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Michael Noonan
2007-Oct-14, 12:25 PM
I am guessing it would answer a few questions but would anyone actually recognise it if it did exist?

Michael Noonan
2007-Oct-14, 01:04 PM
Perhaps I had better expand that a bit:-
Would it need to look like all the theories
General Relativity
Quantum Mechanics
Electric or Plasma Universe
String Theory

Would it be so bad if it looked like the Flying Spaghetti Monster?

Kaptain K
2007-Oct-14, 01:56 PM
Just like relativity did not make Newtonian physics wrong, but merely placed limits on where it was viable, a unified theory would not make current physics obsolete, but it would put constraints on where it would be used.

Michael Noonan
2007-Oct-14, 02:09 PM
Just like relativity did not make Newtonian physics wrong, but merely placed limits on where it was viable, a unified theory would not make current physics obsolete, but it would put constraints on where it would be used.

So would it need to explain the expanding universe or would it be enough if it just said the universe looked like it was expanding?

Physics would still have to work naturally but surely a Unified Theory should look like everything from string onwards no matter how strange it appeared.

It should even be able to explain polhode motions unless there is already an explanation for them.

01101001
2007-Oct-14, 04:01 PM
What would Unified Theory mean?

I am guessing it would answer a few questions but would anyone actually recognise it if it did exist?

Small, Medium, Large, or X-Large?

I hope it would mean a cool new geeky T-shirt, an equation or two that sums up the Theory of Everything.

Anyone would recognize it by the caption on the shirt: "Theory of Everything".

Physicist Leon Lederman (http://en.wikiquote.org/wiki/Leon_M._Lederman): "My ambition is to live to see all of physics reduced to a formula so elegant and simple that it will fit easily on the front of a T-shirt."

Michael Noonan
2007-Oct-14, 04:16 PM
Small, Medium, Large, or X-Large?

I hope it would mean a cool new geeky T-shirt, an equation or two that sums up the Theory of Everything.

Anyone would recognize it by the caption on the shirt: "Theory of Everything".

Physicist Leon Lederman (http://en.wikiquote.org/wiki/Leon_M._Lederman): "My ambition is to live to see all of physics reduced to a formula so elegant and simple that it will fit easily on the front of a T-shirt."

I hope the T-shirt would fit a variable body although I would still be an XX-large. I thought Unified Theory was just the physics and that the Theory of Everything would encapsulate thought and metaphysics.

Tim Thompson
2007-Oct-14, 04:55 PM
I thought Unified Theory was just the physics and that the Theory of Everything would encapsulate thought and metaphysics.
The "theory of everything", as it is used by physicists, is limited to physics. It amounts to a single set of equations which are together sufficient to explain all of physics. There already is such a set to simultaenously explain electromagnetism, the weak force & the strong force (the theory is called quantum chromodynamics (http://en.wikipedia.org/wiki/Quantum_chromodynamics), and is the basis for the Standard Model (http://en.wikipedia.org/wiki/Standard_Model) of particle physics). But gravity is left out. Certainly, such a theory would be recognized, if we found it. But there is no real guarantee that such a theory exists. After all, in general relativity, there is no "force" of gravity at all. You can't unify the four forces, if in fact there are only three.

hhEb09'1
2007-Oct-14, 05:28 PM
Would it be so bad if it looked like the Flying Spaghetti Monster?Only if it were driving a tractor :)

Just think about one of the times that this sort of thing happened before. The theory of relativity integrated a lot of diverse theories. As Tim says, general relativity may be outside of the realm of the other forces--but those other forces form (theory) has been modified by relativity, especially special relativity but that's just a form of general relativity, right? :)

01101001
2007-Oct-14, 06:19 PM
I thought Unified Theory was just the physics and that the Theory of Everything would encapsulate thought and metaphysics.

Wikipedia: Theory of Everything (http://en.wikipedia.org/wiki/Theory_of_everything)



A theory of everything (ToE) is a hypothetical theory of theoretical physics that fully explains and links together all known physical phenomena. [...]
In current mainstream physics, a Theory of Everything would unify all the fundamental interactions of nature, which are usually considered to be four in number: gravity, the strong nuclear force, the weak nuclear force, and the electromagnetic force. Because the weak force can transform elementary particles from one kind into another, the TOE should yield a deep understanding of the various different kinds of particles as well as the different forces.

Metaphysics? A scientific theory to explain metaphysics?

Moonhead
2007-Oct-14, 07:09 PM
Would such a theory -if this question is answerable at all- be of help with e.g. cold nuclear fusion, or even, more speculative, help scientists to create wormholes and/or quantum foam, exotic matter etc.? Or would that still be a few steps ahead? (or, totally unrelated?)

sunspot
2007-Oct-18, 09:54 PM
I hope this thread continues, since I just joined BAUT because this is really an interesting question to me.

It seems that a <comprehensive>, mathematical TOE can only be recognized if it allows the derivation of the results of <all possible> scientific observations from physics to biology to social behavior, and on all scales from Planck (and lower ?) to the multiverse (and higher?). While this "all possible" phrase makes it clearly impossible to verify/recognize a <comprehensive> TOE, (see Karl Popper), it seems like we still can verify/recognize a "limited" TOE if we replace the "all possible" phrase with "all current". This way our computational power should not be a factor, since the theory should implicate (not predict!) future observations as our compute power improves.

However, there's a basic mathematical issue, even with a limited TOE: we probably won't be able to understand the equations! For example, if God revealed Maxwell's equations to a prophet, the writing would have been ignored by the people of the bible as unintelligible gibberish! Without the context of a paradigm, developed gradually within a scientific/social setting of metaphors and analogies, we need a scientist "prophet" to explain the meaning of the TOE. And this prophet's explanations would probably be dismissed as unintelligible gibberish for any sufficiently advanced theory, even today.

For example, General Relativity and "curved space-time" was nearly unintelligible. Without Eddington's data, the concepts may have languished. And Quantum Mechanics still lacks any analogy to "normal" metaphors; we're still using crutch terms like "particle" to describe an entity that has no "surface".

Bottom line: I see a TOE as a myth that excites the imagination, but seems highly impractical, if not totally impossible. Hopefully, this may inspire someone to prove me wrong! But don't be discouraged if no one understands you, and calls you a nut case.

Michael Noonan
2007-Oct-19, 04:26 AM
I hope this thread continues, since I just joined BAUT because this is really an interesting question to me.
(snip)
Bottom line: I see a TOE as a myth that excites the imagination, but seems highly impractical, if not totally impossible. Hopefully, this may inspire someone to prove me wrong! But don't be discouraged if no one understands you, and calls you a nut case.

I am glad you like the question. There have been a number of very good answers and no I am definitely not discouraged. I can't vouch for the real scientists though.

Laguna
2007-Oct-19, 09:52 AM
As far as my physics professor once mentioned to us, to reach a TOE and test it, you would need to perform experiments that would include everything in the universe (as you would need to include gravity).

Tim Thompson
2007-Oct-19, 03:45 PM
I think that "Theory of Everything" are words chosen more for their subjective impact than their objective strength, at least from any practical point of view. Physicists classically view the universe in terms of four fundamental forces (http://hyperphysics.phy-astr.gsu.edu/hbase/forces/funfor.html):

Strong force (http://en.wikipedia.org/wiki/Strong_interaction)
Weak force (http://en.wikipedia.org/wiki/Weak_interaction)
Electromagnetism (http://en.wikipedia.org/wiki/Electromagnetism)
Gravity (http://en.wikipedia.org/wiki/Gravity)

Each of these forces is described by its own, unique basic set of equations which describe how they work. Scientists have discovered that by adding additional parameters that can create new basic sets of equations which include more than one of these forces. Indeed, at this point, scientists have established what is called electroweak unification (http://en.wikipedia.org/wiki/Electro-weak), which provides a basic set of equations which simultaneously describe the workings of the 2nd & 3rd forces combined, and quantum chromodynamics (http://en.wikipedia.org/wiki/Quantum_chromodynamics), which describes the simultaneous combination of the first 3 forces.

One of the problems that this solution creates is that we see the first 3 forces as being unique. We do not see in practice that they are the same. So we have to come up with a way to allow the forces to "be the same" during the early infancy of the evolving universe, and then at some point achieve their separate identities. It's like watching identical twins grow up into not so twin personalities. The current favorite idea is to invoke phase transitions (http://en.wikipedia.org/wiki/Phase_transition) in the evolving universe, each of which is an event that separates out one of the forces.

Another problem is that the 3 united forces are easily understood as "forces" both classically, and in quantum mechanics. Each force is mediated by the exchange of a virtual particle (http://en.wikipedia.org/wiki/Virtual_particle) that allows real particles to feel a force. That's the trick behind quantum mechanical forces. But gravity has gone its own way, via Albert Einstein (http://en.wikipedia.org/wiki/Albert_Einstein), to become an exercise in geometry (http://en.wikipedia.org/wiki/Geometry). That which we experience as the "force" of gravity is not properly a "force" at all, so that in general relativity (http://en.wikipedia.org/wiki/General_relativity) there is no "force" of gravity. Rather, gravity is simply a manifestation of a curved surface, in this case, curved spacetime. How does one "unify" 4 forces, if there are really ony 3?

There is a strong bias in the theoretical physics community in favor of the notion that gravity must be just as much a "force" as the other 3. It is not known that this must be true, but we assume it is anyway, and go off in serach of ways to make it so. The first 3 forces were always understood in what has turned out to be "quantum friendly" form. Gravity (http://www-history.mcs.st-and.ac.uk/HistTopics/Gravitation.html) has not, and that's the major hang-up at the moment. How do we rebuild a theory of gravity in a "quantum friendly" form? String theory (http://en.wikipedia.org/wiki/String_theory) is one attempt, loop quantum gravity (http://en.wikipedia.org/wiki/Loop_quantum_gravity) is another. Those two are probably the most popular quantum gravity (http://en.wikipedia.org/wiki/Quantum_gravity) theories at the moment.

The motivation here is that, in principle, everything that happens in physics (http://scienceworld.wolfram.com/physics/) can be ultimately described in terms of the 4 fundamental forces. If those 4 forces can be "unified" in one master set of basic equations, they become is a sense "one force" instead of "four forces", and that master set of basic equations becomes a "Theory of Everything". It is an almost metaphysical achievement. After all, if you want to calculate the temperature of a candle flame, you are unlikely to start your computations with the master set of equations from the Theory of Everything. There are far more practical ways to handle the problem. So we need to realize that the practical implications of any ToE are somewhere between slim and none. But the philosophical implications are much greater because a successful ToE will deceive us into thinking we really understand the universe at last.

P.S. - A note on Wikipedia (http://wikipedia.org/).
I make extensive use of links to Wikipedia, despite the fact that anybody can edit the articles. I find this has no effect on uncontroversial topics, and that Wikipedia is an excellent place to start most of the time. I like the layout, and I like the "portal" nature of the pages, which often provide extensive outside links for further reading/study, if you are so inclined. But of course no webpage(s) can ever substitute for the "real thing", textbooks and classes.

Michael Noonan
2007-Oct-19, 05:38 PM
I think that "Theory of Everything" are words chosen more for their subjective impact than their objective strength, at least from any practical point of view.
(snip)
P.S. - A note on Wikipedia (http://wikipedia.org/).
I make extensive use of links to Wikipedia, despite the fact that anybody can edit the articles. I find this has no effect on uncontroversial topics, and that Wikipedia is an excellent place to start most of the time. I like the layout, and I like the "portal" nature of the pages, which often provide extensive outside links for further reading/study, if you are so inclined. But of course no webpage(s) can ever substitute for the "real thing", textbooks and classes.

Thank you Tim Thompson,
I am a visual person and found the look of this (http://imgsrc.hubblesite.org/hu/db/2007/01/images/a/formats/web_print.jpg) geometry and this (http://en.wikipedia.org/wiki/Calabi%E2%80%93Yau_manifold) geometry remarkably similar.

Now the first is 83kb jpeg from Hubble and is the mapping of density in space.
The second is the Wiki entry for Calabi-Yau manifolds for quantum theory.

I find Wiki most helpful and wondered if anyone else noticed just how remarkably alike the big picture and the little picture are?

alainprice
2007-Oct-19, 05:44 PM
I'm just thinking out loud here, but is there a conservation in gravity that might indicate an underlying symmetry?

Michael Noonan
2007-Oct-20, 11:01 AM
I'm just thinking out loud here, but is there a conservation in gravity that might indicate an underlying symmetry?

Hello alainprice,
It is just that I noticed that there are some similarities in the fairly simple shape of space in the larger billions of years view of the universe and in the Calabi-Yau shape the mathematicians use in string and super-string ideas.

As for conservation in gravity that could require a different approach to what we think of as gravity. Twistor theory by Sir Roger Penrose uses a 4D approach and that is complex, to use 6D would change other parts as well.

I can't say more than that I found similarities in a shape that is a useful mathematical construct as I would be breaking forum rules and I don't wish to do that. As a hobby I play with ideas on gravity and shape but don't seem to be getting very far.

Cougar
2007-Oct-21, 03:37 PM
It is just that I noticed that there are some similarities in the fairly simple shape of space in the larger billions of years view of the universe and in the Calabi-Yau shape the mathematicians use in string and super-string ideas.
Well, the first linked jpg shows the evolution of the distribution of dark matter in a particular region of space; it is not the "shape of space." And I believe any similarities in that graphic rendition and the interesting rendition of a Calabi-Yau manifold is purely coincidence. I think if you look at the Calabi-Yau manifold (http://en.wikipedia.org/wiki/Image:Calabi-Yau-alternate.png) more closely, you'll find there aren't really that many similarities.

mugaliens
2007-Oct-21, 05:10 PM
Anyone would recognize it by the caption on the shirt: "Theory of Everything".

Ouch! My TOE (http://en.wikipedia.org/wiki/Grand_unified_theory)hurts.

I suppose we'll find out when we get to 10^16 GeV.

trinitree88
2007-Oct-22, 05:48 PM
Ouch! My TOE (http://en.wikipedia.org/wiki/Grand_unified_theory)hurts.

I suppose we'll find out when we get to 10^16 GeV.

Mugs...When your TOE hurts............................................. .................................................. ........................call a tow truck.:shifty: pete

Michael Noonan
2007-Oct-23, 03:33 PM
The concept of a unified theory would need to explain symmetry.

Is there symmetry in the ratio of Planck size to the diameter of a proton
similar to the diameter of a proton to the estimated size of the universe?

mugaliens
2007-Oct-23, 04:04 PM
Mugs...When your TOE hurts............................................. .................................................. ........................call a tow truck.:shifty: pete

:lol:

You're funny, Pete. Can't spell worth a dang, but you're still funny. At least you made my last few minutes!

See you around the boards.

- Mugs

mugaliens
2007-Oct-24, 05:58 AM
The concept of a unified theory would need to explain symmetry.

Is there symmetry in the ratio of Planck size to the diameter of a proton
similar to the diameter of a proton to the estimated size of the universe?

[breaking out the calculator...]

Ratio - PC to Proton 2.49019E+16
Ratio - Universe to Proton 4.72727E+25

No. Not even close by more than 9 orders of magnitude.

Michael Noonan
2007-Oct-24, 01:29 PM
[breaking out the calculator...]

Ratio - PC to Proton 2.49019E+16
Ratio - Universe to Proton 4.72727E+25

No. Not even close by more than 9 orders of magnitude.

Thank you mugaliens
I remember the old creationist chart in my school that had 1 metre as the centre and everything revolving around the scale of humanity. I had wondered if science taught as science had changed the boundary of symmetry.

Cheers