Smolin: Anthropery is not science

[marcus]

this just out

An new essay by Smolin, to be a part of a book that Cambridge University Press is publishing (edited by Bernard Carr et al)

http://arxiv.org/hep-th/0407213

"It is explained in detail why the Anthropic Principle cannot yield any
falsifiable predictions and therefore cannot be a part of science."


Smolin offers an alternative that he argues does yield falsifiable predictions which, although it has not so far been shown false, is nevertheless vulnerable to refutation by observations now planned or in progress.

 

[sol2]

this just out

An new essay by Smolin, to be a part of a book that Cambridge University Press is publishing (edited by Bernard Carr et al)

http:arxiv.org/hep-th/0407213

"It is explained in detail why the Anthropic Principle cannot yield any
falsifiable predictions and therefore cannot be a part of science."


Smolin offers an alternative that he argues does yield falsifiable predictions which, although it has not so far been shown false, is nevertheless vulnerable to refutation by observations now planned or in progress.

Did you have a proper link for this Marcus?

 

[marcus]

Did you have a proper link for this Marcus?

There I fixed it, earlier i wrote http:arxiv
instead of http://arxiv .
thanks for getting me to correct it.

Hi sol,
you know I have never gotten much interested in the Anthropic
business in string theory, so i am posting this in case other people
want to discuss it. If no one wants to that's fine with me.

Smolin's article is also about the Multiverse business, how there could
be lots of other regions with different fundamental constants---different alpha, different Lambda---essentially different physical laws.

He has an idea how universes might EVOLVE by those values of alpha and Lambda being favored if they were in the right range to cause the universe to have a long life and make lots of baby universes-----good genes are those that get passed on a lot.

Again I have to say that this idea may be a fascinating one but I didnt personally get involved with it. It may actually be an experimentally testable theory explaining why our alpha is what it is: very close to 1/137 (which happens to be so good for the existence of complex life and long-burning stars.) but I put it out just in case it might interest others.

the paper is called

"an alternative to the anthropic principle"

the link should work now

 

[Chronos]

I find that unpalatable. The anthropic principle, I believe, is the only 'given' that is absolute. The fact we are here [and I presume most everyone will agree with that] precludes solutions that forbid our existence. I'm not excluding the possibility of universes where creatures, such as us, do not exist. Just excluding the possibility they are relevant.

 

[sol2]

Thanks Marcus

The Anthropic Landscape of String Theory

Leonard Susskind

Leonard Susskind

In this lecture I make some educated guesses, about the landscape of string theory vacua. Based on the recent work of a number of authors, it seems plausible that the lanscape is unimaginably large and diverse. Whether we like it or not, this is the kind of behavior that gives credence to the Anthropic Principle. I discuss the theoretical and conceptual issues that arise in developing a cosmology based on the diversity of environments implicit in string theory.

http://arxiv.org/abs/hep-th/0302219

On page 11 Smolin's article also refers to the use of the word Landscape?

Of course we all like to have proof of all these theoretics.

 

[Chronos]

Ranting. I object to using unobserved extra dimensions to explain the four we can observe. Apologies to all. I am old, stubborn, and won't let go of background independent relativity until somebody sticks the observational evidence in my face.

 

[Chronos]

More ranting: I wasted 4 years of my life trying to prove Einstein was wrong [keyword: wasted]. He was not wrong. Even his 'cosmological constant' was totally on target. Einstein saw more than we even dreamt of seeing.

I really get frustrated when the truly brilliant people here go off on tangents. What a waste of brain power. I will never be as smart as you guys. I lurk in the background and watch.

 

[marcus]

More ranting: I wasted 4 years of my life trying to prove Einstein was wrong [keyword: wasted]. He was not wrong. Even his 'cosmological constant' was totally on target. Einstein saw more than we even dreamt of seeing.
...

Hello Chronos, let's not quarrel about Anthropism. I for one am not concerned with it. (however Smolin may have some useful points to make, why not read his essay?)

I think all he is saying is that a scientific theory is meaningful only to the extent that it is falsifiable---runs the risk of making predictions which can cause it to be shot down.

so a principle can be a valid part of Philosophy and of one's system of beliefs without necessarily being a part of science. this is a rather strict idea of Science but at least it is clear---a scientific theory is meaningful only to the extent that it is vulnerable to empirical refutation.

I'm cool with that, I have a number of important tenets and faiths and convictions that are not empirically testable. Also i like certain poems.
It is obvious to me this is an absolutely wonderful universe and very conducive to a happy wholesome life (if we could just get our act together).

So I propose to believe whatever you say in an Anthropic vein---to agree with you wholeheartedly----but not to consider it part of science. Do you think we can manage that in a spirit of peace and fellowship (if some problem with it please say)

are you claiming Curmudgeon status BTW? this is or should be a position of high honor

 

[Olias]

More ranting: I wasted 4 years of my life trying to prove Einstein was wrong [keyword: wasted]. He was not wrong. Even his 'cosmological constant' was totally on target. Einstein saw more than we even dreamt of seeing.

I really get frustrated when the truly brilliant people here go off on tangents. What a waste of brain power. I will never be as smart as you guys. I lurk in the background and watch.

Einstein was more than right, but I believe that his 'wrong' lines of workings were actually deliberate! May be due to the surrounding Human and scientific worldwide problems of the day. Some of the so called greatest minds of early last century mocked Einstein and his 'later years', the much quoted sentence of:Einstein wasted the later years of his life working on an Unified Field Theory, which yeilded no scientific fruits?

Or...did he?

It is no coincedence that Some of Einsteins greatest work is placed in specific writings, "Time-locked" for "future" generations hidden (so presicely) between the pages of the very distinct book , which has the title:Albert Einstein-Out Of My Later Years.

This is Einsteins Magnum-Opus, ..you just have to read its content in a certain way..with the awe of a Child of unbiased learning.

 

[selfAdjoint]

For recent work on the Unified Field Theory by a professional physicist, see
http://www.einstein-schrodinger.com/.

 

[marcus]

Ranting. I object to using unobserved extra dimensions to explain the four we can observe. Apologies to all. I am old, stubborn, and won't let go of background independent relativity until somebody sticks the observational evidence in my face.

I thought about making this my sig
(as a quote from you)
I wouldn't excuse it as ranting though, Or apologize
for steadfast rejection of the unobserved.

In one of the historical parts of Rovelli's book he argues that
major scientific advances have not been achieved, as a rule,
by "Great Leaps of Imagination" but actually in a conservative
manner by taking seriously what you already had that worked
and modifying it only as much as you had to.

One of his examples was 1905 Special rel---something about
taking seriously both galilean relativity and Maxwell equations
and not wanting to let go of either-----and not going for novelty
but simply making the minimum modification necessary (different time for
different folks) to get consistency. I'm not sure I got this right
but there is a philosophical part of that book that argues for this
kind of conservative taking seriously the core of what works and
avoiding the Wild Goose of novelty.

It struck me as a good motto so I tried to imagine it as a sig.
The following is a test (not a real sig)

---------
What extra dimensions? I'll hold to background independent relativity until observational evidence shows it wrong.
---Chronos

 

[sol2]

Any one of us could be the negative and from that, a position taken.


I like Olias's perspective on what could have "spaces inbetween" and find that in future years Einstein's implication still reverberating(what is the dimensional significance of this statement if we consider Ramaujan view about the reality we live) and holding a collider eye to the very fabric. I mean we take reductionistic processes and we find this vast field of energy, being really fuzzy, we had only gone so far to Planck length? So we had to explain the energy? Some particle trails leave us wondering and the rest of the energy?

So what lies beneath? Geometrically, the necessity of consistancy, cries for some continuance, expressed logically. What had been learned so far in these extension through this historical journey? Can LQG and M Theory succeed in this quest?

Are we so wrong then, if we look at emergent realities that one might have built glass palaces for living theoretcally in , while we look at all the rooms? I do not think we should all be faulted at trying to explain this reality, and at the same time find discoveries along the way.

Smolin recognizes the philosphcal journey that must be taken and speaks to the rational and logical requirement such journies must take. Much like Peter Woit on demands for scientific validation require a more fundamental approach, but still to me, the imaginiative valution of theoretical journies are quite artistical embued. You have to be creative as well as logical. I think the etiquette of scientifdic pursuate is generally well understood.

We do not discard the anomalies of perception(Kuhn) that cause great consternation in what is wrong with our views, that we set it all aside becuase it just doesn't make sense. You plug away. Some did not not find the connecting circumstance so they discard the view.

My statement should read opposite Marcus's and I admire Marcus determinations. The Solvay format is very much alive when we accept the spirit of it

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

What extra dimensions? I'll hold to the background dependant

 

[Njorl]

I find that unpalatable. The anthropic principle, I believe, is the only 'given' that is absolute. The fact we are here [and I presume most everyone will agree with that] precludes solutions that forbid our existence. I'm not excluding the possibility of universes where creatures, such as us, do not exist. Just excluding the possibility they are relevant.

Please be aware that there are many anthropic principles. They run the gamut from simple common sense to the metaphysical. I haven't looked carefully, but the author might only be assailing the cosmological anthropic principle, as espoused by Barrow and Tipler.

Njorl

 

[sol2]

So again Smolin Takes us to the Edge?

You have to understand his mode of operandi? There is always this proverbial headshaking that goes on, and a consolidation of factors, when you become spread out? Sort of like a greg egans Gravity well picture?


http://citebase.eprints.org/cgi-bin/search?submit=1;author=Smolin%2C%20Lee

An assessment is offered of the progress that the major approaches to quantum gravity have made towards the goal of constructing a complete and satisfactory theory. The emphasis is on loop quantum gravity and string theory, although other approaches are discussed, including dynamical triangulation models (euclidean and lorentzian) regge calculus models, causal sets, twistor theory, non-commutative geometry and models based on analogies to condensed matter systems. We proceed by listing the questions the theories are expected to be able to answer. We then compile two lists: the first details the actual results so far achieved in each theory, while the second lists conjectures which remain open. By comparing them we can evaluate how far each theory has progressed, and what must still be done before each theory can be considered a satisfactory quantum theory of gravity. We find there has been impressive recent progress on several fronts. At the same time, important issues about loop quantum gravity are so far unresolved, as are key conjectures of string theory. However, there is a reasonable expectation that experimental tests of lorentz invariance at Planck scales may in the near future make it possible to rule out one or more candidate quantum theories of gravity.

http://citebase.eprints.org/cgi-bin/citations?id=oai:arXiv.org:hep-th/0303185

So we are back to Earth and have taken our heads out of the clouds have we? Its funny how you can look up at the clouds and see this changing reality, and if you look hard enough, for sure, there seems to be this animal or that face?

If men/women could see to the very heart of the matters(laughlin, Einstein[slide of light]Feynman[integral paths]), what allowed them the greater vision, to pick out what exists in nature(patterns), to know with all that information at hand, they could have seen something else?

Do anomalies of perception pay off? Maybe Einstein asks us to look deeper?They most certainly do in science

 

[marcus]

Smolin introduced the "Landscape" in 1995

It is interesting to note that Lenny Susskind and other string theorists have recently (essentially since Kachru's paper and the 10¹⁰⁰ possible string vacuums) become converts to Smolin's 1995 idea of
the "Landscape" of possible parameters of the Standard Model----essentially an evolutionary landscape of possibility for the laws of physics.

I went back to Smolin's landmark 1995 paper where he introduced the concept of the Landscape

http://arxiv.org/gr-qc/9505022
Cosmology as a problem in critical phenomena
Lee Smolin
(see page 33)

"...We can then make predictions about our world if there are statistical predictions that can be made about the properties of randomly chosen members of this ensemble. We can do this because this theory is isomorphic to models of biological evolution, in which natural selection is described in terms of the evolution of probability distributions on fitness landscapes.

As a result there is a natural mechanism of cosmological self- organization, that is formally analogous to biological natural selection. It goes like this. We may consider the space of parameters of low energy physics to be analogous to the space of genes. On this space there is a “fitness” function, which is the average number of black holes produced by a region of the universe that expands from a bounce.

Now, just like the fitness functions of biology, this function is strongly variable, as I said in our universe it is quite large, and there are simple astrophysical arguments that tell us that with many values of the parameters it will be much smaller. The reason the fitness function is strongly variable is worth mentioning: it is that it is not easy to make a black hole. In our universe, a black hole can only be made if a large amount of matter can be compressed into a very small space, and for this to happen there must be rather special circumstances. The fact that this happens at least once a century in each galaxy..."

the more I see of Smolin's work the more it impresses me

In 1995 he is talking about quantum gravity removing the Black Hole singularity and replacing it by a quantum bounce that continues into an extension of our spacetime which (because of the horizon) we can't detect signals from and which may therefore be considered (if one wishes) as another universe---one with parameters (fundamental constants) to some extent inherited from ours.

And dammit if yesterday that postdoc Leonardo Modesto didn't go and put up his paper which uses quantum gravity to eliminate the Black Hole singularity and replace the classical ex-singularity with a bounce---and a continuation of spacetime.

But the stringers didnt go Landsc ape AFAIK
until
S. Kachru, R. Kallosh, A. Linde, S. P. Trivedi, de Sitter Vacua in String Theory hep-th/0301240
that is, until january 2003
and even then they seem to be appealing to Anthropery!

Smolin saw the landscape in 1995 and called it a landscape by analogy
with the pre-existing concept in Evolutionary Biology
(which does not require the Anthropic Principle!)

 

[sol2]

You have to remember Marcus, that each one of these guys is being influence by the scholarly envirnoment around them. This does not limit them to branches, but forces them tospeak to new starting points in their considerations.

They are all trying to describe the same thing but in different ways?

Some like Chernekov's version, and is pleasing to the color palette of experienece? Some like pure abstractness.

Pretend you were raised in the wild and had never seen straight lines?

 

[sol2]

It is interesting to note that Lenny Susskind and other string theorists have recently (essentially since Kachru's paper and the 10¹⁰⁰ possible string vacuums) become converts to Smolin's 1995 idea of
the "Landscape" of possible parameters of the Standard Model----essentially an evolutionary landscape of possibility for the laws of physics.

I went back to Smolin's landmark 1995 paper where he introduced the concept of the Landscape

http://arxiv.org/gr-qc/9505022
Cosmology as a problem in critical phenomena
Lee Smolin
(see page 33)

"...We can then make predictions about our world if there are statistical predictions that can be made about the properties of randomly chosen members of this ensemble. We can do this because this theory is isomorphic to models of biological evolution, in which natural selection is described in terms of the evolution of probability distributions on fitness landscapes.

As a result there is a natural mechanism of cosmological self- organization, that is formally analogous to biological natural selection. It goes like this. We may consider the space of parameters of low energy physics to be analogous to the space of genes. On this space there is a “fitness” function, which is the average number of black holes produced by a region of the universe that expands from a bounce.

Now, just like the fitness functions of biology, this function is strongly variable, as I said in our universe it is quite large, and there are simple astrophysical arguments that tell us that with many values of the parameters it will be much smaller. The reason the fitness function is strongly variable is worth mentioning: it is that it is not easy to make a black hole. In our universe, a black hole can only be made if a large amount of matter can be compressed into a very small space, and for this to happen there must be rather special circumstances. The fact that this happens at least once a century in each galaxy..."

the more I see of Smolin's work the more it impresses me

In 1995 he is talking about quantum gravity removing the Black Hole singularity and replacing it by a quantum bounce that continues into an extension of our spacetime which (because of the horizon) we can't detect signals from and which may therefore be considered (if one wishes) as another universe---one with parameters (fundamental constants) to some extent inherited from ours.

And dammit if yesterday that postdoc Leonardo Modesto didn't go and put up his paper which uses quantum gravity to eliminate the Black Hole singularity and replace the classical ex-singularity with a bounce---and a continuation of spacetime.

But the stringers didnt go Landsc ape AFAIK
until
S. Kachru, R. Kallosh, A. Linde, S. P. Trivedi, de Sitter Vacua in String Theory hep-th/0301240
that is, until january 2003
and even then they seem to be appealing to Anthropery!

Smolin saw the landscape in 1995 and called it a landscape by analogy
with the pre-existing concept in Evolutionary Biology
(which does not require the Anthropic Principle!)

It is important for me to see the sequence of events as they are unfolding for you Marcus, and by looking to Baez, you are true to form with guiding principals?

John Baez
String theorists are pragmatic in a certain sense: they don't mind using a background, and they don't mind doing what physicists always do: approximating a divergent series by the sum of the first couple of terms. But this attitude doesn't solve everything, because right now in string theory there is an enormous "landscape" of different backgrounds, with no firm principle for choosing one. Some estimates guess there are over 10100. Leonard Susskind guesses there are 10500, and argues that we'll need the anthropic principle to choose the one describing our world:

http://math.ucr.edu/home/baez/week206.html

 

[Ontoplankton]

This is exactly what I was complaining about earlier, in the "not even wrong" thread. Smolin claims the anthropic principle isn't falsifiable. Of course it isn't: it's an epistemological or decision-theoretical principle, not a contingent claim about the physical world. The question whether it's valuable is a philosophical, not scientific question. The same is true of the "principle of mediocrity".

Okay, so then we can read Smolin as saying that it's theories like eternal inflation, with its multiverse, that aren't falsifiable. But then he claims that non-falsifiable theories should automatically be taken as false. I think this is bizarre: we have no business telling nature how to behave, and whether a theory is experimentally testable has no bearing on whether it's actually true (though of course, the more tests a theory passes, the more likely it is to be correct).

The rest of the paper left a bad taste in my brain as well. I'm not convinced Smolin's reproducing-universes theory is any more falsifiable than e.g. eternal inflation: (IIRC) he refers to the fact that under his theory "almost all" universes should have parameters optimized for black hole production. This seems like a dubious claim to me, given that (IIRC) there are infinitely many universes under his theory, making "almost all" a difficult concept. More importantly: he can't claim that observing different parameters would falsify his theory, because our universe could be one of the exceptions. Such an observation would make his theory less probable, but then we're out of Popper-land and into Bayesian probability theory and decision theory, which is IMO the only place where all these anthropic questions make sense in the first place (Smolin doesn't even mention it).

It looks to me like Smolin misunderstands the relevance of Weinberg's explanation of the cosmological constant as well. It's not just that the cosmological constant can be predicted from the observed fact that there are galaxies; we can explain the CC by the anthropic principle because all the observers in the universes with too high cosmological constants just aren't there.

Smolin dismisses the "doomsday argument" as ridiculous because of an objection that is dealt with in the first entry of the FAQ and another that is dealt with in question 6. All this leads me to think he hasn't even bothered to read up on what philosophers think on the subject (or googled for a minute). He's much more fanatical than the strength of his arguments allows, just like in his book Three Roads to Quantum Gravity (which I recall as having interesting science content but trying to force badly-argued philosophy on me).

Blegh. Sorry for ranting.

 

[sol2]

Onto,

You have to understand this is a cosmological view that had to be defined, and this is being looked at in different ways?

If critical density of OMega is being established, then what is happenng to our unverse? Remember we are talking about billions of years here and the universe has allowed us to consider the dynamics taking place.

You must undertsand where Smoln and those of LQG(SRians) have placed themselves in their attempts at discribing the nature of this universe and how M theory(GRaniums-members of the http://astrosun.tn.cornell.edu/courses/astro201/images/merc_adv.gif ) is doing likewise. These are the new flower children of science

 

[marcus]

This is exactly what I was complaining about earlier, in the "not even wrong" thread. Smolin claims the anthropic principle isn't falsifiable. Of course it isn't:...

I am trying to sort this out. here are some quotes. Let's be sure we are all talking about the same AP and understand Smolin's critique of it:

"I have chosen a deliberatively provocative title, in order to communicate a sense of frustration I’ve felt for many years about how otherwise sensible people, some of whom are among the scientists I most respect and admire, espouse an approach to cosmological problems that is easily seen to be unscientific. I am referring of course to the anthropic principle. By calling it unscientific I mean something very specific, which is that it fails to have a necessary property to be considered a scientific hypothesis. This is that it be falsifiable. According to Popper[1], a theory is falsifiable if one can derive from it unambiguous predictions for doable experiments such that, were contrary results seen, at least one premise of the theory would have been proven not to apply to nature."

"...I also have no argument against straightforward consideration of selection effects, so long as the conditions invoked are known independently and not part of a speculative theory that is otherwise unsupported by any evidence. I will discuss this in some detail below, but the short version is that there simply is a vast logical difference between taking into account a known fact, such as the fact that most of the galaxy is empty space, and arguing from a speculative and unproven premise, such as that there is a large ensemble of unseen universes.

In recent discussions, the version of the anthropic principle that is usually put forward by its proponents as a scientific idea is based on two premises.

• A There exists (in the same sense that our chairs, tables and our universe exists) a very large ensemble of “universes”, M which are completely or almost completely causally disjoint regions of spacetime, within which the parameters of the standard models of physics and cosmology differ. To the extent that they are causally disjoint, we have no ability to make observations in other universe than our own. The parameters of the standard models of particle physics and cosmology vary over the ensemble of universes.

• B The distribution of parameters in M is random (in some measure) and the parameters that govern our universe are rare.

This is the form of the Anthropic Principle most invoked in discussions related to inflationary cosmology and string theory, and it is the one I will critique here. Here is the basic argument why a theory based on A and B is not falsifiable..."

Onto, Chronos, sol, and others, are we all talking about the same thing in this thread? If so, let's proceed.

 

[marcus]

Onto you said in post #18
"Okay, so then we can read Smolin as saying that it's theories like eternal inflation, with its multiverse, that aren't falsifiable. But then he claims that non-falsifiable theories should automatically be taken as false."

Where in the paper does he claim that?

we shouldn't attribute claims to the author that he doesn't make,
so you probably have a particular paragraph or sentence in mind,
please point it out since i can't find it

 

[Ontoplankton]

Onto, Chronos, sol, and others, are we all talking about the same thing in this thread? If so, let's proceed.

We are. What Smolin calls the anthropic principle isn't actually the anthropic principle; it's the theory that there is a multiverse where different universes have different constants etc. and only some of them allow for the existence of physicists. In the rest (after the first paragraph) of my post, this version of the anthropic principle was what I was talking about.

 

[Ontoplankton]

Onto you said in post #18
"Okay, so then we can read Smolin as saying that it's theories like eternal inflation, with its multiverse, that aren't falsifiable. But then he claims that non-falsifiable theories should automatically be taken as false."

Where in the paper does he claim that?

Okay, that wasn't a direct quote; I take it back.

However, he does say e.g.:

"scientists have an ethical imperative to consider only falsifiable theories as possible explanations of natural phenomena",

which IMO comes down to the same thing.

 

[setAI]

Okay, that wasn't a direct quote; I take it back.

However, he does say e.g.:

"scientists have an ethical imperative to consider only falsifiable theories as possible explanations of natural phenomena",

which IMO comes down to the same thing.

but he doesn't say non-falsifiable theories are false- just not part of SCIENCE- which is axiomatic given the definition of science- the fundamental eternal/infinite nature of the Universe is another example of such an idea- one I would claim is both necissarily TRUE and at the same time UNSCIENTIFIC due to unfalsifiability

Smolin is a scientist- therefore he wants to deal with scientific ideas- not existential/ontological tautologies- ideas for philosophers and artists to explore- this is where I COME IN

___________________________

/:set\AI transmedia laboratories

http://setai-transmedia.com

 

[Ontoplankton]

Stupid thought:

The theory that our universe is infinite is falsifiable: if we found an edge, or if we found out it's topologically weird so that it goes in circles (in all directions), then the theory would be falsified.

The theory that our universe is finite is unfalsifiable. After all, to falsify the theory, we would need to prove it's infinite, and there's no way to do that.

Therefore, by Smolin's reasoning, all talk of finite universes is unscientific. Scientists have an ethical imperative (!) to not even consider the possibility that the universe might be finite.

Popperianism is really weird.

(edit: this isn't completely fair, of course, but it's almost fair. Popper-abuse is very easy, and I think Smolin falls for it a few times.)

 

[sol2]

Brane New World and the House of Cards

Thank you Marcus in helping to oreintate one back to a clear definition.


A lot of different things are popping into my mind on this issue, so I am finding myself all over the map. I hope you will be patient, because something seems to be metasizing in my brain in regard to this issue.

We have been presented with a way in which to discern the responsible feature and etiquette of science, as I once mentioned before.

So keeping your post in mind, things like solitons and discriptive ways in which this could be attacked in the brane scenarios and the cyclical nature of the cosmos seems to hold a logical position in my mind.

What was "nothing" and can such a universe ever have arisen from such a position? So to me something from nothing is nothing, and from that position, a certain logic said to me that I had to accept that the universe has always existed.

In doing that, I came to realize that such cyclical universe had a advantage, and such singularities no longer seemed a viable function and the potentials of dynamics within the context of the universe had a place in the perspective of the Life Cycles of Energy and Matter. This is a leading perspective on the nature of reality being defined from a starting point in terms of geometrical principals, and here such a question to have differential geometry arising from the understanding of the standard model from the brane very appealing? Brane intersections as descirbe in the analogy of the Moire effect?

But how will we ever see such dynamics in the hidden dimensions. So indeed something begins to form in mind about the nature of this reality and its possibilties.

http://physicsweb.org/objects/review/14/12/1/pw1412r1.gif

The anthropic principle is one of the more remarkable swindles in physics. Indeed it is metaphysics, and that is the essence of the problem for most physicists in accepting it. The anthropic logic is either immensely subtle, by arguing that we, via our mere existence, control the cosmos, or unabashedly naive, by setting aside any physics explanations that any ultimate theory of physics might reasonably be expected to deliver. Metaphysics lacks predictive power, the very core of physics. The anthropic principle is an extreme expression of our ignorance.

It may well be that the ultimate theory of cosmology will have anthropic ramifications. We are some way yet from this promised land. In the meantime, Hawking's book is a delight to read. It discusses questions that are at the forefront of current thinking about quantum gravity, yet for the most part is highly readable. It conveys the author's sense of wonder and awe at the cosmos, and - like a child stepping into the darkness - illustrates his tentative gropings towards the ultimate theory of everything.

http://physicsweb.org/article/review/14/12/1/1

One had to see where these early indications of perspective views had been arising from, and from a nutshell how was he seeing before Hawking's absolution in the GR17? Is there one of coming clean?

So this brings us back to ways in which to measure a responsible features underlying reality, and this is where two perspective views are saying which is more responsible?

 

[marcus]

The theory that our universe is infinite is falsifiable

Is this a theory? I do not understand what you mean by a scientific theory. General Relativity is a theory and it does not predict infinite, nor does it predict finite. It is not a premise of GR that the U is infinite. It is also not a premise of GR that the U is finite.

Finite and infinite are conclusions that one can draw, with a certain confidence level, from certain measurements using a scientific theory---namely Relativity.

The theory that our universe is finite is unfalsifiable. .

But again I have to ask, is it a scientific THEORY that the universe is finite? What good is using the phrase "the theory that our universe is finite" if, as I suspect, it does not refer to anything. There is, AFAIK, no such thing as a theory that U is finite---would have to make predictions and what prediction could it make? Theories have more parts to them than such an assertion.

Therefore, by Smolin's reasoning, all talk of finite universes is unscientific. Scientists have an ethical imperative (!) to not even consider the possibility that the universe might be finite.

Not true, one can test Relativity and within the context of that theory one can interpret measurements as implying the U is finite. The measurable parameter Omega, is it greater than 1? Unfortunately at the moment it is estimated at 1.02 +/- 0.02 and one cannot say for sure that it is >1
but someday we may be able to. Suppose next year the measurement says 1.02 +/- 0.01 (then with fair confidence we would be able to say finite as one of the conclusions of GR.) But finite is not the THEORY. Relativity is the theory and there are various ways to test it and within that context one can make statements derived from the theory using measurements.

OK maybe what you said was a joke, your suggests.

Popper-abuse is very easy, and I think Smolin falls for it a few times.

At what place in the essay does Smolin make a mistake? Please quote some lines from the essay that we can inspect.

Popperianism is really weird.

But Onto, you have not yet exhibited anything weird about what Smolin says! Let's focus on the essay and see if any of us can find anything wrong or out of line with it. So far your comments seem intended for fun. I appreciate the playfulness, but I would be glad if someone could find some substantial mistake in the essay.

BTW So far I haven't found anything out of line, but if I come across anything at all doubtful i will let y'all know. Wd like a critical reading of the essay on its own merits.

 

[marcus]

Thank you Marcus in helping to oreintate one back to a clear definition.

well I'm trying to sort it out as best as I can---and thanks in turn for your part!

my feeling there's no one right definition of any of these key words like scientific and anthropic. There's no one definition that will be right in all situations, but I have a strong urge to read this essay with some other people and to read it on its own terms-----understand it is saying with Smolins definitions.

BTW I am willing to believe and disbelieve a lot of things that aren't part of science! That's part of being human----you believe the universe is beautiful, that your wife has a good sense of humor, that a certain choral work is great and fun to sing, that your child is clever and charming and so on----or that a certain historian had the right perspective on the middle ages---or in some moral principles---that the US is or ought to be a constitutional representative democracy---it goes on endlessly

But the touchstone of a scientific theory is prediction allowing it to be tested. And for me this is just commonplace accepted truth I've heard all my life----dont need a philosopher to approve it! And Smolin uses this idea without needing to appeal to any authority. He gives a reasonable social argument of his own which makes sense.
The point about the scientific community is they can get agreement by empirical tests.

they arent like theologians who split up into various parties and sects and schools of thought

Everybody in the community, for the sake of the community's longterm cohesion and solidarity, should make sure not to propose theories that can't be tested. And the possibility of testing means the possibility of being shot down.

there can be other things: conjectures, scenarios, theories a-building which are under construction and not yet making predictions---but the goal is to get something falsifiable. always. until it is falsifiable it does not mean anything because it does not bet its life on a prediction about the world.

I think Smolin is saying that, and it makes sense to me.

And I think of Einstein publishing Gen Rel in 1915 and predicting that the light would be bent a certain angle, and by 1919 Eddington had gone to that island and looked and checked the angle---for a strange theory like that four years is not bad. this is the tradition and I think Smolin is there.

 

[setAI]

Stupid thought:

The theory that our universe is infinite is falsifiable: if we found an edge, or if we found out it's topologically weird so that it goes in circles (in all directions), then the theory would be falsified.

nope- all this would do is suggest that our universe [little u] was finite- the eternal/infinite Multiverse/Metaverse hypothesis [really an axiom] still remains and [as Spinoza demonstrated long ago- reiterated by Hegel] the existence of an eternal/infinite Universe [big U: the whole of Existence] is unavoidable given that there is Existence at all - this is what I am referring to as the "eternal/infinite nature of the Universe" [big U]

I personly have a feeling that universes are finite and curve back on themselves anyway- although ours is probably quintillions of light years in extent- the reason I feel this is becasue it seems more likely that finite spacetimes are imbedded in even larer finte structures/dimensional manifolds- just the hierarchy is infinite- not the members of the hierarchy-


Martin Rees explains these ideas all quite thouroughly: http://www.edge.org/3rd_culture/rees03/rees_index.html

___________________________

/:set\AI transmedia laboratories

http://setai-transmedia.com

 

[Haelfix]

The topology of the universe is an open question, though there are strong hints from COBE/WMAP that indeed it is topologically a flat plane.

By the universe here I mean the whole shebang, not just the visible part.

It could still be something like a torus, in which case presumably one day the theory would be falsifiable, but incidentally there are other potential ways to measure global topology.

The hope in astrophysics was that quantum gravity would someday isolate one solution that was at worst the simplest and at best unique, such that we wouldn't have to worry about waiting potentially billions of years before we could be confident about what we live in.

Alas, that's still work in progress.

Btw I agree the anthropic principle should be taken in its simplest form, ie a simple data point. The whole nonsense about statistical ensembles and what not strikes me as metaphysics and not something we should be spending our time worrying about.

We'll either figure it out one day, or we won't, but until we exhaust all avenues of science I don't plan on taking up philosophy or astrology just yet.