# BenTheMan

Senior Members

456

1. ## Bascule, Phil, and Yourdad won! Longshot guess proved right.

Why don't you include the numbers from The Secret'' to improve your averages?
2. ## Bascule, Phil, and Yourdad won! Longshot guess proved right.

Amazon.com sales rank (current) Lee Smolin #562 The Secret #17. http://www.amazon.com/gp/product/1582701709/ref=s9_asin_image_1/104-3907410-9272714?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=center-1&pf_rd_r=136Z2PTFBRPXSFVAXPPX&pf_rd_t=101&pf_rd_p=278240701&pf_rd_i=507846 One can prove what they like when they invent the statistics.
3. ## Time.

This statement is patently false. Gravity and electromagnetism have NOTHING to do with each other, other than that they're forces. IF you want, I can show you how Kaluza and Klein tried to GET electromagnetism from gravity (in 1929), and I can show you why they failed.

That's what I was asking. Presumably people are trying to support intelligent design'' using some example from physics---specifically (I think) Lorentz Ether Theory and Special Relativity. The comparisson is wrong on several levels, but mostly because of General Relativity. Special relativity is what you get when you do general relativity without acceleration---if general relativity is the first principle, then special relativity is a consequence. This is not true about Lorentz Ether Theory---one cannot derive LET from GR. IF that is the claim, then I would be very interested to see the derivation. So, I'm still confused.

Lucaspa---This is not correct. SR doesn't know about gravity, only GR does. All of the calculations done in special relativity are done at a constant acceleration. General relativity gives you the ability to do calculations with acceleration, and (therefore) in a gravitational field. In the absence of any distiguishing characteristics, we select a theory based on how simple it is. The example that jumps to mind is some calculations I did for a Relativistic Quantum Mechanics class when I was getting my master's degree... The calculations were very difficult, and I couldn't figure out how to do them. I found out that using quantum field theory, the calculations were MUCH easier. So I taught myself enough QFT to do the calculations, and received only half credit on the exercizes, because I missed the point''. The thing is, no one used relativistic quantum mechanics if they can help it, even though it gives the same answer. Everybody knows how to use QFT, so that's how we do it. And I object to calling the Feynman sum over paths inelegant. Which path does the electron take? ALL paths, of course! Aside from this, maybe someone can catch me up, without having to read 5 pages of prose...Why are we talking about phsyics here? Presumably, someone brought up the point of competing theories, and used an example from physics? What I don't understand is why I see talk of ethers, which were disproved 100 years ago... The only types of ethers which are allowed are the types with no reference frame. Which means you can't detect them. This is a bit like saying that evolution is driven by an intelligent designer, you just can't detect her.
6. ## Charged leptons don't mix. Why?

Now I have fully convinced myself that I was wrong. If it was truly the case that the mixing was supressed by the large mass differences, then the quarks wouldn't mix. But they do. So I was wrong.
7. ## No Theory of Everything

Man that would be one hell of a lagrangian to write down...
8. ## Do you have a new theory?

Skeptik--- I don't think anyone would object to you phrasing your new theories as questions, i.e. Has anyone ever thought about this?'' Generally I can find something wrong with a new theory'' in the first three scentences of a four page post, and people generally don't really like to hear the reason that they're wrong comes from the first paragraph of their tretise...
9. ## Do you have a new theory?

Wow Severian---I think you just got put in your place.
10. ## No Theory of Everything

I think he's refering to some earlier conversation, where I was talking about effective field theories.
11. ## No Theory of Everything

Everything'' is generally a way to understand to mean gravity + quantum mechanics. (bombus forgets that Einstein stopped doing physics in 1930, and that there are two additional forces that he left out.) As somone pointed out earlier, everything'' is kind of a grandiose word, and it isn't expected that we can derive, say, feminism from string theory.
12. ## Answer your string questions for a nickle! II (string physics only!!!)

Severian--- Two things. I am pretty sure that I can build your model with a heterotic string compactification, and it will be one of the first things I try to do when I finish working on this stupid gauge coupling unification thing I'm doing now. (See below.) The reason it's not so hard is that the 27 of E6 is almost trivial to get out. In general, however, one will have exotic matter, which can generally be given masses near the string scale, decoupling it from the low energy theory. The challenge will be to find just the right conditions so that one gets the right number of 27's, while everything else pairs up into vector-like singlets. This leads me to 2. There are certain things that are VERY difficult to get from string theory, for example, gauge coupling unification in heterotic string models. There is always a problem fitting the low energy data, and one typically has to rely on large threshold corrections, or magic at the GUT/string scale. This is what I am calculating right now, and it is a pain in the ass---i.e. not so easy. In string theory the situation is much more tightly constrained. Since we're deriving everything from (essentially) first principles, the spectrum and such are much more difficult to get right.
13. ## No Theory of Everything

Snail--- I disagree, but it is all semantic. Generally theory of everything'' is just a theory of quantum gravity. Personally I think it's a question of energy scales. If we are somehow able to probe very high energiew, then we should be able to TEST quantum gravity, and we have a very good record of understanding things that we can test. It could be that we start testing the Planck scale at the LHC, in which case we will see a theory of everything within our lifetimes. And Severian and Snail are right, too. If, for example, string theory turns out to be right, then we have to ask, Why strings?'' We will always be led to the same answer---That's just the way it is.'' (This is why you should never believe anyone who tells you that science disproves God Science just constrains God's parameter space.)
14. ## Charged leptons don't mix. Why?

Ahh right. It's a question between mass eignestates and interaction eigenstates.
15. ## Charged leptons don't mix. Why?

Actually I think it may, because the mixing goes like $e^{-\Delta m^2}$, right? Symmetry argument, probably not, unless you look at putting in a discrete family symmetry or something. That's my guess, but I'll keep thinking about it.
16. ## Charged leptons don't mix. Why?

Well, on first thought, the tau is significantly more massive than the muon, which is significantly more massive than the electron. This means that they all decay (via weak interractions) to less massive leptons. So my first guess is that the mass hierarchy (1:10^-3:10^-5) prevents the leptons from mixing. My first guesses are typically wrong, so I'll keep thinking Does anyone agree? OR am I copletely wrong?
17. ## Looking for science authors/writers/experts: debunk pseudoscience!

Ahh. Yes. How cute.
18. ## Looking for science authors/writers/experts: debunk pseudoscience!

I sent an email to staffATdebunked, and it got bounced. Did I screw something up?
19. ## Looking for science authors/writers/experts: debunk pseudoscience!

How detailed of a CV are you looking for?
20. ## Why Most Published Research Findings are False

I think that there has been a recent law in America, addressing the issue. The LEAST suspect are in the theoretical science, like math and physics. Sometimes the application to reality may be suspect, but always one can check calculations for consistency. If you don't believe me that this actually happens, go to arxiv.org and look for papers that start with Reply to...''. These are papers where people point out other's mistakes---usually it boild down to some disagreement over assumptions, otherwise the replies are not so public (generally handled via personal communication). But the problem still remains---much of the computer code that physicsts use is closed source, so there is no real external peer review. One usually counts on academic integrity, and the fact that others do the same problem in a different way, getting similar results.
21. ## Answer your string questions for a nickle! II (string physics only!!!)

Fair enough, but it IS a statement:) The paper you linked to looked interesting (by Stephen King). I only skimmed over the text, but it looks like they fit everything into 27's with a higgs 27+b27? What is the spectrum, exactly? Getting it from a heterotic string compactification might be pretty easy, if it hasn't already been done. PM me and I can send you some references, if you're interested.
22. ## Answer your string questions for a nickle! II (string physics only!!!)

No no. E6 is easy to get---there is a good embedding of E6 in E8, as you know, or can look up in Slansky. The E6 model you linke to puts everything in the 27 of E6, and the 27 is easy to get from string theory. (Generation replication happens in a nice way, too!) The problem is that getting SU(5) to work requires a non-minimal higgs sector. This can be seen in fermion mass predictions---the Georgi SU(5) predicts that the electron and tau have the same mass at the electroweak scale, or some similar goofy thing (I can't remember exactly). To fix this, people add new scalars with mass M_GUT in large representations, for example: http://prola.aps.org/abstract/PRD/v26/i1/p312_1 These authors look at adding a 45 of SU(5) or a 45 and a 70, in order to get fermion mass predictions to work out at the weak scale. The point is, such large representations are difficult to get out of strings, and the post doc I work with assures me that theres a proof---it's not QUITE as straightforward as I mentioned earlier, about the branching rules. So the correct statement is that large GUT higgs representations are generally not present in stringy constructions, and if we find something like SUSY SU(5) with many new GUT higgses, it probably doesn't come from string theory. The caveat is, of course, that someone will probably find (or has found) a way to do it, using some clever math.
23. ## Answer your string questions for a nickle! II (string physics only!!!)

Nothing's wrong with the 27. I LOVE the 27. But it doesn't contain a 45 of SU(5). So if the real world IS SUSY SU(5), then it is unlikely (at least from what I know) that it comes from string theory---it's hard to get big higgses like that, if not impossible, at least from standard model building. As with everything though (and as you rightly pointed out), it is hard to make any firm statements.
24. ## Answer your string questions for a nickle! II (string physics only!!!)

How about only 10^500 monkeys? I disagree that string theory can give you anything you want. I'll give you two examples that I am familiar with. In building SU(5) SUSY GUTs, you generally need higgses in the larger than andjoint reps, for example a 45 to get fermion masse right. But in the heterotic string, one cannot get such large reps out, that I know of. So, for example, start with E8 and break to E6, and then to SO(10) and then to SU(5). The only matter at the string scale is the adjoint of E8 which is the 248. Then you can go to Slansky and find $248 \supset 1+ 27 + \overline{27} + 78$ and $27 = 1 + 10 + 16$ $78 = 1 + 45 + 16 + 16$ None of these SO(10) reps contain the 45 of SU(5). The case when starting from SO(32) is the same, I think. This is all in heterotic strings, where the gauge degrees of freedom are internal bosonic modes. In Type IIA, I'm not sure how one can get reps larger than adjoint of SU(N). The (gauge) degrees of freedom there are strings which start on one brane and end on another, so I don't know how a stack of N branes can ever have more than N^2 - 1 degrees of freedom associated with it. This is one of the main reasons that string theory actually offers an improvement over traditional SUSY GUTs---there you can add arbitrary higgs reps untill you get everything to work out right, in the string side you are limited with what you can add. So while there are SPECIFIC string vacua that have features that we want, there is no single string vacuum (yet) that has all of the features we associate with our universe. ============== I just talked with a post doc about the argument I gave above about large GUT reps. For matter which is localized at orbifold fixed points, the argument is a bit more subtle, but I am assured that it still doesn't work (something about higher level Kac-Moody algebras).
25. ## Books on String Theory

Actually, I would reccomend Barton Zwiebach's book A First Course in String Theory''. Well-written, and there are things there that you can't find anywhere else.
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