we all know spent fuel rods taken out from a reactor core keeps generating tremendous amount of heat and needs to be kept cool by running cool water. it is also known that if cooling system fails water will evaporate quickly leading to a blast and meltdown
if the fuel can still produce so much h...
@Slereah In order to do that rigorously, you have to do a classical limit; for (nonlinear) RQM is the classical theory corresponding to QFT. To feel better you may see the parameter that goes to zero not as Planck's constant but as the inverse of the number of excitations (i.e. a mean field limit).
"In the early days of quantum field theory maintaining symmetries such as Lorentz invariance and proving renormalisation were of paramount importance. The Schrödinger representation is not manifestly Lorentz invariant and its renormalisability was only shown as recently as the 1980s by Kurt Symanzik (1981)."
@ACuriousMind : Baez makes it clear that Einstein talked about the speed of light changing. He's being a little bit diplomatic with the pseudo=speed. See [the old version]-desy.de/user/projects/Physics/Relativity/SpeedOfLight/…) of this article...
Note where it says of Einstein's variable speed of light: "This interpretation is perfectly valid and makes good physical sense, but a more modern interpretation is that the speed of light is constant in general relativity". Then look at the final line: "Finally, we come to the conclusion that the speed of light is not only observed to be constant; in the light of well tested theories of physics, it does not even make any sense to say that it varies.".
@ACuriousMind The only way I know to obtain RQM dynamics (let's say Free Klein-Gordon) from a "more fundamental dynamical theory" is as a limit of a free scalar QFT. This type of limit is called a classical limit, since it is perfectly analogous to the limit $\hslash\to 0$ of QM. Nevertheless, in this context it may better be seen as a mean field limit, where the number of excitations of the field goes to infinity, and each single excitation (particle) can be described by an effective dynamics.
I am not aware of other methods to "reduce" QFT to RQM.
I suppose the questions I'm posting them on are being deleted, because I'm pretty sure that I've posted my Not a HW Help site auto-comment more than the 91 times cited here
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I answer a lot in the comments because I don't like giving partial answers and I often don't feel like taking the time to properly reference and write a good answer
I don't use "because that famous guy said so" in my answers. I only use the explanations they might give. It's not enough that someone says something, they need to back it up with reasoning
@obe Let's not be suggesting that for my next name change
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