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Everything posted by Severian
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And do you think this is true in the West?
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Are you sure about that? Your first two objections (I stopped reading after that) are pure misunderstanding of what the BB model is, and I would have thought that any physicist should be able to tell you where you are going wrong.
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Just count the number of US election stories at http://news.bbc.co.uk/. We probably get spammed more than you guys.
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Do you think all men are created equal in modern Western society?
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Yes, exactly. The quadratic divergence that contributes to the mass is exactly canceled.
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No - it has nothing to do with mass. You can have massive particles which are their own antiparticle, no problem.
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Most? Have you observed one of a different spin?
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OK - let me try and answer this once and for all. The question "do virtual particles travel faster than light" is a somewhat ill defined question unless you define what you mean by a virtual particle and what you mean by its velocity (or momentum). Some people hold to the interpretation that: "In perturbation theory, systems can go through intermediate "virtual states" that normally have energies different from that of the initial and final states. This is because of another uncertainty principle, which relates time and energy." This is a quote from the page you link to. In that interpretation they define the energy of the virtual particle via [math]E^2 = p^2 c^2+m^2c^4[/math] and then say that since [math]p^2 c^2+m^2c^4[/math] is not equal to the square of the sum of the energies before (or after) the virtual particle was formed (or decayed), they say that energy was not conserved. This view is embodied in the Heisenberg uncertainty principle. In this view, the virtual particles can travel faster than light. This is not a violation of causality though since you can't measure them going faster than light. However, this is not the modern way of interpreting this. Energy conservation is probably one of the most fundamental laws we have, so modern physicists would rather hang on to it. So they say that energy is conserved, but [math]E^2 = p^2 c^2+m^2c^4[/math] is violated. Since this equation draws a 4d circle in Minkowski space, a particle obeying it is said to be on-mass-shell, while one disobeying it is said to be off-mass-shell, or just off-shell. The more off-shell a particle is, the shorter its lifetime, which is the modern embodiment of the HUP. In this interpretation, the virtual particle never goes faster than light. So which interpretation is correct? Both are, and neither are at the same time! Since you cannot experimentally tell them apart - there is no measurement you can make that distinguishes them - then they are equally valid viewpoints. This is why they are called interpretations.
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That is actually a very difficult question to answer. I think you could make a Newtonian universe, but whether or not this is complex enough to maintain stars, planets and ultimately life, is not clear. The vast majority of fundamental phenomena have relativity built into them, and I am fairly sure that many of the mechanisms that are essential for particular necessary phenomena wouldn't work without relativity. However, perhaps one could think up analogous Newtonian mechanisms to do the same jobs?
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In your opinion, do readers of the on-line version of the Economist represent a representative statistical sample of the world's population?
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Scuffle between Higgs and Hawking
Severian replied to Martin's topic in Modern and Theoretical Physics
Well, Hawking is right that it would be more "interesting" if there is no Higgs boson, because then we don't really understand what is happening and need to think up new ideas. I would be surprised if he was right though. -
Sunshine (2007 Film) Featuring Physics Commentary
Severian replied to Pangloss's topic in The Lounge
Does it? Artificial gravity and sound in space is insulting enough for me. -
The probability of decay is proportional to the Breit-Wigner distribution: [math]\frac{m \Gamma}{\left(E^2-|\vec{p}|^2-m^2 \right)^2 + m^2 \Gamma^2}[/math] where [math]\Gamma[/math] is the particle width and I have neglected the [math]c[/math]'s.
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I'm ready to tell you my secret now...I see dumb people
Severian replied to ParanoiA's topic in The Lounge
I am an old fart too, but I have to agree. In this country we even have a TV programme in much the same spirit as your rant. It is called "grumpy old men" and it is interviews with men of a certain age, with them ranting about society. It is very funny, but oh so true. http://en.wikipedia.org/wiki/Grumpy_Old_Men_(TV_series) http://www.bbc.co.uk/comedy/previews/grumpyoldmen.shtml -
It depends on what quality of life you think is necessary. If I didn't understand calculus, my life wouldn't be as fulfilled as it is.
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It has a wiki page http://en.wikipedia.org/wiki/Technicolor_(physics)
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Actually, despite all the nay sayers in this thread, the premise in the OP is probably correct, in some form or another. First of all, most of the mass of you or I comes about from the interactions of the strong force. Even if all the fundamental particles were massless, we would still have mass because the energy binding the quarks together in the proton gives the proton an effective mass. So in some sense at least, mass comes about through interactions and therefore charge (though in this case color charge, not electric charge - the electromagnetic interaction also contributes , but its effect is tiny). Even at a fundamental level, many scientists believe that particle masses arise from the same idea - from an interaction. This could be a new force like the strong force which we just haven't seen yet (this theory is called technicolor). But even if the vanilla Higgs mechanism is true (the mechanism most physicists think will be true) then we also have mass from interactions. In this theory the mass is directly generated by a coupling to the Higgs boson - the Yukawa interaction - and the particle's mass is directly proportional to the coupling, or in other words the particle's Yukawa "charge". The only sense in which the Yukawa interaction is not a charge is that it is not linked to a symmetry.
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It is amazing how so many intelligent people can expend so much effort investigating something completely pointless. Hey, this thread is just like String Theory...!
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I have a school friend who became a marine biologist and apparently now spends all his time scuba diving in the Caribbean. Doesn't sound like a bad life.
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It doesn't work for real photons, that is ones that obey [math]E=|\vec{p}|[/math]. Try it for yourself! Consider 3 photons with energies [math]E_i[/math] and momenta [math]\vec{p}_i[/math] where [math]i=0,1,2[/math]. Now set [math]E_0=E_1+E_3[/math] and [math]\vec{p}_0=\vec{p}_1+\vec{p}_1[/math] for energy and momentum conservation. Now check the mass-shell condition for particle 0, given particles 1and 2 obey [math]E_{1,2}=|\vec{p}_{1,2}|[/math]. It works for the case where one is absorbed and remitted because the intermediate photon can be virtual. Which is of course why it has to re-emit the photon so quickly.
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I think nuclear already is a better alternative than solar power. In fact, you could use the argument the other way - spending money on developing solar power distracts from the real goal, which should be the development of fusion power. Since fusion is a form of nuclear power, ramping up to build lots of fission power stations now, will provide us with the expertise and social acceptance (and perhaps even the political will for the funding) for the building of fusion reactors 30-50 years from now. That is not to say that solar can't be used in certain circumstances, perhaps to augment other power sources. But it will never be viable as our only means of energy generation, especially far away from the equator.
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Electromagnetic Wave have momentum
Severian replied to Ashish's topic in Modern and Theoretical Physics
Yes, that's right - I wasn't meaning to diminish de Broglie's achievements. Having said that, there have been plenty horrible Nobel Prizes. I hear Cabbibo is furious about this year's. -
No - because the evidence indicates that dark matter doesn't clump in small distance scales.
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Science and religion mix fairly well in my life.
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neutrino-antineutrino annihilation
Severian replied to bob000555's topic in Modern and Theoretical Physics
Take a look at this: http://en.wikipedia.org/wiki/Double_beta_decay It is not quite the same but almost. The Neutrinoless double-beta-decay experiments are trying to show the neutrino is its own antiparticle, but the rate for your experiment would be comparable to the rates they will get if their hypothesis is correct.