Locrian
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Nobel in Physics tomorrow (4 Oct) any guesses?
Locrian replied to Martin's topic in Astronomy and Cosmology
Those are not examples of physics nobels -
Nobel in Physics tomorrow (4 Oct) any guesses?
Locrian replied to Martin's topic in Astronomy and Cosmology
I think physics nobel's are always awarded for discoveries for which there has been plenty of time to determine both that they are eventually accepted and influential. Some physics nobels have been awarded for things done decades ago. I can't think of one given for something that was done the prior year - maybe you could give an example. -
Nobel in Physics tomorrow (4 Oct) any guesses?
Locrian replied to Martin's topic in Astronomy and Cosmology
I wish I had posted the first time I believed this. I suppose a lot of people knew it would come eventually, though. -
On your recomendation Martin I ordered The Trouble With Physics yesterday from Amazon.com. I also picked up Not Even Wrong, partly on impulse. Looking forward to reading them. It may take me a bit to get into them though. I'll do my best. By the way, not long ago I finished the book True Genius, The Life and Times of John Bardeen. It was amazing. Just a thought for the future
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The Trouble with Physics is number one on bestseller list
Locrian replied to Martin's topic in Modern and Theoretical Physics
Well how about an update! I would like your opinion on whether I would find this book interesting. I have not thought much of string theory since I looked into it in 2001. Since I don't need any convincing, would the book contain enough new information that I would enjoy it? Thanks in advance -
The Trouble with Physics is number one on bestseller list
Locrian replied to Martin's topic in Modern and Theoretical Physics
I would agree with Luke that ST is certainly being pursued in a historically unusual fashion. Dirac may have liked pretty equations, but his contribution to physics was very much dependant on experimentation that had been done. Quantum mechanics was a science born of experimental data that conflicted with current theories. There is no such example for string theory. General relativity might be one good example of a broad theory being produced before experimental data (of course special relativity would not be). Of course it rested on a single, powerful principle, something that can't be said of string theory, but I agree with you that this demonstrates such a sequence is possible. This still leaves string theory in a historically unusual position. There is no expeirmental data that demands a theory of quantum gravity. There isn't even absolute evidence that such a regime where a theory of quantum gravity is needed even exists, and if it does, it is difficult to imagine a situation in which the theory would be useful. Of course most physicists would prefer to sit around playing with pretty equations, but let's not forget this urge can work both ways. When Pauli started working on the physics of solids he quickly stopped and warned his students against studying the "physics of dirt." I wonder what those students thought when Bardeen later went on to earn two Nobel prizes studying just such physics. -
The Trouble with Physics is number one on bestseller list
Locrian replied to Martin's topic in Modern and Theoretical Physics
I'm not sure I agree with this. The theory is significantly different than it was in the mid-80's, there are those who say it is no longer really a theory of strings, and the predictions of the past did seem to be swept under the rug as time went by. Of course, I guess its a fair question as to whether the word "prediciton" ever applied to anything that came out of the field. Maybe "suggested" is more appropriate? -
Theorists in particle physics have about thirty years of doing a superbly awful job predicting anything anyone measures before it's measured. This problem has seemed to get worse, not better. Whether or not what the LHC is doing is dangerous (certainly not), the fact that some guy somewhere predicted something bad might happen can be ignored, since there is no good reason to think he's anywhere within the realm of reality.
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The Trouble with Physics is number one on bestseller list
Locrian replied to Martin's topic in Modern and Theoretical Physics
Well it should definitely be said here that while Laughlin has contributed a great deal to physics, many of his current views are... unorthodox, at the least. Certainly many other experts in the field disagree with him on that. The problem with HTS may be more than a problem of not having the appropriate mathematics available though. It may be that what we group under one name is actually a huge set of highly variable separate effects many of which are independant of microscopic factors of the system and shielded by quantum protectorates. In such a case we have to ask ourselves whether there is the possibility nature gave us a knot we can't untangle; we may be able to form some predictive ideas, but they won't be generalizable and won't give us any good picture of the underlying physical mechanisms. You are certainly right to say this is pure speculation. It seems, based on history, a poor bet to make that we will uncover a problem we can't solve. And yet, we may have already done so in the past and are just used to the idea. Turbulent fluids comes to mind. This, to me, would be The problem with physics - the identification of a broad problem rooted in experiment we can't solve. In other words, a physical system we can't appropriately describe. To me, quantum gravity doesn't actually meet this criteria as of yet. I think there is another book in all this. -
The Trouble with Physics is number one on bestseller list
Locrian replied to Martin's topic in Modern and Theoretical Physics
I didn't say anything about deciding they were wrong. Please read my post more carefully. -
The Trouble with Physics is number one on bestseller list
Locrian replied to Martin's topic in Modern and Theoretical Physics
This is correct. String theory has made a few vague' date=' general, but useful predictions in the past. The point is they were [i']wrong[/i]. The discovery of a cosmological constant was a huge blow to the field. String theory certainly doesn't make any predictions now in the form(s) that it is. Its continuing failure to reproduce the standard model decades after inception suggests that it suffers from a very serious problem indeed. True, but the physical ones certainly can, which means it is still an interesting subject. As for the Feynman quote, I've heard it too, but as much as I still agree with it, the truth is it was said decades ago and string theory is really an entirely different animal now. -
This is a great point. Also, to me it seems like this algorithm penalizes people responsible enough to cite lots of other people's ideas. But as Martin says, it is just for fun (let's hope). If anyone else has any opinion about whether Anderson is actually a good choice for "most creative" I'd be interested in hearing it.
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The Trouble with Physics is number one on bestseller list
Locrian replied to Martin's topic in Modern and Theoretical Physics
Right, because book reviews can be judged based on wether they contradict the data or not. -
The Trouble with Physics is number one on bestseller list
Locrian replied to Martin's topic in Modern and Theoretical Physics
Can anyone who has read or has a familiarity with the book sum up exactly what The problem with physics is supposed to be, as made in the book? -
The Trouble with Physics is number one on bestseller list
Locrian replied to Martin's topic in Modern and Theoretical Physics
Yea it was my understanding that Severian was reffering to Motl, and that was the subject of my post. Motl was not asked the 2006 edge question. Fair enough, I'll not add to that discussion even if it reappears. -
The Trouble with Physics is number one on bestseller list
Locrian replied to Martin's topic in Modern and Theoretical Physics
More on topic, the thing that annoys me about the book is its title: it should be titled A Trouble in Physics. I'm not aware of any problem that would qualify as being a problem in physics that affected every area of the discipline, and certainly none that have anything to do with HEP. I haven't read the book (and hope not to have to), but the title sure seems to give a very wrong impression. -
The Trouble with Physics is number one on bestseller list
Locrian replied to Martin's topic in Modern and Theoretical Physics
Well, I've never met anyone who actually respected him; I doubt anyone I work around knows anything about him. I'm sure they're out there, but calling him "respected" deserves some sort of context. On the other hand, Motl has a habit of being abusive, insulting, irrational and absurd. I can provide any number of quotes from him made online that consist of nothing more than personal insults with no information, no argument and no intellectual value. Discounting his opinion... hard to say... but if being obnoxious, unprofessional, unproductive and childish isn't reason to ignore someone, what is? -
SciAm reviews QG book (September issue)
Locrian replied to Martin's topic in Modern and Theoretical Physics
I have a question Martin - its one that occurs to me every time I see the title of this book. Does the book actually pose problems for Physics, or does it merely pose problems for some specific area of physics he happens to work in? Because it seems to me that areas like organic electronics, high temperature superconductivity, nanotechnology, lasing, and even cosmology and astrophysics in general, are all areas that continue to do interesting experiments, propose interesting problems and produce interesting theory. Do you know if he actually adresses that? -
Universe Might be Bigger and Older than Expected
Locrian replied to darkangel199's topic in Astronomy and Cosmology
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Universe Might be Bigger and Older than Expected
Locrian replied to darkangel199's topic in Astronomy and Cosmology
Apoligies if I'm going to sound like an Eeyore here, but I think the author of this article does not have things in perspective. 1) 16 billion and 14 billion are pretty close. It was only a decade ago that estimates ranged form 8 billion to 20+ billion. 2) Their method of determining Hubble's constant has some room for error. They determine the masses exactly, but deducing the absolute value of the brightness based on the mass is not exact. 3) The scientists, as far as I can tell, have a sample size of one. I really think the journalist involved here didn't look critically enough at the information they were given. It does not seem to be newsworthy to me at this time. Thanks for posting it anyways though. -
Astronomy puzzle (angular-size/redshift)
Locrian replied to Martin's topic in Astronomy and Cosmology
I don't know the answer. I am therefore no use. Here is something I will try tomorrow though: when an object is around z=1.5 redshift, what will its angular size be, and how does this compare to the frequency of light we would be observing? I notice that both your articles have to do with radio waves, which will have a much, much larger wavelength than optical ones. Maybe that makes it more pronounced. There. I made a guess. Tomorrow (or sooner) I will find out if it has any merit. -
And, for the record, I will concede that if you twist yourself into knots and ignore the need to actually be able to predict what is going on in these systems efficiently, you can write off all of these interesting effects in such ways. However, it isn't useful, or even particularly logical. In materials with a positive index of refraction, varying phase and group velocities are trivial to write off. In anomolous dispersive materials, it requires more acrobatics, and begins to look very strange. In left handed materials, the explanations just sound absurd, and lead to terribly illogical conclusions. Such as the paper I cite above. I can post a couple more if anyone finds that of value.
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How would you like it? If you have access, here is the reference: Valanju et. al.,Phys Rev Lett, 88, p 187401. "Wave Refraction in Negative Index Media: Always positive and Very Inhomogenous.” Some choice quotes: Experimental confirmation of the things they claim to have proven impossible in the paper came about... well, about the same time the paper did.
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Right. With the small exception that the statement is physically inaccurate and logically inconsistent. A more correct response would have taken into account that the cesium trap and NI materials mentioned in the article have refractive indices that depend on frequency, and therefore the measurement of the group velocity isn't an acceptable measure of the speed the light is traveling. Saying something "appears" or "looks" to be traveling faster than light is ineffectual without giving a good reason for why it does.