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Charlie Stromeyer Jr.
May13-04, 06:49 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>First, I would like to say "Hi" to Lubos and Urs and to thank them for\nbeing two of the moderators of this newsgroup.\n\nFor those of you who may not know, Lubos was the first person to\nanalytically prove Hod\'s conjecture about the quasinormal modes of\nblack holes, and later I will post about what QNMs may mean in\ndetermining whether it is even feasable for dS space to contain a\nfinite dimensional Hilbert space, i.e. unless somebody else has\nalready posted on this topic.\n\nIn the meantime, let us consider a question which may be even more\ndifficult :-)\n\nSpeaking of analytical proofs, I once tried to figure out whether\nacausal effects can arise in the non-local string theories (NLSTs)\nfirst described in [1] because I wanted to use such knowledge for\ndemonstrating the superiority of Maldacena\'s version of holography vs.\nany potential axiomatic QFT versions of holography such as those of\nRehren.\n\nHowever, before I could see an answer to the question of acausal\neffects I noticed that U. Trittman had found that Maldacena\'s\nconjecture is superior by instead using numerical simulations, and\nthen I forgot about the acausality question.\n\nNow, though, I am reminded of this issue about acausality because\nsomeone referred me to a brief four page paper which descibes a\nrelatively simple experiment showing that the wavefunction in QM is\nboth non-local and non-sequential [2].\n\n(Additionally, there are reasons to think that quantum computation, in\none particular case based upon geometric phase or Berry phase, is\nextra-dynamical which means that the process of quantum computation\ncan transcend the usual dynamical and linear time evolution of a\nquantum system [3]).\n\nBack in 1997, I told M. Bershadsky (who was at Harvard U. at the time)\nthat I had once read that Richard Feynman thought that wave-particle\nduality was the most fundamental aspect of QM, and I also told\nBershadsky some speculations about using T-duality on the worldsheet\nto try to derive the wave-particle duality of QM.\n\nHowever, such speculations were fruitless because I could not figure\nout how to get SUSY to work in my scenario to derive the wave-particle\nduality needed for fermions, and nor was I sure if I could really\ncapture the non-locality of QM.\n\nNow, I know better and that a more fundamentally noncommutative\napproach would be needed. However, perhaps N. Seiberg is _too_ smart\nbecause, as I seem to recall, he thought of how stringy effects can\ncancel out acausality in at least one of his models about NC fields\n:-)\n\nMore seriously, though, paper [2] seems to imply that string theory\nhas to be compatible with not just the non-local behavior of the\nwavefunction in QM but also with its non-sequential behavior.\n\nWhat appeals to me about the NLSTs in [1] is that they are non-local\nboth in spacetime and on the worldsheet, and so do you think that\nNLSTs would be the best string theory framework to start with for then\nthinking about potential non-sequential or acausal effects? (It has\nbeen about three years since I have thought about any potential\nacausality in string theory physics.)\n\n\n[1] http://arxiv.org/abs/hep-th/0105309\n\n[2] http://arxiv.org/abs/quant-ph/0102109\n\n[3] http://arxiv.org/abs/quant-ph/0005069\n\nsee also http://arxiv.org/abs/quant-ph/0010081\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">&nbsp;&nbsp;View this Usenet post in original ASCII form </a></div><P></jabberwocky>First, I would like to say "Hi" to Lubos and Urs and to thank them for
being two of the moderators of this newsgroup.

For those of you who may not know, Lubos was the first person to
analytically prove Hod's conjecture about the quasinormal modes of
black holes, and later I will post about what QNMs may mean in
determining whether it is even feasable for dS space to contain a
finite dimensional Hilbert space, i.e. unless somebody else has
already posted on this topic.

In the meantime, let us consider a question which may be even more
difficult :-)

Speaking of analytical proofs, I once tried to figure out whether
acausal effects can arise in the non-local string theories (NLSTs)
first described in [1] because I wanted to use such knowledge for
demonstrating the superiority of Maldacena's version of holography vs.
any potential axiomatic QFT versions of holography such as those of
Rehren.

However, before I could see an answer to the question of acausal
effects I noticed that U. Trittman had found that Maldacena's
conjecture is superior by instead using numerical simulations, and
then I forgot about the acausality question.

Now, though, I am reminded of this issue about acausality because
someone referred me to a brief four page paper which descibes a
relatively simple experiment showing that the wavefunction in QM is
both non-local and non-sequential [2].

(Additionally, there are reasons to think that quantum computation, in
one particular case based upon geometric phase or Berry phase, is
extra-dynamical which means that the process of quantum computation
can transcend the usual dynamical and linear time evolution of a
quantum system [3]).

Back in 1997, I told M. Bershadsky (who was at Harvard U. at the time)
that I had once read that Richard Feynman thought that wave-particle
duality was the most fundamental aspect of QM, and I also told
Bershadsky some speculations about using T-duality on the worldsheet
to try to derive the wave-particle duality of QM.

However, such speculations were fruitless because I could not figure
out how to get SUSY to work in my scenario to derive the wave-particle
duality needed for fermions, and nor was I sure if I could really
capture the non-locality of QM.

Now, I know better and that a more fundamentally noncommutative
approach would be needed. However, perhaps N. Seiberg is _too_ smart
because, as I seem to recall, he thought of how stringy effects can
cancel out acausality in at least one of his models about NC fields
:-)

More seriously, though, paper [2] seems to imply that string theory
has to be compatible with not just the non-local behavior of the
wavefunction in QM but also with its non-sequential behavior.

What appeals to me about the NLSTs in [1] is that they are non-local
both in spacetime and on the worldsheet, and so do you think that
NLSTs would be the best string theory framework to start with for then
thinking about potential non-sequential or acausal effects? (It has
been about three years since I have thought about any potential
acausality in string theory physics.)


[1] http://arxiv.org/abs/http://www.arxiv.org/abs/hep-th/0105309

[2] http://arxiv.org/abs/http://www.arxiv.org/abs/quant-ph/0102109

[3] http://arxiv.org/abs/http://www.arxiv.org/abs/quant-ph/0005069

see also http://arxiv.org/abs/http://www.arxiv.org/abs/quant-ph/0010081


--------------

Charlie Stromeyer Jr.
May16-04, 12:27 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>"Charlie Stromeyer Jr." &lt;cstromey@hotmail.com&gt; wrote in message news:\n\n&gt; [2] http://arxiv.org/abs/quant-ph/0102109\n&gt;\n&gt; [3] http://arxiv.org/abs/quant-ph/0005069\n&gt;\n&gt; see also http://arxiv.org/abs/quant-ph/0010081\n\nAs many of you already know, to better try to understand the physics\nof non-locality such as stringy fuzziness (aka the spacetime\nuncertainty principle for both open and closed strings), theorists\nexamined and developed noncommutative geometry within the context of\nstring theory.\n\nSooner or later, if theorists want to try to better understand the\nfundamentally acausal nature of QM such as discussed in the above\npapers then perhaps theorists will consider turning to non-associative\ngeometry and its generalizations.\n\nI once posted a list of quite a few references and a few speculations\non the subject of non-associativity in QM and string theory over in\nsci.physics.research under my then current internet pseudonym "zirkus"\n(but I let that old Google account expire and so I started this new\naccount instead).\n\nHere is the original post and also see the followups at the bottom:\n\nhttp://www.lns.cornell.edu/spr/2003-02/msg0048479.html\n\nWhen I have more available time later, I hope to return to considering\nfurther about the potential role for non-associativity in string\ntheory physics and also how it might be related to acausality.\n\nIn the meantime, if anyone else wants to try thinking about this\nsubject then have at it :-)\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">&nbsp;&nbsp;View this Usenet post in original ASCII form </a></div><P></jabberwocky>"Charlie Stromeyer Jr." <cstromey@hotmail.com> wrote in message news:

> [2] http://arxiv.org/abs/http://www.arxiv.org/abs/quant-ph/0102109
>
> [3] http://arxiv.org/abs/http://www.arxiv.org/abs/quant-ph/0005069
>
> see also http://arxiv.org/abs/http://www.arxiv.org/abs/quant-ph/0010081

As many of you already know, to better try to understand the physics
of non-locality such as stringy fuzziness (aka the spacetime
uncertainty principle for both open and closed strings), theorists
examined and developed noncommutative geometry within the context of
string theory.

Sooner or later, if theorists want to try to better understand the
fundamentally acausal nature of QM such as discussed in the above
papers then perhaps theorists will consider turning to non-associative
geometry and its generalizations.

I once posted a list of quite a few references and a few speculations
on the subject of non-associativity in QM and string theory over in
sci.physics.research under my then current internet pseudonym "zirkus"
(but I let that old Google account expire and so I started this new
account instead).

Here is the original post and also see the followups at the bottom:

http://www.lns.cornell.edu/spr/2003-02/msg0048479.html

When I have more available time later, I hope to return to considering
further about the potential role for non-associativity in string
theory physics and also how it might be related to acausality.

In the meantime, if anyone else wants to try thinking about this
subject then have at it :-)