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Apr
28
comment How many observations over an atom can be made?
Every measurement impacts the electron - or any physical system - in quantum mechanics. How long you may play - it depends what property of the electrons you measure. For example, if you measure the energy, you get one of the allowed energy eigenstates, and it's there again. Instead, if you decide to measure the exact location $\vec r$ of the electron, you may get it but the momentum $\vec p$ becomes infinitely uncertain after the measurement, by the uncertainty principle. This corresponds to almost 100% certainty that the momentum is large enough for the electron to escape the nucleus.
Apr
28
revised Is multiplication in physics purely mathematical or is there a physical explanation to it?
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Apr
28
answered Is multiplication in physics purely mathematical or is there a physical explanation to it?
Apr
28
comment Fine structure constant and unit conversion
If you read e.g. articles about some X-rays relatively to the LHC, a TeV could get converted to a keV from the X-rays, and there would be $10^{6}$ there, too. But I understand your explanation why it happened, too.
Apr
28
revised Derivation of Biot Savart law for a curve
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Apr
28
answered Derivation of Biot Savart law for a curve
Apr
28
comment Fine structure constant and unit conversion
It's very attractive to say that mega, $\text{M}$, is one thousand, because the lowercase $\text{m}$, or "milli", is one thousandth. ;-)
Apr
28
revised Fine structure constant and unit conversion
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Apr
28
answered Fine structure constant and unit conversion
Apr
28
comment Why is hot wood ash more fluid than cold ash?
I just found out that a dirty cooking stove is much easier to be cleaned when it's hot ;-) and the mostly solid oil dirt at various places partly melts. ;-) Isn't your observation also just a case of simple melting of some parts of the material? Solids, when warmed up, become liquids, right? Note that wood doesn't melt because it gets burned before it melts, but ash could.
Apr
28
answered How to motivate the importance of the spacetime interval
Apr
28
revised Does QM unequivocally violate the law of bivalence?
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Apr
28
revised Why is capacitance defined as charge divided by voltage?
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Apr
28
revised Does QM unequivocally violate the law of bivalence?
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Apr
28
comment Does QM unequivocally violate the law of bivalence?
I would bet that the conclusion of many of you that the original person who made a similar statement was deeply confused about QM is just wrong. The statement was probably just a provocative, but rather rigorous formulation of the usual principle of quantum mechanics that one can't assume that observables have one of the well-defined values even in the absence of an observation. E.g. one can't assume that a particle in the double slit experiment went through one slit or the other slit, with the classical implication of this assumption on the calculation: the assumption neglects interference
Apr
28
comment Does QM unequivocally violate the law of bivalence?
I can understand it. There's lots of confusion and idiosyncrasies. But there's this more specific question in the context - whether the person who originally made the statement that "QM refutes the principle of bivalence" was clueless and didn't know what he was talking about. I would bet (it's more likely) that this person knew his stuff (quantum mechanics) very well. The statement may have been just a "logician's way" of saying the usual fact that in QM, one can't assume that observables have one of the well-defined values even without an observation.
Apr
28
revised Why is capacitance defined as charge divided by voltage?
added 768 characters in body
Apr
28
answered Why is capacitance defined as charge divided by voltage?
Apr
28
comment Does QM unequivocally violate the law of bivalence?
All of science is based on the fact that various propositions are known with some probability. When we combine many statements in various ways, the probability of the combined statement is close to 0% or 100%, which allows us to say that the combined statement is true. Such true statements may be derived from the probabilistic laws of physics. For example, people don't walk through the walls. Again, what quantum mechanics predicts are absolutely the same probabilities as those in classical statistical physics. They have exactly the same interpretation - they're just calculated differently.
Apr
28
comment Does QM unequivocally violate the law of bivalence?
You may completely misunderstand how the axioms of probability follow from the underlying logic but that doesn't change the fact that they're directly derived. For example, the Liouville equation for the distribution on the phase space may be directly derived from the Hamilton equations for "x" and "p". To say that they have nothing to do with each other is absolutely preposterous. It is also nonsense that we can't talk about probabilities of logical propositions.