
>
> To get closer to the heart of the matter, I'll rephrase a question
> from my first post:
>
> If nature is viewed as a system of interacting bodies can we say that
> any body may be an "observer" and that any interaction may be an
> "observation"?
>
> This appears to be an acceptable claim to me.

Ad hoc I would say irreversible interaction where the final state of a
larger system critically depends on the intial state of a smaller
system.

This is of course not any precise either, but IMHO this is because to
ask whether something is an observation is like asking whether
something is fast. It's context sensitive.
It's not completely relative because we have lightspeed as max. So we
could ask when is it so fast that we get new (phenomenological)
physics?
How much do we have to interact to get a meassurement then? In QM
that's a question related to decoherence, but finally unanwserable
sine we haven't figured out what a meassurement in QM is, we need to
postulate it.
In classical mechanics it's related to nonequillibrium statistical
mechanics and chaos, and thus not really well understood either.

---
frank

Ralph E. Frost

Jun17-04, 06:14 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>"Harry" <harald.vanlintel@epfl.ch> wrote in message\nnews:40d02b22\\$1@epflnews.epfl.ch...\n>\ n> "Mike Helland" <mhelland@techmocracy.net> wrote in message\n> news:ad157aec.0406150734.5f9546a7@posting.google.c om...\n> >\n> > In the two main theories of physics (relativity and quantum) the role\n> > of observers or observations seems to be pretty important.\n>\n> That is so because it is essentially the only scientific certainty we\nhave,\n> see below.\n>\n> > Is there text available that rigourously defines these concepts?\n> >\n> > Specifically I would like to know if the established thinking is that\n> > only a human being may observe. This seems to be a common belief I\n> > see. Is this supported by any hypothesis or literature?\n>\n> Not so. Any sensor or measurement instrument can play the role of an\n> "observer". In many physics experiments no direct human observer is\npresent.\n\nI\'m intrigued by this statement since I keep thinking some human\nparticipation is involved in the setup, conduct, take-down or interpretation\nof 100% of all physics experiments. Otherwise, they are like trees falling\nsoundlessly in the forest.\n\nAre you referring to the data collection phase? Can you give examples of\nthe types of things you are thinking about?\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Harry" <harald.vanlintel@epfl.ch> wrote in message
news:40d02b22$1@epflnews.epfl.ch...
>
> "Mike Helland" <mhelland@techmocracy.net> wrote in message
> news:ad157aec.0406150734.5f9546a7@posting.google.c om...
> >
> > In the two main theories of physics (relativity and quantum) the role
> > of observers or observations seems to be pretty important.
>
> That is so because it is essentially the only scientific certainty we
have,
> see below.
>
> > Is there text available that rigourously defines these concepts?
> >
> > Specifically I would like to know if the established thinking is that
> > only a human being may observe. This seems to be a common belief I
> > see. Is this supported by any hypothesis or literature?
>
> Not so. Any sensor or measurement instrument can play the role of an
> "observer". In many physics experiments no direct human observer is
present.

I'm intrigued by this statement since I keep thinking some human
participation is involved in the setup, conduct, take-down or interpretation
of 100% of all physics experiments. Otherwise, they are like trees falling
soundlessly in the forest.

Are you referring to the data collection phase? Can you give examples of
the types of things you are thinking about?

Mike Helland

Jun17-04, 06:14 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>"Harry" <harald.vanlintel@epfl.ch> wrote in message news:<40d02b22\\$1@epflnews.epfl.ch>...\n> "Mike Helland" <mhelland@techmocracy.net> wrote in message\n> news:ad157aec.0406150734.5f9546a7@posting.google.c om...\n\nThanks for the response.\n\n<snip>\n\n> > Is there text available that rigourously defines these concepts?\n> >\n> > Specifically I would like to know if the established thinking is that\n> > only a human being may observe. This seems to be a common belief I\n> > see. Is this supported by any hypothesis or literature?\n>\n> Not so. Any sensor or measurement instrument can play the role of an\n> "observer". In many physics experiments no direct human observer is present.\n\nWhat I\'m interested in is what is the simplest mechanism that we may\ndescribe as an observer. A single molecule, atom, or even particle?\n\nTo get closer to the heart of the matter, I\'ll rephrase a question\nfrom my first post:\n\nIf nature is viewed as a system of interacting bodies can we say that\nany body may be an "observer" and that any interaction may be an\n"observation"?\n\nThis appears to be an acceptable claim to me.\n\n--\nMike Helland\nhttp://www.techmocracy.net/science/time.htm\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Harry" <harald.vanlintel@epfl.ch> wrote in message news:<40d02b22$1@epflnews.epfl.ch>...
> "Mike Helland" <mhelland@techmocracy.net> wrote in message
> news:ad157aec.0406150734.5f9546a7@posting.google.c om...

Thanks for the response.

<snip>

> > Is there text available that rigourously defines these concepts?
> >
> > Specifically I would like to know if the established thinking is that
> > only a human being may observe. This seems to be a common belief I
> > see. Is this supported by any hypothesis or literature?
>
> Not so. Any sensor or measurement instrument can play the role of an
> "observer". In many physics experiments no direct human observer is present.

What I'm interested in is what is the simplest mechanism that we may
describe as an observer. A single molecule, atom, or even particle?

To get closer to the heart of the matter, I'll rephrase a question
from my first post:

If nature is viewed as a system of interacting bodies can we say that
any body may be an "observer" and that any interaction may be an
"observation"?

This appears to be an acceptable claim to me.

--
Mike Helland
http://www.techmocracy.net/science/time.htm

Arnold Neumaier

Jun17-04, 06:15 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>Mike Helland wrote:\n\n>>>Specifically I would like to know if the established thinking is that\n>>>only a human being may observe. This seems to be a common belief I\n>>>see. Is this supported by any hypothesis or literature?\n>>\n>>Not so. Any sensor or measurement instrument can play the role of an\n>>"observer". In many physics experiments no direct human observer is present.\n>\n>\n> What I\'m interested in is what is the simplest mechanism that we may\n> describe as an observer. A single molecule, atom, or even particle?\n>\n> To get closer to the heart of the matter, I\'ll rephrase a question\n> from my first post:\n>\n> If nature is viewed as a system of interacting bodies can we say that\n> any body may be an "observer" and that any interaction may be an\n> "observation"?\n\nNo. Observation is a thermodynamic phenomemon requiring dissipation\nand reasonable permanence of the record.\n\nThus an observer must be a macroscopic object with some slowly varying\nmodes to hold the record. How large depends on the quality of the\nmeasurement. An ideal (von Neumann) measurement requires an infinitely\nlarge object (thermodynamic limit).\n\n\nArnold Neumaier\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Mike Helland wrote:

>>>Specifically I would like to know if the established thinking is that
>>>only a human being may observe. This seems to be a common belief I
>>>see. Is this supported by any hypothesis or literature?
>>
>>Not so. Any sensor or measurement instrument can play the role of an
>>"observer". In many physics experiments no direct human observer is present.
>
>
> What I'm interested in is what is the simplest mechanism that we may
> describe as an observer. A single molecule, atom, or even particle?
>
> To get closer to the heart of the matter, I'll rephrase a question
> from my first post:
>
> If nature is viewed as a system of interacting bodies can we say that
> any body may be an "observer" and that any interaction may be an
> "observation"?

No. Observation is a thermodynamic phenomemon requiring dissipation
and reasonable permanence of the record.

Thus an observer must be a macroscopic object with some slowly varying
modes to hold the record. How large depends on the quality of the
measurement. An ideal (von Neumann) measurement requires an infinitely
large object (thermodynamic limit).

Arnold Neumaier

Ralph E. Frost

Jun17-04, 06:15 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>"Mike Helland" <mhelland@techmocracy.net> wrote in message\nnews:ad157aec.0406162108.289c1c6a@posting .google.com...\n>\n>\n> "Harry" <harald.vanlintel@epfl.ch> wrote in message\nnews:<40d02b22\\$1@epflnews.epfl.ch>...\n > > "Mike Helland" <mhelland@techmocracy.net> wrote in message\n> > news:ad157aec.0406150734.5f9546a7@posting.google.c om...\n>\n> Thanks for the response.\n>\n> <snip>\n>\n> > > Is there text available that rigourously defines these concepts?\n> > >\n> > > Specifically I would like to know if the established thinking is that\n> > > only a human being may observe. This seems to be a common belief I\n> > > see. Is this supported by any hypothesis or literature?\n> >\n> > Not so. Any sensor or measurement instrument can play the role of an\n> > "observer". In many physics experiments no direct human observer is\npresent.\n>\n> What I\'m interested in is what is the simplest mechanism that we may\n> describe as an observer. A single molecule, atom, or even particle?\n>\n> To get closer to the heart of the matter, I\'ll rephrase a question\n> from my first post:\n>\n> If nature is viewed as a system of interacting bodies can we say that\n> any body may be an "observer" and that any interaction may be an\n> "observation"?\n>\n> This appears to be an acceptable claim to me.\n\nMight it be better to scrap the idealized notion of "an observer and refer\nto participants? Perhaps qualifying futher to participants who can or do\nreport?\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Mike Helland" <mhelland@techmocracy.net> wrote in message
news:ad157aec.0406162108.289c1c6a@posting.google.c om...
>
>
> "Harry" <harald.vanlintel@epfl.ch> wrote in message
news:<40d02b22$1@epflnews.epfl.ch>...
> > "Mike Helland" <mhelland@techmocracy.net> wrote in message
> > news:ad157aec.0406150734.5f9546a7@posting.google.c om...
>
> Thanks for the response.
>
> <snip>
>
> > > Is there text available that rigourously defines these concepts?
> > >
> > > Specifically I would like to know if the established thinking is that
> > > only a human being may observe. This seems to be a common belief I
> > > see. Is this supported by any hypothesis or literature?
> >
> > Not so. Any sensor or measurement instrument can play the role of an
> > "observer". In many physics experiments no direct human observer is
present.
>
> What I'm interested in is what is the simplest mechanism that we may
> describe as an observer. A single molecule, atom, or even particle?
>
> To get closer to the heart of the matter, I'll rephrase a question
> from my first post:
>
> If nature is viewed as a system of interacting bodies can we say that
> any body may be an "observer" and that any interaction may be an
> "observation"?
>
> This appears to be an acceptable claim to me.

Might it be better to scrap the idealized notion of "an observer and refer
to participants? Perhaps qualifying futher to participants who can or do
report?

Harry

Jun18-04, 01:26 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n"Ralph E. Frost" <ralph@REMOVErefrost.com> wrote in message\nnews:10d0fdc42p3f24d@corp.supernews.com.. .\n> "Harry" <harald.vanlintel@epfl.ch> wrote in message\n> news:40d02b22\\$1@epflnews.epfl.ch...\n> >\n> > "Mike Helland" <mhelland@techmocracy.net> wrote in message\n> > news:ad157aec.0406150734.5f9546a7@posting.google.c om...\n> > >\n> > > In the two main theories of physics (relativity and quantum) the role\n> > > of observers or observations seems to be pretty important.\n> >\n> > That is so because it is essentially the only scientific certainty we\n> have,\n> > see below.\n> >\n> > > Is there text available that rigourously defines these concepts?\n> > >\n> > > Specifically I would like to know if the established thinking is that\n> > > only a human being may observe. This seems to be a common belief I\n> > > see. Is this supported by any hypothesis or literature?\n> >\n> > Not so. Any sensor or measurement instrument can play the role of an\n> > "observer". In many physics experiments no direct human observer is\n> present.\n>\n> I\'m intrigued by this statement since I keep thinking some human\n> participation is involved in the setup, conduct, take-down or\ninterpretation\n> of 100% of all physics experiments. Otherwise, they are like trees\nfalling\n> soundlessly in the forest.\n>\n> Are you referring to the data collection phase? Can you give examples of\n> the types of things you are thinking about?\n\nYes with "direct" I meant the data collection, such as for example a\ntemperature sensor or a CCD camera that sends data to a computer.\nI know that there are claims that that data can be influenced by the thought\nprocesses of living species (Princeton PEAR), but I\'m not convinced as there\nhave been no completely independent confirmation to my knowledge.\n\n\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Ralph E. Frost" <ralph@REMOVErefrost.com> wrote in message
news:10d0fdc42p3f24d@corp.supernews.com...
> "Harry" <harald.vanlintel@epfl.ch> wrote in message
> news:40d02b22$1@epflnews.epfl.ch...
> >
> > "Mike Helland" <mhelland@techmocracy.net> wrote in message
> > news:ad157aec.0406150734.5f9546a7@posting.google.c om...
> > >
> > > In the two main theories of physics (relativity and quantum) the role
> > > of observers or observations seems to be pretty important.
> >
> > That is so because it is essentially the only scientific certainty we
> have,
> > see below.
> >
> > > Is there text available that rigourously defines these concepts?
> > >
> > > Specifically I would like to know if the established thinking is that
> > > only a human being may observe. This seems to be a common belief I
> > > see. Is this supported by any hypothesis or literature?
> >
> > Not so. Any sensor or measurement instrument can play the role of an
> > "observer". In many physics experiments no direct human observer is
> present.
>
> I'm intrigued by this statement since I keep thinking some human
> participation is involved in the setup, conduct, take-down or
interpretation
> of 100% of all physics experiments. Otherwise, they are like trees
falling
> soundlessly in the forest.
>
> Are you referring to the data collection phase? Can you give examples of
> the types of things you are thinking about?

Yes with "direct" I meant the data collection, such as for example a
temperature sensor or a CCD camera that sends data to a computer.
I know that there are claims that that data can be influenced by the thought
processes of living species (Princeton PEAR), but I'm not convinced as there
have been no completely independent confirmation to my knowledge.

tessel@tum.bot

Jun22-04, 03:13 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>On Wed, 16 Jun 2004, Mike Helland wrote:\n\n> In the two main theories of physics (relativity and quantum) the role\n> of observers or observations seems to be pretty important.\n>\n> Is there text available that rigourously defines these concepts?\n\nWrt the notion of "observer" in QM, probably others will help you with\nthis; if not, you can look for previous posts here by John Baez discussing\nthis topic (see also the collected "This Weeks" on his web pages).\n\nWrt the notion of "observer" mentioned in papers dealing with classical\nrelativistic gravitation theories such as gtr: I presume you have some\nidea how this term is used -informally-. The classical usage is less\nproblematic than the QM usage, but still philosophically and sometimes\neven technically challenging.\n\nMore generally, not many textbooks discuss -measurements- (made by\n"observers") in classical spacetimes. One of the few which does is\n\ntitle = {Relativity on Curved Manifolds},\npublisher = {Cambridge University Press},\nyear = 1990}\n\nYou may also be interested in a brief discussion of an (informal) attempt\n"axiomatization" of gtr in\n\nauthor = {S. W. Hawking and G. F. R. Ellis},\ntitle = {The Large Scale Structure of Space-Time},\npublisher = {Cambridge University Press},\nyear = 1973}\n\n"T. Essel" (hiding somewhere in cyberspace)\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>On Wed, 16 Jun 2004, Mike Helland wrote:

> In the two main theories of physics (relativity and quantum) the role
> of observers or observations seems to be pretty important.
>
> Is there text available that rigourously defines these concepts?

Wrt the notion of "observer" in QM, probably others will help you with
this; if not, you can look for previous posts here by John Baez discussing
this topic (see also the collected "This Weeks" on his web pages).

Wrt the notion of "observer" mentioned in papers dealing with classical
relativistic gravitation theories such as gtr: I presume you have some
idea how this term is used -informally-. The classical usage is less
problematic than the QM usage, but still philosophically and sometimes
even technically challenging.

More generally, not many textbooks discuss -measurements- (made by
"observers") in classical spacetimes. One of the few which does is

title = {Relativity on Curved Manifolds},
publisher = {Cambridge University Press},
year = 1990}

You may also be interested in a brief discussion of an (informal) attempt
"axiomatization" of gtr in

author = {S. W. Hawking and G. F. R. Ellis},
title = {The Large Scale Structure of Space-Time},
publisher = {Cambridge University Press},
year = 1973}

"T. Essel" (hiding somewhere in cyberspace)

mandro

Jun22-04, 03:13 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\nMike Helland wrote:\n\n>What I\'m interested in is what is the simplest mechanism\n>that we may describe as an observer. A single molecule, >atom, or even >particle?\n\n\nIn my view, you\'re almost on the right track. I suspect\nthough that ultimately the question of what\'s an observer\n(I mean observer in some platonic sense) may not be\nimportant or even sensical. Then you\'d want a more\nprecise object to replace "observer". now, seeing how\nyou yourself have noticed that a human observer is not\nthe only thing that one can mean by observer, how\'s\nabout this: Ultimately, again you seemed to have noticed\nthis, an observer may be any physical system. Now based\non how this system behaves (i.e., how it looks before and\nafter an interaction) determines the "character" of the\nobservation. Also notice that the complexity of the\nobserver determines the kind of observations that it can\nand cannot make. E.g., if you have an "eye" that has no\nspatial extent, then you may not be able to see angles\nin fact all you\'ll be able to see are points. I mean\nultimately, in most modern theories of physics, observers,\nwhether a human being or a detector, are collections\nof particles (with the possibility of splitting into\nmore particle--i.e., particle creation and annihilation)\nand, what determines if (and how) an observation was made\nis a whole history of the system of particles (Here I\ndeeply suspect that to describe the whole observation I\nneed to include the particles being observed. In other\nwords, you set up a physical model of the observer and\nthe observed as a system of particles, you set up an\ninitial configuration, and then you evolve the system in\ntime and see what develops (I.e., a history of the physical\nsystem) Then, depending on how the observer behaved, you\nsay: "He detected the particle", or "He didn\'t detect the\nparticle". of course, there\'s much more information here\nthan this, because this also contains information on\n"how he detected the particle" I.e., it contains the\ndefinition particular to this particular "observer" for\nwhat it means for it to "detect the particle".\n\n>To get closer to the heart of the matter, I\'ll rephrase\n>a question from my first post:\n>If nature is viewed as a system of interacting bodies can\n>we say that any body may be an "observer" and that any\n>interaction may be an "observation"?\n\n\nYes, almost. But it almost seems like -> V.S.\n<-> . I.e., every observation can be described by\nan interaction, but not every interaction is an\nobservation--at least I\'d say. However, if your\nmain point is that the meaningful, more general\nidea of what an observation is is that it\'s an\ninteraction, I particularly, agree with you.\nOf course the neat thing would be to describe\nmany observation processes with different "model\nobservers" so that one can get more insight into\nthese ideas.\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Mike Helland wrote:

>What I'm interested in is what is the simplest mechanism
>that we may describe as an observer. A single molecule, >atom, or even >particle?

In my view, you're almost on the right track. I suspect
though that ultimately the question of what's an observer
(I mean observer in some platonic sense) may not be
important or even sensical. Then you'd want a more
precise object to replace "observer". now, seeing how
you yourself have noticed that a human observer is not
the only thing that one can mean by observer, how's
about this: Ultimately, again you seemed to have noticed
this, an observer may be any physical system. Now based
on how this system behaves (i.e., how it looks before and
after an interaction) determines the "character" of the
observation. Also notice that the complexity of the
observer determines the kind of observations that it can
and cannot make. E.g., if you have an "eye" that has no
spatial extent, then you may not be able to see angles
in fact all you'll be able to see are points. I mean
ultimately, in most modern theories of physics, observers,
whether a human being or a detector, are collections
of particles (with the possibility of splitting into
more particle--i.e., particle creation and annihilation)
and, what determines if (and how) an observation was made
is a whole history of the system of particles (Here I
deeply suspect that to describe the whole observation I
need to include the particles being observed. In other
words, you set up a physical model of the observer and
the observed as a system of particles, you set up an
initial configuration, and then you evolve the system in
time and see what develops (I.e., a history of the physical
system) Then, depending on how the observer behaved, you
say: "He detected the particle", or "He didn't detect the
particle". of course, there's much more information here
than this, because this also contains information on
"how he detected the particle" I.e., it contains the
definition particular to this particular "observer" for
what it means for it to "detect the particle".

>To get closer to the heart of the matter, I'll rephrase
>a question from my first post:
>If nature is viewed as a system of interacting bodies can
>we say that any body may be an "observer" and that any
>interaction may be an "observation"?

Yes, almost. But it almost seems like -> V.S.
<-> . I.e., every observation can be described by
an interaction, but not every interaction is an
observation--at least I'd say. However, if your
main point is that the meaningful, more general
idea of what an observation is is that it's an
interaction, I particularly, agree with you.
Of course the neat thing would be to describe
many observation processes with different "model
observers" so that one can get more insight into
these ideas.

Thomas Larsson

Jun22-04, 06:02 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\nMike Helland <mhelland@techmocracy.net> skrev i\ndiskussionsgruppsmeddelandet:ad157aec.040615073 4.5f9546a7@posting.google.com...\n>\n> In the two main theories of physics (relativity and quantum) the role\n> of observers or observations seems to be pretty important.\n\nUsually I try to avoid thorny interpretational issues, and rather\nfollow\nFeynman\'s dictum - shut up and calculate. However, understanding the\nnotion of an observer is an exception, since IMO (but in nobody\nelse\'s)\nthis holds the key to quantum gravity.\n\n>\n> Is there text available that rigourously defines these concepts?\n>\n> Specifically I would like to know if the established thinking is that\n> only a human being may observe.\n\nIMO, the important thing is not *what* the observer is, but *where*\nshe\nis. Assuming that the observer is small, she will move around in\nspacetime along some timelike curve q(t), presumably a geodesic. The\nreason why I think that this is important is the existence of diff\nanomalies which are functionals of q(t).\n\n(A diff anomaly is a breakdown of diffeomorphism symmetry, pertinent\nto\ngeneral relativity. Technically, this is an extension of the\ndiffeomorphism algebra, i.e. a generalization of the Virasoro algebra\nto\nseveral dimensions.)\n\nNow, it is well known that within field theory, there are no diff\nanomalies in 4D. This is natural because field theory does not\nexplicitly involve the observer\'s trajectory, so there is no way to\nformulate these anomalies. Of course, this is the point where\neverybody\nautomatically puts up their noses in the air, say "gauge anomaly" and\nshut their ears. Perhaps justly so, but the fact that diff anomalies\nexist in 4D if one is willing to slightly relax the field theory\nparadigm is rather striking, and indicates perhaps that there is more\nto\nanomalies than meets the eye.\n\nThere is a philosophical problem with specifying a quantum field\nthroughout spacetime. By doing so, we in some sense assume the role of\na\ndivine observer who has access to the whole of spacetime, including\nevents that are separated by spacelike distances. But an observer can\nonly detect events on her worldline. One way to model this is to\nexpand\nall fields in a Taylor series around q(t) (written in 1D for\nsimplicity),\n\nf(x) = sum_m f_m(t) (x-q(t))^m .\n\n(The Taylor coefficients f_m(t) must satisfy some additional\nconditions\nto make f(x) independent of t). Classically at least, physics can be\nformulated in terms of Taylor data { q(t), f_m(t) }, rather than the\nfield data f(x), although this may be awkward in practice and may lead\nto convergence problems. Such a formulation allows anomalies depending\non q(t) to arise.\n\nTo summarize, my position is that because of the unity of physics, one\nmust quantize everything in sight: matter fields, gravitational\nfields,\nand the observer\'s trajectory. If you forget to quantize any of these,\nyou will be in trouble. Which of course everybody working on quantum\ngravity is.\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Mike Helland <mhelland@techmocracy.net> skrev i
diskussionsgruppsmeddelandet:ad157aec.0406150734.5 f9546a7@posting.google.com...
>
> In the two main theories of physics (relativity and quantum) the role
> of observers or observations seems to be pretty important.

Usually I try to avoid thorny interpretational issues, and rather
follow
Feynman's dictum - shut up and calculate. However, understanding the
notion of an observer is an exception, since IMO (but in nobody
else's)
this holds the key to quantum gravity.

>
> Is there text available that rigourously defines these concepts?
>
> Specifically I would like to know if the established thinking is that
> only a human being may observe.

IMO, the important thing is not *what* the observer is, but *where*
she
is. Assuming that the observer is small, she will move around in
spacetime along some timelike curve q(t), presumably a geodesic. The
reason why I think that this is important is the existence of diff
anomalies which are functionals of q(t).

(A diff anomaly is a breakdown of diffeomorphism symmetry, pertinent
to
general relativity. Technically, this is an extension of the
diffeomorphism algebra, i.e. a generalization of the Virasoro algebra
to
several dimensions.)

Now, it is well known that within field theory, there are no diff
anomalies in 4D. This is natural because field theory does not
explicitly involve the observer's trajectory, so there is no way to
formulate these anomalies. Of course, this is the point where
everybody
automatically puts up their noses in the air, say "gauge anomaly" and
shut their ears. Perhaps justly so, but the fact that diff anomalies
exist in 4D if one is willing to slightly relax the field theory
paradigm is rather striking, and indicates perhaps that there is more
to
anomalies than meets the eye.

There is a philosophical problem with specifying a quantum field
throughout spacetime. By doing so, we in some sense assume the role of
a
divine observer who has access to the whole of spacetime, including
events that are separated by spacelike distances. But an observer can
only detect events on her worldline. One way to model this is to
expand
all fields in a Taylor series around q(t) (written in 1D for
simplicity),

f(x) = sum_m f_m(t) (x-q(t))^m .

(The Taylor coefficients f_m(t) must satisfy some additional
conditions
to make f(x) independent of t). Classically at least, physics can be
formulated in terms of Taylor data { q(t), f_m(t) }, rather than the
field data f(x), although this may be awkward in practice and may lead
to convergence problems. Such a formulation allows anomalies depending
on q(t) to arise.

To summarize, my position is that because of the unity of physics, one
must quantize everything in sight: matter fields, gravitational
fields,
and the observer's trajectory. If you forget to quantize any of these,
you will be in trouble. Which of course everybody working on quantum
gravity is.

mandro

Jun22-04, 04:47 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>Mike Helland wrote:\n\n>What I\'m interested in is what is the simplest mechanism\n>that we may describe as an observer. A single molecule, >atom, or even >particle?\n\n\nIn my view, you\'re almost on the right track. I suspect\nthough that ultimately the question of what\'s an observer\n(I mean observer in some platonic sense) may not be\nimportant or even sensical. Then you\'d want a more\nprecise object to replace "observer". now, seeing how\nyou yourself have noticed that a human observer is not\nthe only thing that one can mean by observer, how\'s\nabout this: Ultimately, again you seemed to have noticed\nthis, an observer may be any physical system. Now based\non how this system behaves (i.e., how it looks before and\nafter an interaction) determines the "character" of the\nobservation. Also notice that the complexity of the\nobserver determines the kind of observations that it can\nand cannot make. E.g., if you have an "eye" that has no\nspatial extent, then you may not be able to see angles\nin fact all you\'ll be able to see are points. I mean\nultimately, in most modern theories of physics, observers,\nwhether a human being or a detector, are collections\nof particles (with the possibility of splitting into\nmore particle--i.e., particle creation and annihilation)\nand, what determines if (and how) an observation was made\nis a whole history of the system of particles (Here I\ndeeply suspect that to describe the whole observation I\nneed to include the particles being observed. In other\nwords, you set up a physical model of the observer and\nthe observed as a system of particles, you set up an\ninitial configuration, and then you evolve the system in\ntime and see what develops (I.e., a history of the physical\nsystem) Then, depending on how the observer behaved, you\nsay: "He detected the particle", or "He didn\'t detect the\nparticle". of course, there\'s much more information here\nthan this, because this also contains information on\n"how he detected the particle" I.e., it contains the\ndefinition particular to this particular "observer" for\nwhat it means for it to "detect the particle".\n\n>To get closer to the heart of the matter, I\'ll rephrase\n>a question from my first post:\n>If nature is viewed as a system of interacting bodies can\n>we say that any body may be an "observer" and that any\n>interaction may be an "observation"?\n\n\nYes, almost. But it almost seems like -> V.S.\n<-> . I.e., every observation can be described by\nan interaction, but not every interaction is an\nobservation--at least I\'d say. However, if your\nmain point is that the meaningful, more general\nidea of what an observation is is that it\'s an\ninteraction, I particularly, agree with you.\nOf course the neat thing would be to describe\nmany observation processes with different "model\nobservers" so that one can get more insight into\nthese ideas.\n\n>This appears to be an acceptable claim to me.\n\n--\nMike Helland\nhttp://www.techmocracy.net/science/time.htm\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Mike Helland wrote:

>What I'm interested in is what is the simplest mechanism
>that we may describe as an observer. A single molecule, >atom, or even >particle?

In my view, you're almost on the right track. I suspect
though that ultimately the question of what's an observer
(I mean observer in some platonic sense) may not be
important or even sensical. Then you'd want a more
precise object to replace "observer". now, seeing how
you yourself have noticed that a human observer is not
the only thing that one can mean by observer, how's
about this: Ultimately, again you seemed to have noticed
this, an observer may be any physical system. Now based
on how this system behaves (i.e., how it looks before and
after an interaction) determines the "character" of the
observation. Also notice that the complexity of the
observer determines the kind of observations that it can
and cannot make. E.g., if you have an "eye" that has no
spatial extent, then you may not be able to see angles
in fact all you'll be able to see are points. I mean
ultimately, in most modern theories of physics, observers,
whether a human being or a detector, are collections
of particles (with the possibility of splitting into
more particle--i.e., particle creation and annihilation)
and, what determines if (and how) an observation was made
is a whole history of the system of particles (Here I
deeply suspect that to describe the whole observation I
need to include the particles being observed. In other
words, you set up a physical model of the observer and
the observed as a system of particles, you set up an
initial configuration, and then you evolve the system in
time and see what develops (I.e., a history of the physical
system) Then, depending on how the observer behaved, you
say: "He detected the particle", or "He didn't detect the
particle". of course, there's much more information here
than this, because this also contains information on
"how he detected the particle" I.e., it contains the
definition particular to this particular "observer" for
what it means for it to "detect the particle".

>To get closer to the heart of the matter, I'll rephrase
>a question from my first post:
>If nature is viewed as a system of interacting bodies can
>we say that any body may be an "observer" and that any
>interaction may be an "observation"?

Yes, almost. But it almost seems like -> V.S.
<-> . I.e., every observation can be described by
an interaction, but not every interaction is an
observation--at least I'd say. However, if your
main point is that the meaningful, more general
idea of what an observation is is that it's an
interaction, I particularly, agree with you.
Of course the neat thing would be to describe
many observation processes with different "model
observers" so that one can get more insight into
these ideas.

>This appears to be an acceptable claim to me.

--
Mike Helland
http://www.techmocracy.net/science/time.htm

Ulmo

Jun23-04, 12:36 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\nthomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google. com>...\n> Mike Helland <mhelland@techmocracy.net> skrev i\n> diskussionsgruppsmeddelandet:ad157aec.0406150734.5 f9546a7@posting.google.com...\n> >\n> > In the two main theories of physics (relativity and quantum) the role\n> > of observers or observations seems to be pretty important.\n>\n> Usually I try to avoid thorny interpretational issues, and rather\n> follow\n> Feynman\'s dictum - shut up and calculate.\n\nActually, Feynman never said that, unless you can come up with where\nthe quote is from.\n\n[Moderator\'s note: Probably Thomas Larsson was thinking of this quote:\nhttp://www.jefallbright.net/node/view/916 -usc]\n\nDavid\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>thomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google.com>...
> Mike Helland <mhelland@techmocracy.net> skrev i
> diskussionsgruppsmeddelandet:ad157aec.0406150734.5 f9546a7@posting.google.com...
> >
> > In the two main theories of physics (relativity and quantum) the role
> > of observers or observations seems to be pretty important.
>
> Usually I try to avoid thorny interpretational issues, and rather
> follow
> Feynman's dictum - shut up and calculate.

Actually, Feynman never said that, unless you can come up with where
the quote is from.

[Moderator's note: Probably Thomas Larsson was thinking of this quote:
http://www.jefallbright.net/node/view/916 -usc]

David

Thomas Larsson

Jun24-04, 06:30 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\nulmo@cheerful.com (Ulmo) wrote in message news:<53ca460a.0406221133.79211f39@posting.google. com>...\n> thomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google. com>...\n\n> > Usually I try to avoid thorny interpretational issues, and rather\n> > follow\n> > Feynman\'s dictum - shut up and calculate.\n>\n> Actually, Feynman never said that, unless you can come up with where\n> the quote is from.\n>\n\nhttp://www.physicstoday.org/vol-57/iss-5/p10.html\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>ulmo@cheerful.com (Ulmo) wrote in message news:<53ca460a.0406221133.79211f39@posting.google.com>...
> thomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google.com>...

> > Usually I try to avoid thorny interpretational issues, and rather
> > follow
> > Feynman's dictum - shut up and calculate.
>
> Actually, Feynman never said that, unless you can come up with where
> the quote is from.
>

http://www.physicstoday.org/vol-57/iss-5/p10.html

Alex Green

Jun25-04, 03:46 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>"Harry" <harald.vanlintel@epfl.ch> wrote in message news:<40d02b22\\$1@epflnews.epfl.ch>...\n> > .....\n> > Is there text available that rigourously defines these concepts?\n> >\n> > Specifically I would like to know if the established thinking is that\n> > only a human being may observe. This seems to be a common belief I\n> > see. Is this supported by any hypothesis or literature?\n>\n> Not so. Any sensor or measurement instrument can play the role of an\n> "observer". In many physics experiments no direct human observer is present.\n>\n\nSurely a sensor in a closed system is part of that system and it\'s\nreadings are part of a wavefunction to any external observer.\n\nAn observation is more than an interaction it involves measurement and\nknowledge.\n\nMeasurement is the coding of the state of a system into the state of\nanother system to create \'information\' (eg: 8 values of a variable can\nbe encoded in 3 bits). This information is transmitted to an\n\'observer\'. The information is only a vehicle for conveying a state.\n\nThe information by itself is useless without a lookup table in the\nobserver. A byte encoded as marks on a sheet of paper is just a set of\nmarks without a lookup. It could relate to anything.\n\nLookup tables just convert one symbol to another. In the observer the\nlookup table converts the incoming information into a symbol that can\nbe inserted into a set of relationships. A typical set of\nrelationships is a coordinate system.\n\nThe human observer contains the coordinate system as a geometric form\n(look around you, the physical instantiation of what you see is brain\nactivity, your \'view\' is brain activity as a geometric form).\nObservation is the insertion of the symbol derived from a measurement\ninto an observer\'s manifold of conscious experience so that it can be\nsimultaneously related to the four axes of the observer\'s coordinate\nsystem.\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Harry" <harald.vanlintel@epfl.ch> wrote in message news:<40d02b22$1@epflnews.epfl.ch>...
> > .....
> > Is there text available that rigourously defines these concepts?
> >
> > Specifically I would like to know if the established thinking is that
> > only a human being may observe. This seems to be a common belief I
> > see. Is this supported by any hypothesis or literature?
>
> Not so. Any sensor or measurement instrument can play the role of an
> "observer". In many physics experiments no direct human observer is present.
>

Surely a sensor in a closed system is part of that system and it's
readings are part of a wavefunction to any external observer.

An observation is more than an interaction it involves measurement and
knowledge.

Measurement is the coding of the state of a system into the state of
another system to create 'information' (eg: 8 values of a variable can
be encoded in 3 bits). This information is transmitted to an
'observer'. The information is only a vehicle for conveying a state.

The information by itself is useless without a lookup table in the
observer. A byte encoded as marks on a sheet of paper is just a set of
marks without a lookup. It could relate to anything.

Lookup tables just convert one symbol to another. In the observer the
lookup table converts the incoming information into a symbol that can
be inserted into a set of relationships. A typical set of
relationships is a coordinate system.

The human observer contains the coordinate system as a geometric form
(look around you, the physical instantiation of what you see is brain
activity, your 'view' is brain activity as a geometric form).
Observation is the insertion of the symbol derived from a measurement
into an observer's manifold of conscious experience so that it can be
simultaneously related to the four axes of the observer's coordinate
system.

Mike Helland

Jun27-04, 05:55 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>"Ralph E. Frost" <ralph@REMOVErefrost.com> wrote in message news:<10d3lagnnht5q58@corp.supernews.com>...\n> "Mike Helland" <mhelland@techmocracy.net> wrote in message\n> news:ad157aec.0406162108.289c1c6a@posting.google.c om...\n> >\n> > "Harry" <harald.vanlintel@epfl.ch> wrote in message\n> news:<40d02b22\\$1@epflnews.epfl.ch>...\n> > > "Mike Helland" <mhelland@techmocracy.net> wrote in message\n> > > news:ad157aec.0406150734.5f9546a7@posting.google.c om...\n> >\n> > Thanks for the response.\n> >\n> > <snip>\n> >\n> > > > Is there text available that rigourously defines these concepts?\n> > > >\n> > > > Specifically I would like to know if the established thinking is that\n> > > > only a human being may observe. This seems to be a common belief I\n> > > > see. Is this supported by any hypothesis or literature?\n> > >\n> > > Not so. Any sensor or measurement instrument can play the role of an\n> > > "observer". In many physics experiments no direct human observer is\n> present.\n> >\n> > What I\'m interested in is what is the simplest mechanism that we may\n> > describe as an observer. A single molecule, atom, or even particle?\n> >\n> > To get closer to the heart of the matter, I\'ll rephrase a question\n> > from my first post:\n> >\n> > If nature is viewed as a system of interacting bodies can we say that\n> > any body may be an "observer" and that any interaction may be an\n> > "observation"?\n> >\n> > This appears to be an acceptable claim to me.\n>\n> Might it be better to scrap the idealized notion of "an observer and refer\n> to participants?\n\nWith this I agree completely, and was what was meant by saying\nobservers are any body in an interaction.\n\nPut another way, instead of thinking about observers, which is clearly\ndifficult to define, let us just think about interacting bodies.\n\n\n> Perhaps qualifying futher to participants who can or do\n> report?\n\nThis I am unsure of. Is there a sound reason for complicating what was\njust established above with more subjective or idealized notions like\n"reporting"?\n\nWhat I mean is we can make the argument that interactions involving\nthe ocean floor and currents may be reported by the shape of the ocean\nfloor. The reports are very vague naturally, but they can still be\nsaid to exist. Why not just assume that all bodies participating in\ninteractions may "report" the results of those interactions, though\nperhaps with varying degrees of detail?\n\nJust as a reminder of why these issues are discussion-worthy:\nrelativity and quantum theories both make heavy use of observer and\nobservation and I would like to verify that it is possible to\nunderstand these concepts in their most general meanings. In other\nwords, I would like to be able to understand the ideas without\nassuming a special frame of reference that requires the presence of an\nobserver with a given degree of sophistication.\n\n--\nMike Helland\nhttp://www.techmocracy.net/science/zeno.htm\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Ralph E. Frost" <ralph@REMOVErefrost.com> wrote in message news:<10d3lagnnht5q58@corp.supernews.com>...
> "Mike Helland" <mhelland@techmocracy.net> wrote in message
> news:ad157aec.0406162108.289c1c6a@posting.google.c om...
> >
> > "Harry" <harald.vanlintel@epfl.ch> wrote in message
> news:<40d02b22$1@epflnews.epfl.ch>...
> > > "Mike Helland" <mhelland@techmocracy.net> wrote in message
> > > news:ad157aec.0406150734.5f9546a7@posting.google.c om...
> >
> > Thanks for the response.
> >
> > <snip>
> >
> > > > Is there text available that rigourously defines these concepts?
> > > >
> > > > Specifically I would like to know if the established thinking is that
> > > > only a human being may observe. This seems to be a common belief I
> > > > see. Is this supported by any hypothesis or literature?
> > >
> > > Not so. Any sensor or measurement instrument can play the role of an
> > > "observer". In many physics experiments no direct human observer is
> present.
> >
> > What I'm interested in is what is the simplest mechanism that we may
> > describe as an observer. A single molecule, atom, or even particle?
> >
> > To get closer to the heart of the matter, I'll rephrase a question
> > from my first post:
> >
> > If nature is viewed as a system of interacting bodies can we say that
> > any body may be an "observer" and that any interaction may be an
> > "observation"?
> >
> > This appears to be an acceptable claim to me.
>
> Might it be better to scrap the idealized notion of "an observer and refer
> to participants?

With this I agree completely, and was what was meant by saying
observers are any body in an interaction.

Put another way, instead of thinking about observers, which is clearly
difficult to define, let us just think about interacting bodies.

> Perhaps qualifying futher to participants who can or do
> report?

This I am unsure of. Is there a sound reason for complicating what was
just established above with more subjective or idealized notions like
"reporting"?

What I mean is we can make the argument that interactions involving
the ocean floor and currents may be reported by the shape of the ocean
floor. The reports are very vague naturally, but they can still be
said to exist. Why not just assume that all bodies participating in
interactions may "report" the results of those interactions, though
perhaps with varying degrees of detail?

Just as a reminder of why these issues are discussion-worthy:
relativity and quantum theories both make heavy use of observer and
observation and I would like to verify that it is possible to
understand these concepts in their most general meanings. In other
words, I would like to be able to understand the ideas without
assuming a special frame of reference that requires the presence of an
observer with a given degree of sophistication.

--
Mike Helland
http://www.techmocracy.net/science/zeno.htm

Arnold Neumaier

Jun27-04, 05:59 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>Thomas Larsson wrote:\n\n> To summarize, my position is that because of the unity of physics, one\n> must quantize everything in sight: matter fields, gravitational\n> fields,\n> and the observer\'s trajectory. If you forget to quantize any of these,\n> you will be in trouble. Which of course everybody working on quantum\n> gravity is.\n\nBut there are many observers in the universe, and each one is a complicated\nmacroscopic object. Already in flat Minkowski spacetime, it is dubious to\nassign to a multiparticle system a well-defined trajectory, nad there are\nno-go theorems in fact forbidding this (under certain assumptions,\nof course).\n\n\nArnold Neumaier\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Thomas Larsson wrote:

> To summarize, my position is that because of the unity of physics, one
> must quantize everything in sight: matter fields, gravitational
> fields,
> and the observer's trajectory. If you forget to quantize any of these,
> you will be in trouble. Which of course everybody working on quantum
> gravity is.

But there are many observers in the universe, and each one is a complicated
macroscopic object. Already in flat Minkowski spacetime, it is dubious to
assign to a multiparticle system a well-defined trajectory, nad there are
no-go theorems in fact forbidding this (under certain assumptions,
of course).

Arnold Neumaier

Thomas Larsson

Jun27-04, 06:00 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>ulmo@cheerful.com (Ulmo) wrote in message news:<53ca460a.0406221133.79211f39@posting.google. com>...\n> thomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google. com>...\n> > Mike Helland <mhelland@techmocracy.net> skrev i\n> > diskussionsgruppsmeddelandet:ad157aec.0406150734.5 f9546a7@posting.google.com...\n> > >\n> > > In the two main theories of physics (relativity and quantum) the role\n> > > of observers or observations seems to be pretty important.\n> >\n> > Usually I try to avoid thorny interpretational issues, and rather\n> > follow\n> > Feynman\'s dictum - shut up and calculate.\n>\n> Actually, Feynman never said that, unless you can come up with where\n> the quote is from.\n>\n\nhttp://www.physicstoday.org/vol-57/iss-5/p10.html\n\n(Sorry I this appears twice - Google hang up no me the first time)\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>ulmo@cheerful.com (Ulmo) wrote in message news:<53ca460a.0406221133.79211f39@posting.google.com>...
> thomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google.com>...
> > Mike Helland <mhelland@techmocracy.net> skrev i
> > diskussionsgruppsmeddelandet:ad157aec.0406150734.5 f9546a7@posting.google.com...
> > >
> > > In the two main theories of physics (relativity and quantum) the role
> > > of observers or observations seems to be pretty important.
> >
> > Usually I try to avoid thorny interpretational issues, and rather
> > follow
> > Feynman's dictum - shut up and calculate.
>
> Actually, Feynman never said that, unless you can come up with where
> the quote is from.
>

http://www.physicstoday.org/vol-57/iss-5/p10.html

(Sorry I this appears twice - Google hang up no me the first time)

Arnold Neumaier

Jun27-04, 06:01 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>Ulmo wrote:\n> thomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google. com>...\n>\n>>Feynman\'s dictum - shut up and calculate.\n>\n> Actually, Feynman never said that, unless you can come up with where\n> the quote is from.\n>\n> [Moderator\'s note: Probably Thomas Larsson was thinking of this quote:\n> http://www.jefallbright.net/node/view/916 -usc]\n\nMaybe it was Mernin who coined the phrase, although it is generally\nattributed to Feynman. See Physics Today (May 2004):\nhttp://www.physicstoday.org/vol-57/iss-5/p10.html\n\n\nArnold Neumaier\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Ulmo wrote:
> thomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google.com>...
>
>>Feynman's dictum - shut up and calculate.
>
> Actually, Feynman never said that, unless you can come up with where
> the quote is from.
>
> [Moderator's note: Probably Thomas Larsson was thinking of this quote:
> http://www.jefallbright.net/node/view/916 -usc]

Maybe it was Mernin who coined the phrase, although it is generally
attributed to Feynman. See Physics Today (May 2004):
http://www.physicstoday.org/vol-57/iss-5/p10.html

Arnold Neumaier

Ralph E. Frost

Jun27-04, 06:01 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>"Harry" <harald.vanlintel@epfl.ch> wrote in message\nnews:40d2c92e\\$1@epflnews.epfl.ch...\n>\ n> "Ralph E. Frost" <ralph@REMOVErefrost.com> wrote in message\n> news:10d0fdc42p3f24d@corp.supernews.com...\n> > "Harry" <harald.vanlintel@epfl.ch> wrote in message\n> > news:40d02b22\\$1@epflnews.epfl.ch...\n> > >\n> > > "Mike Helland" <mhelland@techmocracy.net> wrote in message\n> > > news:ad157aec.0406150734.5f9546a7@posting.google.c om...\n> > > >\n> > > > In the two main theories of physics (relativity and quantum) the\nrole\n> > > > of observers or observations seems to be pretty important.\n> > >\n....\n> > Are you referring to the data collection phase? Can you give examples\nof\n> > the types of things you are thinking about?\n>\n> Yes with "direct" I meant the data collection, such as for example a\n> temperature sensor or a CCD camera that sends data to a computer.\n> I know that there are claims that that data can be influenced by the\nthought\n> processes of living species (Princeton PEAR), but I\'m not convinced as\nthere\n> have been no completely independent confirmation to my knowledge.\n>\n\nIf you are interested, you may find confirmation through some of the efforts\nreported at Toward a Science of Consciousness 2004. See\nhttp://consciousness.arizona.edu/\n\n\n--\nRalph Frost\nImagine consciousness as\na single internal analog language\nmade of ordered water...\nand its variants.\nhttp://flep.refrost.com\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Harry" <harald.vanlintel@epfl.ch> wrote in message
news:40d2c92e$1@epflnews.epfl.ch...
>
> "Ralph E. Frost" <ralph@REMOVErefrost.com> wrote in message
> news:10d0fdc42p3f24d@corp.supernews.com...
> > "Harry" <harald.vanlintel@epfl.ch> wrote in message
> > news:40d02b22$1@epflnews.epfl.ch...
> > >
> > > "Mike Helland" <mhelland@techmocracy.net> wrote in message
> > > news:ad157aec.0406150734.5f9546a7@posting.google.c om...
> > > >
> > > > In the two main theories of physics (relativity and quantum) the
role
> > > > of observers or observations seems to be pretty important.
> > >
....
> > Are you referring to the data collection phase? Can you give examples
of
> > the types of things you are thinking about?
>
> Yes with "direct" I meant the data collection, such as for example a
> temperature sensor or a CCD camera that sends data to a computer.
> I know that there are claims that that data can be influenced by the
thought
> processes of living species (Princeton PEAR), but I'm not convinced as
there
> have been no completely independent confirmation to my knowledge.
>

If you are interested, you may find confirmation through some of the efforts
reported at Toward a Science of Consciousness 2004. See
http://consciousness.arizona.edu/

--
Ralph Frost
Imagine consciousness as
a single internal analog language
made of ordered water...
and its variants.
http://flep.refrost.com

Ulmo

Jun27-04, 06:02 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>thomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google. com>...\n> Mike Helland <mhelland@techmocracy.net> skrev i\n> diskussionsgruppsmeddelandet:ad157aec.0406150734.5 f9546a7@posting.google.com...\n> >\n> > In the two main theories of physics (relativity and quantum) the role\n> > of observers or observations seems to be pretty important.\n>\n> Usually I try to avoid thorny interpretational issues, and rather\n> follow\n> Feynman\'s dictum - shut up and calculate.\n\nActually, Feynman never said that, unless you can come up with where\nthe quote is from.\n\nDavid\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>thomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google.com>...
> Mike Helland <mhelland@techmocracy.net> skrev i
> diskussionsgruppsmeddelandet:ad157aec.0406150734.5 f9546a7@posting.google.com...
> >
> > In the two main theories of physics (relativity and quantum) the role
> > of observers or observations seems to be pretty important.
>
> Usually I try to avoid thorny interpretational issues, and rather
> follow
> Feynman's dictum - shut up and calculate.

Actually, Feynman never said that, unless you can come up with where
the quote is from.

David

Thomas Larsson

Jun28-04, 12:10 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n\n\n\nArnold Neumaier <Arnold.Neumaier@univie.ac.at> wrote in message news:<40D8144B.7040308@univie.ac.at>...\n\n> But there are many observers in the universe, and each one is a complicated\n> macroscopic object. Already in flat Minkowski spacetime, it is dubious to\n> assign to a multiparticle system a well-defined trajectory, nad there are\n> no-go theorems in fact forbidding this (under certain assumptions,\n> of course).\n>\n\nA second observer can be regarded as part of the system being\nobserved by the first one. The physics observed by the second\nobserver must of course be the same as the physics observed\nby the first one, which is a highly non-trivial constraint.\nMy point is that it may be necessary to make a choice.\n\nMore mathematically, it doesn\'t matter (in principle) if one\nmakes a Taylor expansion around q or around q\', but if one\nwants to Taylor expand, one must pick some base point.\n\nAs for macroscopic observers with a non-zero spatial extent,\nyou still run into conceptual problems - how can parts of the\nobserver separated by a spacelike distance communicate?\n\nAs my Feynman (or Mermin) quote indicates, I am neither very\ngood at nor interested in interpretational issues, but here\nthe problem kicks me in the face. It is simply a mathematical\nfact that in order to build interesting representations of\nthe diffeomorphism algebra, one must introduce a privileged\n1D curve in spacetime, and expand all fields in a Taylor\nseries around this curve. So what can this curve be apart\nfrom the observer\'s trajectory?\n\nAnother fact is that quantum reps gives rise to extensions,\ni.e. diff anomalies, in any number of dimensions. I think\nthis is rather striking, in view of the well-known fact that\nthere are no diff anomalies in 4D within field theory.\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Arnold Neumaier <Arnold.Neumaier@univie.ac.at> wrote in message news:<40D8144B.7040308@univie.ac.at>...

> But there are many observers in the universe, and each one is a complicated
> macroscopic object. Already in flat Minkowski spacetime, it is dubious to
> assign to a multiparticle system a well-defined trajectory, nad there are
> no-go theorems in fact forbidding this (under certain assumptions,
> of course).
>

A second observer can be regarded as part of the system being
observed by the first one. The physics observed by the second
observer must of course be the same as the physics observed
by the first one, which is a highly non-trivial constraint.
My point is that it may be necessary to make a choice.

More mathematically, it doesn't matter (in principle) if one
makes a Taylor expansion around q or around q', but if one
wants to Taylor expand, one must pick some base point.

As for macroscopic observers with a non-zero spatial extent,
you still run into conceptual problems - how can parts of the
observer separated by a spacelike distance communicate?

As my Feynman (or Mermin) quote indicates, I am neither very
good at nor interested in interpretational issues, but here
the problem kicks me in the face. It is simply a mathematical
fact that in order to build interesting representations of
the diffeomorphism algebra, one must introduce a privileged
1D curve in spacetime, and expand all fields in a Taylor
series around this curve. So what can this curve be apart
from the observer's trajectory?

Another fact is that quantum reps gives rise to extensions,
i.e. diff anomalies, in any number of dimensions. I think
this is rather striking, in view of the well-known fact that
there are no diff anomalies in 4D within field theory.

Alex Green

Jun29-04, 04:35 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>thomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google. com>...\n> Mike Helland <mhelland@techmocracy.net> skrev i\n> diskussionsgruppsmeddelandet:ad157aec.0406150734.5 f9546a7@posting.google.com...\n> >\n> ...............\n> There is a philosophical problem with specifying a quantum field\n> throughout spacetime. By doing so, we in some sense assume the role of\n> a\n> divine observer who has access to the whole of spacetime, including\n> events that are separated by spacelike distances. But an observer can\n> only detect events on her worldline. One way to model this is to\n> expand\n> all fields in a Taylor series around q(t) (written in 1D for\n> simplicity),\n>\n> f(x) = sum_m f_m(t) (x-q(t))^m .\n>\n> (The Taylor coefficients f_m(t) must satisfy some additional\n> conditions\n> to make f(x) independent of t). Classically at least, physics can be\n> formulated in terms of Taylor data { q(t), f_m(t) }, rather than the\n> field data f(x), although this may be awkward in practice and may lead\n> to convergence problems. Such a formulation allows anomalies depending\n> on q(t) to arise.\n>\n\nThis seems to assume that information from events is travelling into\nthe observer. Information is a mobile thing (such as a light wave)\nthat has a (classical) state that is one of a number of states that\nmay exist in some source data. When the information arrives at the\nobserver it alters the (classical) state of a set of things at that\nlocation. These things are still separated by space. What has been\naccomplished is the creation of a model of the original data that\nstill requires observation. Your term x-q(t) suggests a point\nobservation - this would solve the problem but how would this be\naccomplished?\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>thomas_larsson_01@hotmail.com (Thomas Larsson) wrote in message news:<24a23f36.0406220257.3ba45e75@posting.google.com>...
> Mike Helland <mhelland@techmocracy.net> skrev i
> diskussionsgruppsmeddelandet:ad157aec.0406150734.5 f9546a7@posting.google.com...
> >
> ...............
> There is a philosophical problem with specifying a quantum field
> throughout spacetime. By doing so, we in some sense assume the role of
> a
> divine observer who has access to the whole of spacetime, including
> events that are separated by spacelike distances. But an observer can
> only detect events on her worldline. One way to model this is to
> expand
> all fields in a Taylor series around q(t) (written in 1D for
> simplicity),
>
> f(x) = sum_m f_m(t) (x-q(t))^m .
>
> (The Taylor coefficients f_m(t) must satisfy some additional
> conditions
> to make f(x) independent of t). Classically at least, physics can be
> formulated in terms of Taylor data { q(t), f_m(t) }, rather than the
> field data f(x), although this may be awkward in practice and may lead
> to convergence problems. Such a formulation allows anomalies depending
> on q(t) to arise.
>

This seems to assume that information from events is travelling into
the observer. Information is a mobile thing (such as a light wave)
that has a (classical) state that is one of a number of states that
may exist in some source data. When the information arrives at the
observer it alters the (classical) state of a set of things at that
location. These things are still separated by space. What has been
accomplished is the creation of a model of the original data that
still requires observation. Your term x-q(t) suggests a point
observation - this would solve the problem but how would this be
accomplished?

Rahul Jain

Jun30-04, 05:35 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>thomas_larsson_01@hotmail.com (Thomas Larsson) writes:\n\n> However, understanding the notion of an observer is an exception,\n> since IMO (but in nobody else\'s) this holds the key to quantum\n> gravity.\n\nActually, Penrose seems to share that same opinion. He discusses how he\nthinks that the graviton is probably related to decoherence which is\nprobably related to how our minds work. I also believe that this is a\nplausible conjecture.\n\n--\nRahul Jain\nrjain@nyct.net\nProfessional Software Developer, Amateur Quantum Mechanicist\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>thomas_larsson_01@hotmail.com (Thomas Larsson) writes:

> However, understanding the notion of an observer is an exception,
> since IMO (but in nobody else's) this holds the key to quantum
> gravity.

Actually, Penrose seems to share that same opinion. He discusses how he
thinks that the graviton is probably related to decoherence which is
probably related to how our minds work. I also believe that this is a
plausible conjecture.

--
Rahul Jain
rjain@nyct.net
Professional Software Developer, Amateur Quantum Mechanicist

Harry

Jun30-04, 10:05 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n"Mike Helland" <mhelland@techmocracy.net> wrote in message\nnews:ad157aec.0406172322.4d255023@posting .google.com...\nSNIP\n\n> > Might it be better to scrap the idealized notion of "an observer and\nrefer\n> > to participants?\n>\n> With this I agree completely, and was what was meant by saying\n> observers are any body in an interaction.\n>\n> Put another way, instead of thinking about observers, which is clearly\n> difficult to define, let us just think about interacting bodies.\n>\n>\n> > Perhaps qualifying futher to participants who can or do\n> > report?\n>\n> This I am unsure of. Is there a sound reason for complicating what was\n> just established above with more subjective or idealized notions like\n> "reporting"?\n>\n> What I mean is we can make the argument that interactions involving\n> the ocean floor and currents may be reported by the shape of the ocean\n> floor. The reports are very vague naturally, but they can still be\n> said to exist. Why not just assume that all bodies participating in\n> interactions may "report" the results of those interactions, though\n> perhaps with varying degrees of detail?\n>\n> Just as a reminder of why these issues are discussion-worthy:\n> relativity and quantum theories both make heavy use of observer and\n> observation and I would like to verify that it is possible to\n> understand these concepts in their most general meanings. In other\n> words, I would like to be able to understand the ideas without\n> assuming a special frame of reference that requires the presence of an\n> observer with a given degree of sophistication.\n\nThe above reduction of observer to participants may be correct for quantum\nphysics, but it is wrong for relativity theory.\nIn SRT, one can use a freely chosen frame of reference, apart of the\ninteracting bodies.\nFor example the frame of reference for GPS time measurements, the ECI frame,\ndoes not physically exist.\n\nHarald\n\n\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Mike Helland" <mhelland@techmocracy.net> wrote in message
news:ad157aec.0406172322.4d255023@posting.google.c om...
SNIP

> > Might it be better to scrap the idealized notion of "an observer and
refer
> > to participants?
>
> With this I agree completely, and was what was meant by saying
> observers are any body in an interaction.
>
> Put another way, instead of thinking about observers, which is clearly
> difficult to define, let us just think about interacting bodies.
>
>
> > Perhaps qualifying futher to participants who can or do
> > report?
>
> This I am unsure of. Is there a sound reason for complicating what was
> just established above with more subjective or idealized notions like
> "reporting"?
>
> What I mean is we can make the argument that interactions involving
> the ocean floor and currents may be reported by the shape of the ocean
> floor. The reports are very vague naturally, but they can still be
> said to exist. Why not just assume that all bodies participating in
> interactions may "report" the results of those interactions, though
> perhaps with varying degrees of detail?
>
> Just as a reminder of why these issues are discussion-worthy:
> relativity and quantum theories both make heavy use of observer and
> observation and I would like to verify that it is possible to
> understand these concepts in their most general meanings. In other
> words, I would like to be able to understand the ideas without
> assuming a special frame of reference that requires the presence of an
> observer with a given degree of sophistication.

The above reduction of observer to participants may be correct for quantum
physics, but it is wrong for relativity theory.
In SRT, one can use a freely chosen frame of reference, apart of the
interacting bodies.
For example the frame of reference for GPS time measurements, the ECI frame,
does not physically exist.

Harald

Arnold Neumaier

Jul2-04, 04:33 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n\nThomas Larsson wrote:\n> Arnold Neumaier <Arnold.Neumaier@univie.ac.at> wrote in message news:<40D8144B.7040308@univie.ac.at>...\n>\n>\n>>B ut there are many observers in the universe, and each one is a complicated\n>>macroscopic object. Already in flat Minkowski spacetime, it is dubious to\n>>assign to a multiparticle system a well-defined trajectory, and there are\n>>no-go theorems in fact forbidding this (under certain assumptions,\n>>of course).\n>>\n>\n>\n> A second observer can be regarded as part of the system being\n> observed by the first one. The physics observed by the second\n> observer must of course be the same as the physics observed\n> by the first one, which is a highly non-trivial constraint.\n> My point is that it may be necessary to make a choice.\n>\n> More mathematically, it doesn\'t matter (in principle) if one\n> makes a Taylor expansion around q or around q\', but if one\n> wants to Taylor expand, one must pick some base point.\n\nBut the function value at any point must be independent of the\nexpansion point. In your approach you\'d have to prove observer\nindependence before anything objective can be deduced...\n\n\n> As for macroscopic observers with a non-zero spatial extent,\n> you still run into conceptual problems - how can parts of the\n> observer separated by a spacelike distance communicate?\n\nWell, aren\'t you and I observers with spatial extent? And we\ncommunicate, it seems...\n\nKnowledge of an observer (living or inanimate) is a holistic,\nspacially extended phenomenon, not something pointlike.\n\n\n> As my Feynman (or Mermin) quote indicates, I am neither very\n> good at nor interested in interpretational issues, but here\n> the problem kicks me in the face. It is simply a mathematical\n> fact that in order to build interesting representations of\n> the diffeomorphism algebra, one must introduce a privileged\n> 1D curve in spacetime, and expand all fields in a Taylor\n> series around this curve. So what can this curve be apart\n> from the observer\'s trajectory?\n\nJust calling \'it\' an \'observer\' because it is a curve in spacetime\nis playing games. The name \'observer\' is appropriate only if you\ncan set it up in such a way that your \'observer\' actually interacts\nin a way that resembles an observation.\n\nWhatever \'it\' is, objective physical results must be independent\nof it. To make a contribution to physics you must find a way to\nextract curve/observer independent quantities, since only these are\nscientifically communicable.\n\n\nArnold Neumaier\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Thomas Larsson wrote:
> Arnold Neumaier <Arnold.Neumaier@univie.ac.at> wrote in message news:<40D8144B.7040308@univie.ac.at>...
>
>
>>But there are many observers in the universe, and each one is a complicated
>>macroscopic object. Already in flat Minkowski spacetime, it is dubious to
>>assign to a multiparticle system a well-defined trajectory, and there are
>>no-go theorems in fact forbidding this (under certain assumptions,
>>of course).
>>
>
>
> A second observer can be regarded as part of the system being
> observed by the first one. The physics observed by the second
> observer must of course be the same as the physics observed
> by the first one, which is a highly non-trivial constraint.
> My point is that it may be necessary to make a choice.
>
> More mathematically, it doesn't matter (in principle) if one
> makes a Taylor expansion around q or around q', but if one
> wants to Taylor expand, one must pick some base point.

But the function value at any point must be independent of the
expansion point. In your approach you'd have to prove observer
independence before anything objective can be deduced...

> As for macroscopic observers with a non-zero spatial extent,
> you still run into conceptual problems - how can parts of the
> observer separated by a spacelike distance communicate?

Well, aren't you and I observers with spatial extent? And we
communicate, it seems...

Knowledge of an observer (living or inanimate) is a holistic,
spacially extended phenomenon, not something pointlike.

> As my Feynman (or Mermin) quote indicates, I am neither very
> good at nor interested in interpretational issues, but here
> the problem kicks me in the face. It is simply a mathematical
> fact that in order to build interesting representations of
> the diffeomorphism algebra, one must introduce a privileged
> 1D curve in spacetime, and expand all fields in a Taylor
> series around this curve. So what can this curve be apart
> from the observer's trajectory?

Just calling 'it' an 'observer' because it is a curve in spacetime
is playing games. The name 'observer' is appropriate only if you
can set it up in such a way that your 'observer' actually interacts
in a way that resembles an observation.

Whatever 'it' is, objective physical results must be independent
of it. To make a contribution to physics you must find a way to
extract curve/observer independent quantities, since only these are
scientifically communicable.

Arnold Neumaier

Thomas Larsson

Jul6-04, 01:47 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\nArnold Neumaier <Arnold.Neumaier@univie.ac.at> wrote in message news:<40E06841.50200@univie.ac.at>...\n\n> > As for macroscopic observers with a non-zero spatial extent,\n> > you still run into conceptual problems - how can parts of the\n> > observer separated by a spacelike distance communicate?\n>\n> Well, aren\'t you and I observers with spatial extent? And we\n> communicate, it seems...\n\nI observe characters on my computer screen. Although my\noffice isn\'t infinitesimal, its spatial extent is neglible\ncompared to the distance between Stockholm and Vienna.\n\nThis is really my point. Of course I do not doubt that you\nhave typed those characters, but that is not something that I\ncan primarily observe, even in principle. Even if we assume\nthat moderation and newsfeed to Google takes neglible time,\nthe best I can hope for is reading those characters several\nmilliseconds after you typed them, since we are light-\nmilliseconds apart. A physical theory really only needs to\ndescribe primarily observable events.\n\n>\n> Knowledge of an observer (living or inanimate) is a holistic,\n> spacially extended phenomenon, not something pointlike.\n\nObservation is an interaction of quantum systems, since\neverything is. It is not qualitatively different from\ninteractions between presumably pointlike objects like\nelectrons and photons, since that is what observers are built\nfrom.\n\n>\n>\n> > As my Feynman (or Mermin) quote indicates, I am neither very\n> > good at nor interested in interpretational issues, but here\n> > the problem kicks me in the face. It is simply a mathematical\n> > fact that in order to build interesting representations of\n> > the diffeomorphism algebra, one must introduce a privileged\n> > 1D curve in spacetime, and expand all fields in a Taylor\n> > series around this curve. So what can this curve be apart\n> > from the observer\'s trajectory?\n>\n> Just calling \'it\' an \'observer\' because it is a curve in spacetime\n> is playing games. The name \'observer\' is appropriate only if you\n> can set it up in such a way that your \'observer\' actually interacts\n> in a way that resembles an observation.\n\nI\'m not really talking about the act of observation, only\nwhere it takes place. A pointlike curve is a useful\nmathematical abstraction.\n\n>\n> Whatever \'it\' is, objective physical results must be independent\n> of it. To make a contribution to physics you must find a way to\n> extract curve/observer independent quantities, since only these are\n> scientifically communicable.\n\nThe quantum representation theory of the diffeomorphism\nalgebra is IMO a quite solid contribution to mathematics, and\nI\'m trying to understand what the physical implications of\nthis discovery are. Perhaps this will not contribute to\nphysics. But then again, one may argue that nobody contributes\nto fundamental physics these days. The existence of a new\ndiff anomaly is at least a solid mathematical fact, and not\nsome idle matter of interpretation.\n\nIt is of course true that a Taylor series must converge to a\nfield that is independent of the expansion point, and this\nfield must transform in an appropriate way under\ndiffeomorphisms. Apart from questions whether it converges at\nall, this leads to conditions on and transformation laws for\nthe Taylor coefficients. More interestingly, the anomalies\nshould also converge to something finite. This leads to quite\nstringent constraints on the possible field content, and it\nreally works best if spacetime has four dimensions.\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Arnold Neumaier <Arnold.Neumaier@univie.ac.at> wrote in message news:<40E06841.50200@univie.ac.at>...

> > As for macroscopic observers with a non-zero spatial extent,
> > you still run into conceptual problems - how can parts of the
> > observer separated by a spacelike distance communicate?
>
> Well, aren't you and I observers with spatial extent? And we
> communicate, it seems...

I observe characters on my computer screen. Although my
office isn't infinitesimal, its spatial extent is neglible
compared to the distance between Stockholm and Vienna.

This is really my point. Of course I do not doubt that you
have typed those characters, but that is not something that I
can primarily observe, even in principle. Even if we assume
that moderation and newsfeed to Google takes neglible time,
the best I can hope for is reading those characters several
milliseconds after you typed them, since we are light-
milliseconds apart. A physical theory really only needs to
describe primarily observable events.

>
> Knowledge of an observer (living or inanimate) is a holistic,
> spacially extended phenomenon, not something pointlike.

Observation is an interaction of quantum systems, since
everything is. It is not qualitatively different from
interactions between presumably pointlike objects like
electrons and photons, since that is what observers are built
from.

>
>
> > As my Feynman (or Mermin) quote indicates, I am neither very
> > good at nor interested in interpretational issues, but here
> > the problem kicks me in the face. It is simply a mathematical
> > fact that in order to build interesting representations of
> > the diffeomorphism algebra, one must introduce a privileged
> > 1D curve in spacetime, and expand all fields in a Taylor
> > series around this curve. So what can this curve be apart
> > from the observer's trajectory?
>
> Just calling 'it' an 'observer' because it is a curve in spacetime
> is playing games. The name 'observer' is appropriate only if you
> can set it up in such a way that your 'observer' actually interacts
> in a way that resembles an observation.

I'm not really talking about the act of observation, only
where it takes place. A pointlike curve is a useful
mathematical abstraction.

>
> Whatever 'it' is, objective physical results must be independent
> of it. To make a contribution to physics you must find a way to
> extract curve/observer independent quantities, since only these are
> scientifically communicable.

The quantum representation theory of the diffeomorphism
algebra is IMO a quite solid contribution to mathematics, and
I'm trying to understand what the physical implications of
this discovery are. Perhaps this will not contribute to
physics. But then again, one may argue that nobody contributes
to fundamental physics these days. The existence of a new
diff anomaly is at least a solid mathematical fact, and not
some idle matter of interpretation.

It is of course true that a Taylor series must converge to a
field that is independent of the expansion point, and this
field must transform in an appropriate way under
diffeomorphisms. Apart from questions whether it converges at
all, this leads to conditions on and transformation laws for
the Taylor coefficients. More interestingly, the anomalies
should also converge to something finite. This leads to quite
stringent constraints on the possible field content, and it
really works best if spacetime has four dimensions.

Arnold Neumaier

Jul9-04, 03:49 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\nThomas Larsson wrote:\n> Arnold Neumaier <Arnold.Neumaier@univie.ac.at> wrote in message news:<40E06841.50200@univie.ac.at>...\n>\n>\n>>>As for macroscopic observers with a non-zero spatial extent,\n>>>you still run into conceptual problems - how can parts of the\n>>>observer separated by a spacelike distance communicate?\n>>\n>>Well, aren\'t you and I observers with spatial extent? And we\n>>communicate, it seems...\n>\n>\n> I observe characters on my computer screen. Although my\n> office isn\'t infinitesimal, its spatial extent is neglible\n> compared to the distance between Stockholm and Vienna.\n>\n> This is really my point. Of course I do not doubt that you\n> have typed those characters, but that is not something that I\n> can primarily observe, even in principle. Even if we assume\n> that moderation and newsfeed to Google takes neglible time,\n> the best I can hope for is reading those characters several\n> milliseconds after you typed them, since we are light-\n> milliseconds apart. A physical theory really only needs to\n> describe primarily observable events.\n\nOK. But this shows that communication between spatially extended\nobservers is not instantaneous but needs time long enough that their\nspacial extend can be neglected. With this observation,\nthere is no conceptual problem left.\n\n\n>>Knowledge of an observer (living or inanimate) is a holistic,\n>>spacially extended phenomenon, not something pointlike.\n>\n> Observation is an interaction of quantum systems, since\n> everything is. It is not qualitatively different from\n> interactions between presumably pointlike objects like\n> electrons and photons, since that is what observers are built\n> from.\n\nOn the surface, yes. But what do you call an observation?\nThis is not just any interaction, but a somewhat permanent result\nof interactions. This makes the difference. To define permanence\none needs thermodynamics and hence maxroscopic size.\n\n\n>>Just calling \'it\' an \'observer\' because it is a curve in spacetime\n>>is playing games. The name \'observer\' is appropriate only if you\n>>can set it up in such a way that your \'observer\' actually interacts\n>>in a way that resembles an observation.\n>\n> I\'m not really talking about the act of observation, only\n> where it takes place. A pointlike curve is a useful\n> mathematical abstraction.\n\nBut if a pointlike curve makes its appearance on the fundamental level,\nit needs some justification to say that there an \'act of observation\ntakes place\'. This justification is missing so far.\n\n\n>>Whatever \'it\' is, objective physical results must be independent\n>>of it. To make a contribution to physics you must find a way to\n>>extract curve/observer independent quantities, since only these are\n>>scientifically communicable.\n>\n> The quantum representation theory of the diffeomorphism\n> algebra is IMO a quite solid contribution to mathematics,\n\nHmm. Your solid contribution to mathematics that I do not dispute is\nthe construction of representations of abelian extensions of the\ndiffeomorphsim algebra.\n\nWhat is disputable is whether it is a quantum representation.\nIn my opinion one needs a unitary representation in a Hilbert space\nbefore something qualifies for this name. The construction of the inner\nproduct needed for that is still missing in your work. In conformal\nfield theory, it is precisely the unitarity constraint that makes\nthe theory predictive.\n\n\n> It is of course true that a Taylor series must converge to a\n> field that is independent of the expansion point, and this\n> field must transform in an appropriate way under\n> diffeomorphisms. Apart from questions whether it converges at\n> all,\n\nwhich is so far unsettled but important if you want to have your\nmathematical construction contribute to physics...\n\n\n> this leads to conditions on and transformation laws for\n> the Taylor coefficients. More interestingly, the anomalies\n> should also converge to something finite. This leads to quite\n> stringent constraints on the possible field content, and it\n> really works best if spacetime has four dimensions.\n\nYou still need to do the analytical estimates showing that your\nconstruction defines analytic functions.\n\n\nArnold Neumaier\n\n\n\n\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Thomas Larsson wrote:
> Arnold Neumaier <Arnold.Neumaier@univie.ac.at> wrote in message news:<40E06841.50200@univie.ac.at>...
>
>
>>>As for macroscopic observers with a non-zero spatial extent,
>>>you still run into conceptual problems - how can parts of the
>>>observer separated by a spacelike distance communicate?
>>
>>Well, aren't you and I observers with spatial extent? And we
>>communicate, it seems...
>
>
> I observe characters on my computer screen. Although my
> office isn't infinitesimal, its spatial extent is neglible
> compared to the distance between Stockholm and Vienna.
>
> This is really my point. Of course I do not doubt that you
> have typed those characters, but that is not something that I
> can primarily observe, even in principle. Even if we assume
> that moderation and newsfeed to Google takes neglible time,
> the best I can hope for is reading those characters several
> milliseconds after you typed them, since we are light-
> milliseconds apart. A physical theory really only needs to
> describe primarily observable events.

OK. But this shows that communication between spatially extended
observers is not instantaneous but needs time long enough that their
spacial extend can be neglected. With this observation,
there is no conceptual problem left.

>>Knowledge of an observer (living or inanimate) is a holistic,
>>spacially extended phenomenon, not something pointlike.
>
> Observation is an interaction of quantum systems, since
> everything is. It is not qualitatively different from
> interactions between presumably pointlike objects like
> electrons and photons, since that is what observers are built
> from.

On the surface, yes. But what do you call an observation?
This is not just any interaction, but a somewhat permanent result
of interactions. This makes the difference. To define permanence
one needs thermodynamics and hence maxroscopic size.

>>Just calling 'it' an 'observer' because it is a curve in spacetime
>>is playing games. The name 'observer' is appropriate only if you
>>can set it up in such a way that your 'observer' actually interacts
>>in a way that resembles an observation.
>
> I'm not really talking about the act of observation, only
> where it takes place. A pointlike curve is a useful
> mathematical abstraction.

But if a pointlike curve makes its appearance on the fundamental level,
it needs some justification to say that there an 'act of observation
takes place'. This justification is missing so far.

>>Whatever 'it' is, objective physical results must be independent
>>of it. To make a contribution to physics you must find a way to
>>extract curve/observer independent quantities, since only these are
>>scientifically communicable.
>
> The quantum representation theory of the diffeomorphism
> algebra is IMO a quite solid contribution to mathematics,

Hmm. Your solid contribution to mathematics that I do not dispute is
the construction of representations of abelian extensions of the
diffeomorphsim algebra.

What is disputable is whether it is a quantum representation.
In my opinion one needs a unitary representation in a Hilbert space
before something qualifies for this name. The construction of the inner
product needed for that is still missing in your work. In conformal
field theory, it is precisely the unitarity constraint that makes
the theory predictive.

> It is of course true that a Taylor series must converge to a
> field that is independent of the expansion point, and this
> field must transform in an appropriate way under
> diffeomorphisms. Apart from questions whether it converges at
> all,

which is so far unsettled but important if you want to have your
mathematical construction contribute to physics...

> this leads to conditions on and transformation laws for
> the Taylor coefficients. More interestingly, the anomalies
> should also converge to something finite. This leads to quite
> stringent constraints on the possible field content, and it
> really works best if spacetime has four dimensions.

You still need to do the analytical estimates showing that your
construction defines analytic functions.

Arnold Neumaier

Ralph E. Frost

Aug2-04, 06:11 PM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>"Harry" <harald.vanlintel@epfl.ch> wrote in message\nnews:40e2af17\\$1@epflnews.epfl.ch...\n>\ n> "Mike Helland" <mhelland@techmocracy.net> wrote in message\n> news:ad157aec.0406172322.4d255023@posting.google.c om...\n> SNIP\n>\n> > > Might it be better to scrap the idealized notion of "an observer and\n> refer\n> > > to participants?\n> >\n....\n> > Just as a reminder of why these issues are discussion-worthy:\n> > relativity and quantum theories both make heavy use of observer and\n> > observation and I would like to verify that it is possible to\n> > understand these concepts in their most general meanings. In other\n> > words, I would like to be able to understand the ideas without\n> > assuming a special frame of reference that requires the presence of an\n> > observer with a given degree of sophistication.\n>\n> The above reduction of observer to participants may be correct for quantum\n> physics, but it is wrong for relativity theory.\n> In SRT, one can use a freely chosen frame of reference, apart of the\n> interacting bodies.\n> For example the frame of reference for GPS time measurements, the ECI\nframe,\n> does not physically exist.\n\nThis may be a nit-pick but are you having your "observers" issue a report\nor send a signal?\n\nIf they do something other than observe, either in the planning, setup,\nimplementation, analysis/interpretation, or interpersonal communication\nphases, I think you need to notice that they are, in fact, participants, not\njust observers.\n\n\n--\nRalph Frost\nImagine consciousness as\na single internal analog language\nmade of ordered water...\nand its variants.\nhttp://flep.refrost.com\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Harry" <harald.vanlintel@epfl.ch> wrote in message
news:40e2af17$1@epflnews.epfl.ch...
>
> "Mike Helland" <mhelland@techmocracy.net> wrote in message
> news:ad157aec.0406172322.4d255023@posting.google.c om...
> SNIP
>
> > > Might it be better to scrap the idealized notion of "an observer and
> refer
> > > to participants?
> >
....
> > Just as a reminder of why these issues are discussion-worthy:
> > relativity and quantum theories both make heavy use of observer and
> > observation and I would like to verify that it is possible to
> > understand these concepts in their most general meanings. In other
> > words, I would like to be able to understand the ideas without
> > assuming a special frame of reference that requires the presence of an
> > observer with a given degree of sophistication.
>
> The above reduction of observer to participants may be correct for quantum
> physics, but it is wrong for relativity theory.
> In SRT, one can use a freely chosen frame of reference, apart of the
> interacting bodies.
> For example the frame of reference for GPS time measurements, the ECI
frame,
> does not physically exist.

This may be a nit-pick but are you having your "observers" issue a report
or send a signal?

If they do something other than observe, either in the planning, setup,
implementation, analysis/interpretation, or interpersonal communication
phases, I think you need to notice that they are, in fact, participants, not
just observers.

--
Ralph Frost
Imagine consciousness as
a single internal analog language
made of ordered water...
and its variants.
http://flep.refrost.com