Quantum Spacetime

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Main Question or Discussion Point

Do you believe that in Quantum Gravity, quantization of gravity is only a small part and it is really Quantum Spacetime or the unification of Matter, Space and Time that is the general feature or attraction?
 

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  • #2
marcus
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Do you believe that in Quantum Gravity, quantization of gravity is only a small part and it is really Quantum Spacetime or the unification of Matter, Space and Time that is the general feature or attraction?
Different approaches to QG differ in style and in their basic premises.
The Loop program started with the premise that gravity = geometry.

Understanding gravity means to understand how spacetime geometry interacts with matter. Matter affects the curvature or shape, and the shape influences how matter moves.

So the Loop program has always aimed at a quantum theory of spacetime geometry. Alternatively, a quantum theory of spatial geometry with some handle on how that evolves in time---e.g. transition amplitudes.

That is the paramount goal.

Some of the earliest results, back in the early to mid 1990s were to define geometric measurement operators as quantum observables: the area measuring operator, the volume operator, the angle operator. There is a Hilbert space of quantum states of geometry, and these observables are operators defined on that Hilbert space.

One of the ongoing research efforts is aimed at including matter. There are some recent papers on including fermions. PCT symmetry. I forget the details. There's one by Muxin Han and Carlo Rovelli. It's work in progress. They have to connect matter to geometry interactively. Ideally matter and geometric relationships should arise from the same mathematical ground, be different aspects of the same thing. But that is a distant and elusive goal. Better to try to stay approximately in the present. The current status is that only very rudimentary "toy" matter is being included in the Loop gravity models. Like scalar fields, or a generic fermion.
 
  • #3
atyy
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Gravity=spacetime, so quantum gravity is about quantum spacetime.

The two flavours are does quantum spacetime exist all the way down (eg. old fashioned loop quantum gravity, Rovellian spin foams, asymptotic safety, causal dynamical triagulations) or do quantum spacetime and quantum matter together spring from a more fundamental quantum degree of freedom (string theory).
 
  • #4
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Is there a possibility that quantum mechanics and general relativity are classical limits of a third theory that can no longer be described by any known mathematics? For example, an idea or thought or dream can't be described by mathematics. What if the Final Theory involves ingredient similar to it that can no longer be modeled by mathematics? Is this possible?
 
  • #5
atyy
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Is there a possibility that quantum mechanics and general relativity are classical limits of a third theory that can no longer be described by any known mathematics? For example, an idea or thought or dream can't be described by mathematics. What if the Final Theory involves ingredient similar to it that can no longer be modeled by mathematics? Is this possible?
At present, all attempts at quantum gravity assume quantum mechanics continues to hold.

There are ideas that maybe quantum mechanics itself should fail, but I don't know of any widely studied proposals. http://arxiv.org/abs/quant-ph/0611047 speculates that unitary time evolution shouldn't hold. http://arxiv.org/abs/0711.0757 is another attempt to give up some elements of quantum mechanics.
 
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  • #6
marcus
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Is there a possibility that quantum mechanics and general relativity are classical limits of a third theory that can no longer be described by any known mathematics? For example, an idea or thought or dream can't be described by mathematics. What if the Final Theory involves ingredient similar to it that can no longer be modeled by mathematics? Is this possible?
Varon there is a difficulty with the question itself. The difficulty is that mathematics is a self-creating language which is constantly growing. It has no fixed borders. So you might have something that is not readily described by "any known mathematics"---and 20 years later the language might have evolved so that it can express the idea, describe the data, derive the prediction or whatever it needs to do.

So it is risky to try to say what is NOT possible. I mean in the evolution of physics as a mathematical science in the Empirical tradition. Physics is not especially hampered or limited or constrained by the fact that it is a mathematical science, because math language is always growing.

To illustrate, this week Muxin Han gave this talk at the Loops 2011 conference. 100 years ago these concepts were not part of mathematics. The spinfoam is a concept of something that is not spacetime but is the underlying degrees of freedom which describe or give rise to spacetime. The Feynman diagram (a way of describing particle field behavior) also did not exist 100 years ago, and was not part of mathematics. Muxin Han is finding that at some level the spinfoam and the Feynman diagram are the same thing, or part of the same thing. This was not mathematics a few decades ago, and now it is mathematics:
****
Spinfoam Fermions.
Muxin Han
M. Ambientales Room. Tuesday, May, 24th, 14:45 - 15:05.
Abstract:
We discuss fermion coupling in the framework of spinfoam quantum gravity. We analyze the gravity-fermion spinfoam model and its fermion correlation functions. We show that there is a spinfoam analog of PCT symmetry for the fermion fields on spinfoam model, where a PCT theorem is proved for spinfoam fermion correlation functions. We compute the determinant of the Dirac operator for the fermions, where two presentations of the Dirac determinant are given in terms of diagram expansions. We compute the fermion correlation functions and show that they can be given by Feynman diagrams on the spinfoams, where the Feynman propagators can be represented by a discretized path integral of a world-line action along the edges of the underlying 2-complex.
****

What limits physics ultimately not its mathematical language, but rather it is the guiding rule of the 4 centuries old Empirical tradition founded by Francis Bacon (a Londoner contemporary of William Shakespeare).

The Baconian tradition says that any theory must make unmistakable predictions that one can check, so one can have a chance of shooting it down if it is wrong. You have to be able to derive clear unambiguous conclusions about some future experiment. A theory is not Empirical (in the Baonian tradition) unless it is testable.

One motive physicists have for formulating their theories in math language is that it facilitates this. It helps you express the theory in a model from which you can derive definite predictions, suitable for testing. And there are gray areas---there are principles, and provisional borderline concepts too, that are not testable themselves but used in a tentative or heuristic way to arrive at models that are. However arrived at, ultimately it comes down to experiments, or astronomical observations---confronting the model with data to check if it is right.
 
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  • #7
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Varon there is a difficulty with the question itself. The difficulty is that mathematics is a self-creating language which is constantly growing. It has no fixed borders. So you might have something that is not readily described by "any known mathematics"---and 20 years later the language might have evolved so that it can express the idea, describe the data, derive the prediction or whatever it needs to do.

So it is risky to try to say what is NOT possible. I mean in the evolution of physics as a mathematical science in the Empirical tradition. Physics is not especially hampered or limited or constrained by the fact that it is a mathematical science, because math language is always growing.

To illustrate, this week Muxin Han gave this talk at the Loops 2011 conference. 100 years ago these concepts were not part of mathematics. The spinfoam is a concept of something that is not spacetime but is the underlying degrees of freedom which describe or give rise to spacetime. The Feynman diagram (a way of describing particle field behavior) also did not exist 100 years ago, and was not part of mathematics. Muxin Han is finding that at some level the spinfoam and the Feynman diagram are the same thing, or part of the same thing. This was not mathematics a few decades ago, and now it is mathematics:
****
Spinfoam Fermions.
Muxin Han
M. Ambientales Room. Tuesday, May, 24th, 14:45 - 15:05.
Abstract:
We discuss fermion coupling in the framework of spinfoam quantum gravity. We analyze the gravity-fermion spinfoam model and its fermion correlation functions. We show that there is a spinfoam analog of PCT symmetry for the fermion fields on spinfoam model, where a PCT theorem is proved for spinfoam fermion correlation functions. We compute the determinant of the Dirac operator for the fermions, where two presentations of the Dirac determinant are given in terms of diagram expansions. We compute the fermion correlation functions and show that they can be given by Feynman diagrams on the spinfoams, where the Feynman propagators can be represented by a discretized path integral of a world-line action along the edges of the underlying 2-complex.
****

What limits physics ultimately not its mathematical language, but rather it is the guiding rules of the 4 centuries old Empirical tradition founded by Francis Bacon (a Londoner contemporary of William Shakespeare).

The Baconian tradition says that any theory must make predictions that one can check, so one can have a chance of shooting it down if it is wrong. A theory is not Empirical (in the Baonian tradition) unless it is testable.

One motive physicists have for formulating their theories in math language is that it lets you express the theory in model from which you can derive definite predictions, suitable for testing. And there are gray areas and provisional borderline concepts too, that are not testable theories but are used in a tentative or heuristic way to arrive at models. But ultimately it comes down to experiments, or astronomical observations, to check something to see if it is right.
So everything can be modeled by math. How about subjective conscious experience like watching a sunset and feeling awed by it. Can this be modeled by math? If not. Why? How do you distinguish between things that can be modeled by it and things that can't?
 
  • #8
marcus
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So everything can be modeled by math. How about subjective conscious experience like watching a sunset and feeling awed by it. Can this be modeled by math? If not. Why? How do you distinguish between things that can be modeled by it and things that can't?
You misrepresent what I said. I don't use math to describe everything. What you are suggesting is silly. I have lots of channels of expression and experience. I sing choral music, I write poems, I walk up the hill and watch the clouds or the sunset. I am awed mornings when I go out into our garden where evolution of plants and insects and birds is taking place, driven by the sunlight which warms my back, as I eat a sandwich full of solar energy that has been transformed by living things into my food. As far as I'm concerned nature and the universe are awesome and both physics and biology help me appreciate that and i don't need math to describe the awe. I can sing it to music if I want, or dance it if I'm feeling spry, or whatever.

You are not contradicting, or challenging anything AFAICS.

I will repeat what I said:
===========
Your original question did not make sense to me because it treated math as a limited fixed language. Could physics evolve to something math can't handle?
The question is hard to answer because math does not have a fixed essence, it can expand creatively, so 100 years from now it will be able to describe stuff it cant describe now, and we cannot predict how it will develop.

Basically what keeps physicists using math models is not that they have an algebra compulsion or hidebound obsession with calculus---what keeps them at it is the Baconian tradition.

Empiricism. Math models have definite unambiguous consequences, that nobody can deny follow from the model, and that you can test conclusively. Songs and other pieces of music do not. Poems do not. Mystical religious visions do not. They can describe aspects of the world, often very well, or one's subjective experience---but you don't get to derive undeniable consequences that destroy the poem or the song or the religion if the predicted thing doesn't happen.
==============

Please don't misconstrue what I'm saying. This is not to say that Empirical science is better than Poetry. It just means they are different, with different standards, different paths of evolution, and survival fitness criteria. Tradition matters in both cases. I feel protective about both traditions---the 400 year old Baconian code of science ethics and the 4000 year old tradition of poetry going back, say, to the Sumerian city of Ur where some Old Testament legends may have originated.

We need both traditions and it is the job of each generation to keep them both vital.
 
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  • #9
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You misrepresent what I said. I don't use math to describe everything. What you are suggesting is silly. I have lots of channels of expression and experience. I sing choral music, I write poems, I walk up the hill and watch the clouds or the sunset. I am awed mornings when I go out into our garden where evolution of plants and insects and birds is taking place, driven by the sunlight which warms my back, as I eat a sandwich full of solar energy that has been transformed by living things into my food. As far as I'm concerned nature and the universe are awesome and both physics and biology help me appreciate that and i don't need math to describe the awe. I can sing it to music if I want, or dance it if I'm feeling spry, or whatever.

You are not contradicting, or challenging anything AFAICS.

I will repeat what I said:
===========
Your original question did not make sense to me because it treated math as a limited fixed language. Could physics evolve to something math can't handle?
The question is hard to answer because math does not have a fixed essence, it can expand creatively, so 100 years from now it will be able to describe stuff it cant describe now, and we cannot predict how it will develop.

Basically what keeps physicists using math models is not that they have an algebra compulsion or hidebound obsession with calculus---what keeps them at it is the Baconian tradition.

Empiricism. Math models have definite unambiguous consequences, that nobody can deny follow from the model, and that you can test conclusively. Songs and other pieces of music do not. Poems do not. Mystical religious visions do not. They can describe aspects of the world, often very well, or one's subjective experience---but you don't get to derive undeniable consequences that destroy the poem or the song or the religion if the predicted thing doesn't happen.
==============

Please don't misconstrue what I'm saying. This is not to say that Empirical science is better than Poetry. It just means they are different, with different standards, different paths of evolution, and survival fitness criteria. Tradition matters in both cases. I feel protective about both traditions---the 400 year old Baconian code of science ethics and the 4000 year old tradition of poetry going back, say, to the Sumerian city of Ur where some Old Testament legends may have originated.

We need both traditions and it is the job of each generation to keep them both vital.
You don't get what I'm saying. Let me explain. Supposed, just for sake of discussion, the universe is just an idea, a dream or expression of a Platonic realm. How do you use math to describe "an idea"? It seems you can't. So it means at a certain point (theoretically speaking), math can no longer be used because the Final Theory would be beyond math or mere idea or a dream. Something like that.
 
  • #11
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But according to the Platonist view math is just the realm of ideas.

You should read
http://en.wikipedia.org/wiki/Mathematical_universe_hypothesis
http://arxiv.org/abs/0704.0646
Bad choice of words. I just wanna say what if the universe were an idea or dream of say God. How do you mathematically describe this Final Theory. But I replace God with Platonic realm to avoid the G word and make it more scientific but this ends up not quite well. So for sake for discussion. Eliminate the platonic label, and just assume that an idea, a thought creates the universe. Can this Final Theory be based on math?
 
  • #12
Fra
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Bad choice of words. I just wanna say what if the universe were an idea or dream of say God.
I'd say that's God's problem, not mine ;)

I'll describe my "dreams" and leave others the pleasure of worrying about theirs.

I don't quite see the rationale in the question. Mathematics in physics is really just a language for quantifying things, in particular observations and predictions. Such as quantifying the odds of something. Mathematics is a human thing, but quantification can be physical encoded by physical states.

Something that human scientists can't quantify (describe by mathematics) are probably not something that influences our decision making anyway.

/Fredrik
 
  • #13
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I'd say that's God's problem, not mine ;)

I'll describe my "dreams" and leave others the pleasure of worrying about theirs.

I don't quite see the rationale in the question. Mathematics in physics is really just a language for quantifying things, in particular observations and predictions. Such as quantifying the odds of something. Mathematics is a human thing, but quantification can be physical encoded by physical states.

Something that human scientists can't quantify (describe by mathematics) are probably not something that influences our decision making anyway.

/Fredrik
Steven Weinberg mentioned the Final Theory would be purely mathematical. So I guess you all agree it would still be describable by mathematics. Good if it is. But further beyond the Final Theory.. i guess that's when you can no longer describe it by math. My question is what if the non-math realm is even projected down to say Quantum Gravity. Supposed QM and GR are classical limits of a third theory that is directly descended from beyond the Final Theory. Then there is a possibility that even quantum gravity is no longer mathematical?
 
  • #14
tom.stoer
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Look at the real numbers which are a region within the math realm. There are only countably many real numbers that can be constructed, or described, e.g. using an algorithm (b/c there are only countably many algorithms). So given a real number it cannot be constructed using maths with probability equal to one, and there is no other way but to write it down ... an infinite string of digits w/o any chance to say what comes next. So there is no mathematical method (shortcut) to describe this number, and this applies to nearly every real number.

Now let's say that a physical theory is nothing else but a map of functions from spacetime (whatever that means) to the real numbers (as results of measurements). Now I do not care about a specific theory but I am talking about the space of all possible theories, e.g. about the set of all such functionals mapping spacetime to the reals. It can be proven that the cardinality of this set is even larger than the cardinality of the real numbers itself.

That means that the probability of picking a functional (a theory) that can be constructed is zero. I hope it becomes clear what i mean: the chance to identify a mathematical structure that provides more than an unstructured collection of ignorance is zero.

The funny thing is that we can prove this using math.
 
  • #15
marcus
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Steven Weinberg mentioned the Final Theory would be purely mathematical. So I guess you all agree it would still be describable by mathematics. Good if it is. But further beyond the Final Theory.. i guess that's when you can no longer describe it by math. My question is what if the non-math realm is even projected down to say Quantum Gravity. Supposed QM and GR are classical limits of a third theory that is directly descended from beyond the Final Theory. Then there is a possibility that even quantum gravity is no longer mathematical?
Tom's post suggests that a "Final Theory" might very well not exist----just, at best, a progression of better and better theories.

Theories are human artifacts, we cannot know our future and we may continue to improve our theories without ever reaching a final one.

If there is no Final, then there is nothing "beyond" Final. The words "beyond Final" are meaningless.

And why do you say "beyond Final" would be "no longer describable by math"?

What is mathematics? You cannot say what it is or what it may become in future. You cannot specify its limits.

Math is one possible extension of human language. It happens to be adapted to formulating empirical models and it keeps on evolving and growing.

=====================

As far as we know, mathematics has a purely human significance. It is a human creation, just like spoken languages: like Greek, or French, or Chinese.

It has no universal significance, any more than, say English does. It would be foolish to try to base a theology on considerations of a human artifact, or so I think anyway.

It seems to me that you Varon are ill-advisedly "groping for gaps". We frequently encounter people searching for a Gap where their idea of God can sit. They try this or that Gap as a temporary place to situate a gap-god idea. It seems to me a futile and inept exercise.

So you Varon seem to fall into this pattern: currently exploring the imagined Gap which is "beyond" the nebulous idea of the "Final Theory". The latter might very well not exist and would in any case be a human artifact formulated in some future extension of human language.

==============================

I find it more interesting to speculate about the existence of aliens. :biggrin:


Could there be other living organisms which have for instance....

...well, might some of them, say, if they exist, have discovered Planck's constant?

Does Planck's constant have a kind of rough approximate cross-cultural universality? In the sense that something like it eventually gets discovered a lot of times by various other forms of life (if there are any.)
 
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  • #16
It's strange in a way that mathematics predicts (and proves) that there are things that can't be solved using mathematics.
 
  • #17
marcus
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It's strange in a way that mathematics predicts (and proves) that there are things that can't be solved using mathematics.
That works for a specific version or type of mathematics. Like axiomatic set theory, or the construction of the system of real numbers based on axiomatic set theory. That is a great basis for mathematics. And it can describe its own limitations! (An admirable achievement.)

But I am skeptical of the assumption that the extension of human language called mathematics will always be based on axiomatic set theory.
==================

I would rather change what you said to read "known mathematics as it is today predicts (and proves) that there are things that can't be solved using known mathematics as it is today."

I don't feel that I can make statements about 22nd century mathematics, because I can't foresee well enough what it will be like. Nor can I anticipate the mathematics of an alien civilization (if any exist and if any of them have something we would call math.) These things are fun to speculate about but it is risky to make grand universal pronouncements about them when one really doesn't know the boundaries.

I could be wrong. Maybe Tom has a better grasp. Maybe one can make universal statements valid for all time about this kind of thing, but I feel reluctant to at present.
 
  • #18
That works for a specific version or type of mathematics. Like axiomatic set theory, or the construction of the system of real numbers based on axiomatic set theory. That is a great basis for mathematics. And it can describe its own limitations! (An admirable achievement.)

But I am skeptical of the assumption that the extension of human language called mathematics will always be based on axiomatic set theory.
==================

I would rather change what you said to read "known mathematics as it is today predicts (and proves) that there are things that can't be solved using known mathematics as it is today."

I don't feel that I can make statements about 22nd century mathematics, because I can't foresee well enough what it will be like. Nor can I anticipate the mathematics of an alien civilization (if any exist and if any of them have something we would call math.) These things are fun to speculate about but it is risky to make grand universal pronouncements about them when one really doesn't know the boundaries.

I could be wrong. Maybe Tom has a better grasp. Maybe one can make universal statements valid for all time about this kind of thing, but I feel reluctant to at present.
Don't you think physics gives concrete examples of this, i.e. the system describing it's own limitations.

Jon Baez talk about the state of maximum ignorance in http://golem.ph.utexas.edu/category/2010/11/stateobservable_duality_part_3.html.

Cosmological/particle/black hole horizons put a restriction on much of the universe we can observe,

and then there's quantum indeterminacy.

I think all these problems are related to the idea of boundaries and their relations to observers. The more the observer wants to know, the more boundaries become defined, the less an observer wants to know, the less boundaries there seems to be.

Perhaps, the more an observer knows ,the more entropy they have to cope with..
 
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  • #19
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Tom's post suggests that a "Final Theory" might very well not exist----just, at best, a progression of better and better theories.

Theories are human artifacts, we cannot know our future and we may continue to improve our theories without ever reaching a final one.

If there is no Final, then there is nothing "beyond" Final. The words "beyond Final" are meaningless.

And why do you say "beyond Final" would be "no longer describable by math"?

What is mathematics? You cannot say what it is or what it may become in future. You cannot specify its limits.

Math is one possible extension of human language. It happens to be adapted to formulating empirical models and it keeps on evolving and growing.

=====================

As far as we know, mathematics has a purely human significance. It is a human creation, just like spoken languages: like Greek, or French, or Chinese.

It has no universal significance, any more than, say English does. It would be foolish to try to base a theology on considerations of a human artifact, or so I think anyway.

It seems to me that you Varon are ill-advisedly "groping for gaps". We frequently encounter people searching for a Gap where their idea of God can sit. They try this or that Gap as a temporary place to situate a gap-god idea. It seems to me a futile and inept exercise.

So you Varon seem to fall into this pattern: currently exploring the imagined Gap which is "beyond" the nebulous idea of the "Final Theory". The latter might very well not exist and would in any case be a human artifact formulated in some future extension of human language.

==============================

I find it more interesting to speculate about the existence of aliens. :biggrin:


Could there be other living organisms which have for instance....

...well, might some of them, say, if they exist, have discovered Planck's constant?

Does Planck's constant have a kind of rough approximate cross-cultural universality? In the sense that something like it eventually gets discovered a lot of times by various other forms of life (if there are any.)
Let me get it straight. I'm atheist. I don't believe in God, so don't worry I'm not a loon. Well. I was thinking along the line of Roger Penrose who said the brain processes was noncomputable.. that is.. consciousness is beyond math (and can never be modeled by math). So I wondered what would happen if such mathless mechanism is what is behind QM and GR, then their unification may involve mathless mechanism. Something like that. But you said it's categorically and 100% certain that all can be explained by math, including Penrose idea of brain and consciousness and everything. So I'd believe you in the meantime. But if others here who can think of an exception, then pls. share. Thanks.
 
  • #20
marcus
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you said it's categorically and 100% certain that all can be explained by math, including Penrose idea of brain and consciousness and everything...
Where do you think I said that? Could you quote the exact sentence? I'm curious how you got that idea.

What I thought I said was that math has no fixed essence. It is an evolving growing human language. We cannot know our future, so in particular we cannot know the limits of what can and cannot be described.

I wouldn't be apt to say what you attribute to me because a categorical statement would presume knowledge of the future evolution of the language and what will or will not be expressible/explainable.

My attitude here is skeptical agnostic about capabilities of human language and its symbolic extensions. As I said, I don't think your original question made sense.

Roger Penrose who said the brain processes was noncomputable.. that is.. consciousness is beyond math (and can never be modeled by math)
It does not follow that if some process is noncomputable (say by a Turing machine) it is "beyond math" and cannot be modeled.
Modern math deals with lots of stuff which is technically not computable, say by a finite automaton in a finite time. That's part of the fun, these days.
Indeed quantum mechanics itself models processes which are not deterministic and as far as we know are not computable.

You had better quote the exact words of Penrose. You may be confused about what he's saying, or over-interpreting. Popular books often mislead people.

Or Penrose could have been wrong. Many people think his book about consciousness was below par, not up to his usual standards. I haven't read it. So I would need a quote. Maybe you can find a link to the passage in question in google books.
 
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  • #21
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Where do you think I said that? Could you quote the exact sentence? I'm curious how you got that idea.

What I thought I said was that math has no fixed essence. It is an evolving growing human language. We cannot know our future, so in particular we cannot know the limits of what can and cannot be described.

I wouldn't be apt to say what you attribute to me because a categorical statement would presume knowledge of the future evolution of the language and what will or will not be expressible/explainable.

My attitude here is skeptical agnostic about capabilities of human language and its symbolic extensions. As I said, I don't think your original question made sense.



It does not follow that if some process is noncomputable (say by a Turing machine) it is "beyond math" and cannot be modeled.
Modern math deals with lots of stuff which is technically not computable, say by a finite automaton in a finite time. That's part of the fun, these days.
Indeed quantum mechanics itself models processes which are not deterministic and as far as we know are not computable.

You had better quote the exact words of Penrose. You may be confused about what he's saying, or over-interpreting. Popular books often mislead people.

Or Penrose could have been wrong. Many people think his book about consciousness was below par, not up to his usual standards. I haven't read it. So I would need a quote. Maybe you can find a link to the passage in question in google books.
Ok. I'll look for the Penrose book called "The Emperor's New Mind". It's in one of the big boxes in my attic. I have over one thousand books of all kinds not arranged so I'll look for it tomorrow. Thanks for the emphasis that is' an open question. This means it is within the possibility that quantum gravity or planckian universe is composed of things where causation doesn't exist and indeterministic is many magnitudes worse than QM, and integers and numbers don't even have precedence or logic. But from this emerge quantum mechanics and general relativity because of symmetry breaking of this mathless unreal no ontology beyond the beyond realm of pure chaos.
 
  • #22
marcus
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... indeterministic is many magnitudes worse than QM, and integers and numbers don't even have precedence or logic. But from this emerge quantum mechanics and general relativity because of symmetry breaking of this mathless unreal no ontology beyond the beyond realm of pure chaos.
This sounds like poetry to me. It is an intense vision of fertile illogical turmoil.

If I were you I would simply admit that this is your own vision and stop pretending you can support it with Penrose.

At this point I would say don't bother to look in your attic for Penrose consciousness book.
This is just my two cents worth of advice. Save yourself the trouble. I don't see how there is any chance that Penrose ideas would support such extreme regard for utter chaos.
=================

Lee Smolin, as I recall, or someone in his circle, has toyed with a scheme where both geometry and quantum mechanics arise out of total connectivity (or if you like total chaos) by evolution according to some rules which in effect favor breaking connections and smoothing things out.

QM arises in this scheme from "disordered locality", the residue of connectivity that didnt get smoothed out. QM is explained, in a sense, as a rogue residue in geometry.

I don't advocate this, even in the slightest. I mention it because you keep harping on your idea that both GR and QM arise from a single primordial insanity. Smolin, or one of his friends, realizes a similar idea (using invented symbol-enhanced language, i.e. mathematics, to describe how this kind of thing might happen.)
 
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  • #23
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This sounds like poetry to me. It is an intense vision of fertile illogical turmoil.

If I were you I would simply admit that this is your own vision and stop pretending you can support it with Penrose.

At this point I would say don't bother to look in your attic for Penrose consciousness book.
This is just my two cents worth of advice. Save yourself the trouble. I don't see how there is any chance that Penrose ideas would support such extreme regard for utter chaos.
=================

Lee Smolin, as I recall, or someone in his circle, has toyed with a scheme where both geometry and quantum mechanics arise out of total connectivity (or if you like total chaos) by evolution according to some rules which in effect favor breaking connections and smoothing things out.

QM arises in this scheme from "disordered locality", the residue of connectivity that didnt get smoothed out.
And this can still be modeled by math. Ok. So if we discovered the theory of Quantum Gravity. They say it can tell what happens 1/10^10^100000 seconds after the Big Bang. But I guess quantum gravity won't help us understand what occured prior to the Big Bang, isn't it when you have to admit that math may lose its predictive power or even usages at T=0 when Space, Time and Matter don't even exist.
 
  • #24
marcus
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And this can still be modeled by math. Ok. So if we discovered the theory of Quantum Gravity. They say it can tell what happens 1/10^10^100000 seconds after the Big Bang. But I guess quantum gravity won't help us understand what occured prior to the Big Bang, isn't it when you have to admit that math may lose its predictive power or even usages at T=0 when Space, Time and Matter don't even exist.
QG models already go back before the big bang.
The big issue now is to test the models. If some pass tests they will gain cred and tend to supplant the old GR Singularity "beginning of time and space" idea.

"Breakdown of physical law" is a pre-2005 idea that is still current in popularizations I guess. These days different people have their different models that do not suffer singularity and go back smoothly to conditions before where General Relativity is inapplicable.

Here are some 240 papers of this type of research that have appeared since beginning of 2009. Have a look at some of the titles and some of the abstracts to get an idea.
http://www-library.desy.de/cgi-bin/spiface/find/hep/www?rawcmd=dk+quantum+cosmology+and+date+%3E+2008&FORMAT=WWW&SEQUENCE=citecount%28d%29 [Broken]

isn't it when you have to admit that math may lose...
No. It just means that a particular theory, Gen Rel, is inapplicable at very high density and needs modification.
Nothing so dramatic or grandiose as you imagine---that is just the amplification used to sell popular books and improve pop-sci channel viewer ratings. Trumped-up money-driven distortion.
 
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  • #25
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But I guess quantum gravity won't help us understand what occured prior to the Big Bang, isn't it when you have to admit that math may lose its predictive power or even usages at T=0 when Space, Time and Matter don't even exist.
Big bang was thirteen point eight billion light years ago relative to our now, time in the form of duration, space in the form of vacuum between particles, and the particles themselves all appear from this one energetic point. T=0 is using math, T=0 is how we describe all starting points and if you think of this one as the beginning you are thinking in terms of Minkowski space/time a mathematical model. Trying to visualize prior to big bang is not predictive power it is prior conditions.
 

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