The theory of everything

  • #1

Main Question or Discussion Point

if leptons and quarks are indeed the ultimate constituents of matter,,
as physicists today tend to believe,we should be able to construct a final theory of the structure of matter,just as Einstein dreamed to doing.
this theory whimsically called the theory of everything. it is a combination of the standard model and a quantum theory of gravity

want to hear your opinions on this theory ?
 

Answers and Replies

  • #2
ZapperZ
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You might want to read this first:

http://www.pnas.org/content/97/1/28.full.pdf

In other words, condensed matter physicists in general do not think that there is such a thing as a "Theory of Everything". And considering that condensed matter is the largest branch of any professional physics society, you can draw your own conclusion from that.

Zz.
 
  • #3
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I much prefer the Theory of Nothing. That nothing is made of quarks and we're just products of some virtual reality.
 
  • #4
SixNein
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if leptons and quarks are indeed the ultimate constituents of matter,,
as physicists today tend to believe,we should be able to construct a final theory of the structure of matter,just as Einstein dreamed to doing.
this theory whimsically called the theory of everything. it is a combination of the standard model and a quantum theory of gravity

want to hear your opinions on this theory ?
The reason it cannot happen is due to the incompleteness theorem.

http://en.wikipedia.org/wiki/Theory...ence_to_G.C3.B6del.27s_incompleteness_theorem

Some people want to believe that models will be the answer, but I'm afraid their going to be disappointed.
 
  • #5
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SixNein, you are a one trick pony. Did you just learn about the incompleteness theorem and now think you should apply it to every question possible? it's annoying.

I just don't get it, even if we can't answer everyone question that doesn't change how we should act, we should still do research and see what happens. I don't see the use of these theorems.
 
  • #6
SixNein
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SixNein, you are a one trick pony. Did you just learn about the incompleteness theorem and now think you should apply it to every question possible? it's annoying.

I just don't get it, even if we can't answer everyone question that doesn't change how we should act, we should still do research and see what happens. I don't see the use of these theorems.
ROTF You guys keep touching upon it, I can't help it. You know 99.9% of the population cannot name 1 mathematical theorem? Besides it's not like I didn't provide a link with a direct quote from one of the most famous physicist alive. If you cannot trust hawking man who can you trust?
 
  • #7
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ROTF You guys keep touching upon it, I can't help it. You know 99.9% of the population cannot name 1 mathematical theorem? Besides it's not like I didn't provide a link with a direct quote from one of the most famous physicist alive. If you cannot trust hawking man who can you trust?
There are other physicists just as accomplished as Hawking who do not believe it. Some mathematicians who work in the field would not like the idea that it can be applied to such usasge.
 
  • #8
DaveC426913
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You might want to read this first:

http://www.pnas.org/content/97/1/28.full.pdf

In other words, condensed matter physicists in general do not think that there is such a thing as a "Theory of Everything".
I thought that the ToE was simply a model that would combine the 4 fundamental forces into one consistent model. Sure, the ramifications are that this would put us on the path to a model of everything that ever was, is, or will be - but that seems to be a separate issue as far as I see it.

Claiming that we cannot create a model of the entire universe from beginning to end is not the same as claiming we can never unite the 4 forces. (IMO)

(It is also my understanding that the title ToE is a misnomer of sorts. Just like GUT is not really all that grand or unified in that it only covers 3 of the 4 forces, so too ToE does not really cover everything.)
 
  • #9
DaveC426913
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You might want to read this first:

http://www.pnas.org/content/97/1/28.full.pdf

In other words, condensed matter physicists in general do not think that there is such a thing as a "Theory of Everything". And considering that condensed matter is the largest branch of any professional physics society, you can draw your own conclusion from that.

Zz.
Actually, a better summation of that article is:

Condensed matter physicsts think that the ToE will be really, really hard to use. Example: because we are starting from first principles, it will tell us little about how proteins fold without vast calculations exceeding our ability.

Well duh.


Having the theory is not the same as applying the theory.
 
  • #10
SixNein
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There are other physicists just as accomplished as Hawking who do not believe it. Some mathematicians who work in the field would not like the idea that it can be applied to such usasge.
Some mathematicians, who work in the field, wish they could sweep the entire thing under the rug. It's like the last stand of classical ideology. Godel himself had trouble accepting the implications of his own theorem. He looked for a way out until the day he died.

http://www.damtp.cam.ac.uk/strings02/dirac/hawking/
 
  • #11
ZapperZ
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Actually, a better summation of that article is:

Condensed matter physicsts think that the ToE will be really, really hard to use. Example: because we are starting from first principles, it will tell us little about how proteins fold without vast calculations exceeding our ability.

Well duh.


Having the theory is not the same as applying the theory.
No, it is not just "applying it". Besides, Laughlin and Pines are not really THAT dumb to not know the difference.

Phil Anderson's "More is Different" also states the same thing. Even if you know all the basic interactions at the individual particle level, you cannot predict high-order organizations in which many of our emergent phenomena sit in. That's the major point in both of these articles. You cannot derive such collective phenomena out of such interactions.

Zz.
 
  • #13
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A theory of almost everything does look attainable. Besides, if a full TOE is achieved and all interactions and correlations in the universe are described mathematically, what would hardcore atheists say about this puzzling notion? Shouldn't a full TOE explain emergent properties and the mystery surrounding the origin of the universe?

EDIT: IMO a full TOE is utterly impossible. Not by a human brain, or at least it's way way too early to even begin to dream about it. How could a human mind comprehend how a whole galaxy can be squeezed to the size of an atom or even zero by a giant blackhole? Aren't we pushing human logic way past its usable limits?
 
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  • #14
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Blenton said:
I much prefer the Theory of Nothing. That nothing is made of quarks and we're just products of some virtual reality.


We should get cheat codes from time to time. It's unfair all this incredible human drama and no cheats.
 
  • #15
SixNein
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Max Tegmark not only believes there is an ultimate TOE, but he even believes the equations of TOE are quite simple
http://arxiv.org/abs/0704.0646
well the problem I have with his hypothesis is this:

I hypothesize that only computable and decidable (in Godel's sense) structures exist
Because then you have to take a look at Cantor and his hypothesis which has pretty much been shown to be impossible to solve. There isn't a consensus, but even the worse renegade would have to say it's a strong argument.
 
  • #16
SixNein
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We should get cheat codes from time to time. It's unfair all this incredible human drama and no cheats.
If you discover the cheat code for money, send it my way =P
 
  • #17
apeiron
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That's the major point in both of these articles. You cannot derive such collective phenomena out of such interactions.Zz.
Another way of putting it is that you need a theory large enough to account for both upward causation and downward causation. So both how things are constructed from "fundamental" components and how things are constrained by global contexts.

The greeks said the same thing - you need both substance and form (both the local components and the global organisation). Holism and systems science tried to get somewhere with this larger view in the last century.

So as the condensed matter guys point out, physics is unbalanced in believing that everything may be explained from the one side of the story. Fundamental physics can only deliver half of everything.

The TO.5E! :smile:

As well as a theory of substance, we need a theory of form.
 
  • #18
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We still are very far away from knowing why we perceive reality the way we do. Any physicist will tell you that reality/the world/ as we perceive it, only exists in our heads. The basic essense of the existence of universe, whether you believe there is an outside world or not, is much different than what our coarse classical human bodies and senses tell us. Why we get such a distorted but beautiful and highly ordered picture of what we term "the universe" is a very deep philosophical question. Suffice to say that a lot of modern physicists appear to be having second thoughts on the 'naturalness' of nature. A simple unification of all the known forces under one theory looks very attainable.

On the other hand, if classical behaviour(e.g. Newton's laws of motion) is an emergent property of large enough quantum systems, the prospects of us finding a TOE would look rather grim.
 
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  • #19
apeiron
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I think it is too pessimistic to say we don't now know a heck of a lot about how the human mind models the world, and about modelling relationships in general. The level of discussion is unsophisticated within the physics commununity, for sure, but it is sophisticated in other communities, particular theoretical biology.

And a decoherence approach to QM would give the kind of top down plus bottom up combined perspective that would make sense. That would not seem mysterious.
 
  • #20
DaveC426913
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I think it is too pessimistic to say we don't now know a heck of a lot about how the human mind models the world...
I don't think we're talking about the mere mental perception of the world; I think we're talking about much more fundamental experiences, such as why organisms (and not just human ones) experience space-time as three dimensions moving within a fourth etc.
 
  • #21
SixNein
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I don't know how you guys can hope for a TOE with the incompleteness proof staring you in the face. It's more or less pretending that it's still possible when it clearly isn't.
 
  • #22
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SixNein, why do you think that Goedels theorem is applicable to physics?
Goedel theorem is applicable to only axiomatic models which are powerful enough to Peano axiomatic. It is not applicable, for example, to geometry (even geometry contains 'numbers' as coordinates, you can not derive Peno there explicitly)

But lets assume that it is applicable to physics. I dont see any problems with it. There some undecidable statements about natural numbers, does it mean that we dont have a number theory? No of course. So we can have axioms (TOE) even if they are incomplete.

In fact, the incompletiness would also affect the hypotetical 'pure-Newtonian' world, where the classical mechanics rule. If you manage to build Turing machine there (it must be complex enough to be self-extendable to be infinite) then you face the same incompletiness problems.
 
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  • #23
SixNein
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SixNein, why do you think that Goedels theorem is applicable to physics?
Goedel theorem is applicable to only axiomatic models which are powerful enough to Peano axiomatic. It is not applicable, for example, to geometry (even geometry contains 'numbers' as coordinates, you can not derive Peno there explicitly)

But lets assume that it is applicable to physics. I dont see any problems with it. There some undecidable statements about natural numbers, does it mean that we dont have a number theory? No of course. So we can have axioms (TOE) even if they are incomplete.

In fact, the incompletiness would also affect the hypotetical 'pure-Newtonian' world, where the classical mechanics rule. If you manage to build Turing machine there (it must be complex enough to be self-extendable to be infinite) then you face the same incompletiness problems.
Physical theories are mathematical models, so Godels theorem applies. A theory of everything would be inconsistent. This means that a theory could not cover everything, which is the purpose of a TOE, and be correct. So physics will always be incomplete, just like mathematics.

Personally, I think its a great thing. There will always be new discoveries and new things to explore.
 
  • #24
Tom Mattson
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Physical theories are mathematical models, so Godels theorem applies.
I think you misunderstand both Goedel's theorem or theoretical physics. As I said in the "origin of the universe" thread, physical propositions are decided empirically, not formally.
 
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  • #25
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Physical theories are mathematical models, so Godels theorem applies.
There are many mathematical models which are Godel-free, where it is not applicable - surprise, surprise!
 

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