String Theory and the Multiverse

[ArnautDaniel]

And string theory was postulated after physicists noticed that quantum mechanics and general relativity are incompatible.

You do understand the difference between a problem arising from issues with empirical measurement, and a problem arising because there are issues with the math.

And incidentally, how do you solve a math problem, by positing a theory that isn't mathematically rigorous or sound?

That's an undeniable problem, one which string theory solves.

On the contrary, a "theory" in which you can't perform a calculation doesn't solve anything.

But, as in our previous conversation, you can show string theory isn't useless crap by showing a calculation that predicts an empirical measurement that it actually gets right.

I see no difference between these two scenarios, other than the fact that string theory is orders of magnitude more difficult.

Again, you seem to have trouble distinguishing symbols on a page from an actual measurement.

 

[Chalnoth]

i find this simplistic, since string theory cannot even be tested. (Actually with our newer particle accelerators it can be but still hasnt proven valid)

As I have said, while the theory as a whole can't be tested, string theory has inspired a great many specific scenarios which can be.

How do you account for the growing number of scientists who scoff at it even being called a 'theory'?

They're a tiny minority and the perception that they are "growing" is false.

How do you account for one of string theories main proponants, Muth, admitting it doesnt even work out?

Who? I hope you're not talking about this guy, because he claims to be a graphic designer, not a theoretical physicist.

It seems to me it takes more faith to give string theory any credence, than it does to believe "God did it"

1. Nobody is yet stating that string theory is actually true.
2. String theory is actually well-defined. God is not.
3. The prediction of quantum gravity alone is strong reason to believe that there is something worth pursuing about string theory.

What do you know of Muth's acertion that string theory can explain the moments before the actual bankg of the big bang?

I have no idea what you're talking about.

 

[Chalnoth]

You do understand the difference between a problem arising from issues with empirical measurement, and a problem arising because there are issues with the math.

A minor and inconsequential difference. Both are ways of showing that the theories we have are definitively incorrect.

And incidentally, how do you solve a math problem, by positing a theory that isn't mathematically rigorous or sound?

Um, because it's a specious accusation?

 

[ArnautDaniel]

A minor and inconsequential difference. Both are ways of showing that the theories we have are definitively incorrect.

It is a huge difference. Theories are based on empirical measurements, empirical measurements aren't based on theories.

Only a third rate theorist would fail to see the difference.

Um, because it's a specious accusation?

Well if you can point to the place where it is demonstrated in rigorous mathematics that string theory is mathematically rigorous and mathematically sound I will admit I'm wrong.

You wont be able to because plain vanilla QFT doesn't even meet those criteria...like I said there is an issue with defining a measure for the path integral...and on top of that there is an outstanding issue with whether quantum fields formulated as path integrals can even be related to quantum fields formulated in an operator formalism.

Of course physicists being physicists will apply results from a path integral quantum field theory to an axiomatic/algebraic quantum field theory and vice versa.

...

Incidently I would expect someone posing as some kind of expert to be able to demonstrate some depth of understanding....

 

[Chalnoth]

It is a huge difference. Theories are based on empirical measurements, empirical measurements aren't based on theories.

Only a third rate theorist would fail to see the difference.

Um, let's see.

Case 1: Theory doesn't match with observation -> theory must be wrong.
Case 2: Theory doesn't match with other experimentally-verified theory -> theory must be wrong.

Nope. I don't see a difference. None that matters at any rate. Are you seriously arguing that there is no need to reconcile quantum mechanics and general relativity?

 

[WolfBitnGodSmittn]

Um, let's see.

Case 1: Theory doesn't match with observation -> theory must be wrong.
Case 2: Theory doesn't match with other experimentally-verified theory -> theory must be wrong.

Nope. I don't see a difference. None that matters at any rate. Are you seriously arguing that there is no need to reconcile quantum mechanics and general relativity?

ive got to say i find you grasping air with string theory, and you dont seem to be familliar with Muth. If youre interested i can get you info on him and some of his own negative observations

Be that as it may, there are things you and i agree on, for instance the need to reconcile quantum mechanics with relativity.

Actually this is a fairly easy concept to grasp, though a bit hard to understand without 'pictohelp' which i suck at

If youd be interested in discussing this reconciliation just let me know... its actually quite a simple concept

 

[plindboe]

ive got to say i find you grasping air with string theory, and you dont seem to be familliar with Muth. If youre interested i can get you info on him and some of his own negative observations

No Muth-written string theory papers on Google Scholar.
Few results on Google, different people named Muth.

Obviously, you either mispelled his name or your claim that this is one of string theory's main proponents is false. If even Google has troubles finding the guy, he can't have been of much importance.

Peter

 

[WolfBitnGodSmittn]

LMAO, youre right... Muth was my math Teacher, GUTH is the physicist i'm referring to, Alan Guth.

 

[Chalnoth]

LMAO, youre right... Muth was my math Teacher, GUTH is the physicist i'm referring to, Alan Guth.

Ah, Alan Guth, yes. But I'm not familiar with him from string theory, rather from his work on inflation.

As far as string theory, I think it's got some very appealing aspects, but it needs lots of work. What you can expect to see as physics move forward is that as the LHC turns on and starts producing results, theorists will shift away from string theory and focus on more directly-testable scenarios. Presumably new things will be discovered there that will provide us with new directions of investigation. And presumably those avenues will dry up after a decade or so.

Unless we are inspired by the LHC results to discover some other, alternative potential theory of everything, then string theory work will once again pick up when the results out of the LHC slow down. It's not clear at present just how much it will take to fully develop string theory (which presently means fully developing M-theory), but it does seem that it will take very many man-hours to flesh it out.

 

[WolfBitnGodSmittn]

Chalnoth, correct me if im wrong, but wasnt the theory supposed to have been tested with the completion of the Hadron collider?

I know there were a lot of hopeful people. Every time i spoke of the sinking ship of string theory and how it was untestable, the return responce was that it would be tested with the completion of the super collider.

Ive heard it WAS to be done but never heard that it HAD

 

[Chalnoth]

Chalnoth, correct me if im wrong, but wasnt the theory supposed to have been tested with the completion of the Hadron collider?

What? No. As far as I know, nobody was expecting any of the sort. Now, there are a few rather speculative scenarios inspired by string theory that can be tested at the LHC. But this is somewhat different from testing string theory.

I know there were a lot of hopeful people. Every time i spoke of the sinking ship of string theory and how it was untestable, the return responce was that it would be tested with the completion of the super collider.

Either you misunderstood them, or they were off their rocker.