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Everything posted by DrRocket
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Right. Unfortunately some well-known physicists have recently published books for the general public that have about as much foundation as the gurus mutterings. See Hawking's The Grand Design or Steinhardt and Turok's Endless Universe: Beyond the Big Bang. It seems to me that before one uses M theory to solve the mysteries of the universe one ought to settle the major open question of M theory -- namely "What is M theory" ? Mysticism is mysticism.
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adjoint versus classical adjoint
DrRocket replied to 123acsiac's topic in Linear Algebra and Group Theory
The only relationship is unfortunate terminology. -
This is not a mathematical issue and no "amount" of mathematics will help you. No one knows how much energy is in the universe. There are legitimate points of view that hold that it may well be zero. Energy in the universe has no clear connection to the structure of the solar system. Existence or non-existence of God is not a scientific question. Your approach is going nowhere.
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Rubbish
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Boy, are the particle physicists and quantum field theory folks in for a surprise !
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TNT, with a boost from a blasting cap detonates. That means that combustion proceeds along a front, at the (very high) local speed of sound due to adiabatic compression Pressures at the detonation front are extremey high and the wave is very fast, typically several kilometers per second. TNT detonation velocity is 6,940 m/s. The result is a very fast evolution of gas and a very strong blast wave. Black powder deflagrates. This is a much slower process in which combustion is initiated by radiatuve heat transfer. The result is much slower gas evolution and a lesser blast. http://en.wikipedia.org/wiki/Detonation (Note that this Wiki article concentrates on detonation in gasses. Detonation of solid and liquid explosives is a more violent process.) http://en.wikipedia.org/wiki/Deflagration
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Assuming that the poster used "POS" as you suggest (a reasonable assumption), one would conclude that he does not like Obama. The degree of passion is not something that I can judge from the post, as idioms used by the young don't seem to connote the degree of passion that one might ascribe to the speaker were he older. The epithet did not seem sufficiently repulsive to Moontanman to preclude its use in his response. It is not at all clear that the dislike of the poster is directed towards the person of Obama as opposed to the policies and actions of Obama. The content, as opposed to vitriol, in this thread has been rather sparse from the beginning. While the attack may have been against the person, it also may not have been. Lacking anything approaching a basis for anything in this thread, no opinion of any gravitas could follow "from the argument presented". However, the poster could well have formed a valid opinion from other sources. It is not hard to form a perfectly logical position in opposition to the policies of virtually any modern politician. I cannot therefore accept that the opinion of the poster is baseless, only that the basis is not presented in this thread. It lies in several places: 1} The choice of the words "hater" and "hate". These words have in recent times come to connote feelings and actions taken against minority groups with no reason other than their minority status. "Hate crimes' are seen as particularly heinous. But who ever heard of an "empathy crime" ? Calling someone a hater in modern parlance is every bit as serious as are racial slurs. I have seen real haters, modern Nazis and KKK members, first hand and I would consider being lumped with them as a "hater" as much an insult as would a black man being labeled with the "N" word. 2) Passionate dislike is not, in modern context, the same thing as hatred. One can have a passionate dislike for the principles represented by a politician without hating the individual. One ought to be given the benefit of the doubt, particularly given the imperfect nature of communication in a forum such as this, that one's stated opinions are not based on racism or any other manifestation of hatred without clear evidence to the contrary. To do otherwise is a version of bigotry seen in some groups of intellectuals. It is not redneck bigotry, but it is bigotry nonetheless. 3) Labeling the OP as a hater, suggests that his opposition to Obama is based on Obama's membership in a minority group (as I understand it he is either black or Hawaiian), one of the groups against which "hate crimes" can be committed. There is no basis evident for such a characterization of the OP. I don't know why he opposes Obama, but lacking any clear evidence of racism, I am unwilling to even imply such motivation. By refering to him as a "hater" he is so described, by inuendo. Employment of such inuendo, lacking evidence in the same manner that you ascribe to the OP in the formation of his opinions, is itself a form of bigotry. In no way am I defending the OP's labeling of the President as a POS. I certainly defend his right to do so (not necessarily here). I deplore his choice to exercise that right in such a fashion. BTW, I think Obama's decision to send the Seals after Osama was exactly the right decision in the situation as presented. It was important to get Osama and to know that is was indeed Osama that was killed or captured. Special Operations was the right choice. On the other hand the pictures of Obama and his ctowardabinet watchingreferringinnuendoinnuendo the TV while the operation unfolded were a bit gratuitous. I could not care less about his speech -- if you've seen one political spin, you've seem 'em all.
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Your point is clear as mud. Bush has been out of office for over two years. His National Guard record is now about as relevant as Teddy Roosevelt's organization of the Bull Moose party. It is several years too late to worry about pecadillos of Bush (eitheer one). As far as Obama's birth certificate goes, I have a hard time understanding why it took so long to produce one. I was required to produce an original birth certificate to renew my driver's license. Is a birth certificate too much to ask of the Presdent of the United States ? As your citation carries no date, and as Obama only very recently released a certificate, it is not unlikely that the cited article is not timely in any case. Why flog dead horses ?
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That sounds like the right approach in geberal. A lot depends on the character of the post doc. If you will be working in someone's research group, then they will be looking for someone who "fits in" and whose expertise adds to and complements the group. If you will be on your own to pursue your own individual research then they will be looking for technical prowess and someone who adds to the department and can handle whatever instructional duties come with the position. Letters of recommendation from known entities will count for a lot.
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That, by inuendo, is an extraordinary display of bigotry. No one else has used the word "hate" in this thread. Those who disagree with Obama are no more "haters" than those who disagreed with Bush. I hesitate to think what categorization must apply to those of us who disagree with both of them.
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Kinetic energy is dependent on the frame of reference. Relative to you that football that you tossed has kinetic energy. But in the frame of the football it is at rest and you have kinetic energy. Potential energy likewise depends on a choice of references. One can speak of a difference in potential energy between two states, but there is no absolute measure of potential energy. So if you put the football on the roof of your house, you apply a force over a distance, do work, to lift it from the ground to the roof, just as you did work to throw it and put it into a relative state of motion from a relative state of rest. In the case of the ball on the roof that work can be recovered and turned into kinetic energy if the football falls off of the roof back to the ground. In either case the energy is associated with the work done to move the football from one state to another.
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Not a bad book, but not a good introduction either. It is really a cross between what is taught in a real analysis course and a functional analysis course -- functional analysis usually follows real analysis. In my opinion it is too heavy for a real analysis course and way too light for a functional analysis course. I am not surprised that you gave up on it. For your purposes a course that does analysis on [math] \mathbb R^n[/math] properly, rather than dealing with more abstract spaces, would be appropriate. Two of the best are Elements of Real Analysis by Bartle and Principles of Mathematical Analysis by Rudin. (Bartle is the easier of the two). The next level would be Rudin's Real and Complex Analysis or Folland's Real Analysis: Modern Techniques and Their Applications, and then Rudin's Functional Analysis. Before you tackle functional analysis a good course in point-set topology is needed and some abstract algebra is helpful. You may observe a recurrence of the name Rudin. There is a reason for that. His three analysis books are classics and have been the benchmark in advanced undergraduate and graduate analysis texts for many years. For chemistry I would think that things like Fourier analysis (for spectroscopy) and operator theory (for quantum mechanics) would be the major areas of interest. Those come under the heading of functional analysis, though you will find much good material in Rudin's second book. Analysis is just the extension of calculus. There are LOTS of applications. Fourier series, Fourier transforms, ordinary differential equations, partial differential equations, Hilbert spaces, and operator theory are subjects in analysis. However, most mathematics classes will not directly discuss specific applications. The specific applications are better discussed in classes dedicated to the application. The heat equation, for instance might receive some attention in a PDE class, but heat transfer would not be discussed in any detail. ' I would avoid "applied mathematics" classes. In my experience so-called "applied mathematicians" are weak in two areas -- mathematics and applications. If you want to see good applications of mathematics look to the more theoretical chemists, engineers and physicists.
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You are indeed mixing quantum theory and general relativity. Nobody knows how to do that, yet. The gravitational waves of general relativity do propagate at c. Buthe they are waves of spacetime curvature, "disturbances of the grid" rather than something that propagates 'through the grid". Worse, there is no universal grid. There is no easy answer. I think it will take an eventual unification of gravitation with quantum theory to answer your question. Such a theory has remained elusive. The problem with "logical/philosophical" rather than mathematical formulations of and approaches to such questions, is that the "logical/philosophical" language of everyday experience is completely inadequate for questions of quantum theory and relativity which do not fit that everyday experience. The language of physics is mathematics. In order to understand it you must speak the language.
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This a great idea. Politicians should have to pay every time they exhale.
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?????????/ That is essentially the definition of supersymmetry.
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Just selected people. Suicide is pretty much a sure cure for angst.
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GR is a mix. The basic idea, while a bit abstract, is incredibly simple. But the devil is in the details, and solving the equations explicitly is indeed incredibly hard. The fundamental equation, up to a constant, [math]G= 8 \pi T[/math], is simplicity itself. The hard part is deducing the implications.
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You simply prove the point that you are clueless about the theory that you purport to refute. Pitiful. There is essentially no difference between the Timex on the wrist of the "stay at home twin" on Earth and time based on counting revolutions of the Earth. They will each disagree with the clock of the "space cadet." This effect has been demonstrated rather conclusively by experiment. You are arguing against hard empirical data. Would also like to argue that bumblebees can't fly ? You clearly have extreme difficulty in differentiating between a "cogent point" and complete nonsense. That is reflected in your continual arguments against your own personal misconceptions about what relativity actually says. My Labrador puppy understands it better -- he doesn't "know" so many things that are just plain false. No, because the basis for the discussion is general relativity, and it is a fact that time in general relativity is not universal. It is also a fact that thus far general relativity is consistent with what is actually observed, which is contrary to the notions that you espouse. You would well to pay attention to facts. Observation also shows that it is a fact that you don't understand the content of the general theory of relativity and therefore it is a fact that your straw man arguments are logically fallacious. Ontology based on ignorance and delusion is hardly a valid inquiry into existence. “It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong” – Richard Feynman Yeah, I do tend to ignore illogic and lunatic rants. I probably will continue to do that. Life is too short. Presentism is contradictory to the FACTS that support the special and general theories of relativity. It is a fact that clinging to ideas that are contrary to what has been observed and confirmed is irrational. "There is no position so ridiculous that it has not been held by some philosopher." – Cicero More illogic. Go read what I said, not what you wish I said or what you hallucinate that I said. You desperately need to learn some basic physics and mathematics. Arguing against that which you do not comprehend is just plain silly. Arguing against empirical data is way beyond silly. REALITY is that the local nature of time was shown in the Hafele-Keating and Pound-Rebka experiments. Reality trumps delusion. Those are the facts ma'am, just the facts. "A man who carries a cat by the tail learns something he can learn in no other way." – Mark Twain
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It is an excellent place to talk about physics. You did not do that. What is scary to me is that you might think that you did.
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At this level it is all interesting. I am an analyst.
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Science Club advisor seeks information relevent to Zoology
DrRocket replied to MLyn's topic in Science Education
How about a field trip, maybe including some camping, in the mountains nearest you ? That should provide an opportunity to locate, identify, and observe several species. You might also consider tidal pools on the beach. -
This is all completely irrelevant. Like any other creative research scientist Einstein entertained many ideas. What counts is the final product, not the many avenues investigated as part of his research program. That final product is general relativity. You continue to exhibit lack of understanding of that theory and you continue to argue against a sraw man. BTW Einstein also opined that time is probably, at the most fundamental level, statistical in nature. He was unable to turn that into a useful theory. Einstein is so often quoted and misquoted that, much like the Bible, you can find an Einstein quote to support almost anything. "Isn’t all of philosophy as if written in honey ? Something may appear clear at first, but when one looks again it has disappeared. Only the pap remains." – Albert Einstein And my personal favorite: "I have reached an age when, if someone tells me to wear socks, I don’t have to." – Albert Einstein Pointing out gross lack of understanding of the subject matter is hardly an attack on you. It is an attack on your arguments. It is a logical necessity since you argue against aspects of the general theory of relativity that exist nowhere other than in your own mind. You have just provided clear evidence of the fact that you argue against a straw man. You don't understand that you don't understand. You refuse to put forth the effort to understand what the theory actually says. This makes logical dialogue essentially impossible.
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I hate to burst your bubble, but in terms of differential geometry a cylinder is flat. You can roll the surface isometrically onto a plane. Maybe you should regroup and learn enough mathematics to understand curvature a it. There is no simple explanation of Riemannian curvature.