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bio website sjbyrnes.com
location Massachusetts
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visits member for 4 years, 3 months
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Jan
9
comment Local EPR-experiments with photons in vacuum?
Indeed, I am saying that the term "null interval" in special relativity has a very very different definition than an "empty interval" in the sense of intervals of real numbers. If you don't believe me, try looking up the former definition in an SR textbook, and then looking up the latter definition in a high school math textbook. You will see that they are completely different and unrelated.
Jan
9
comment Local EPR-experiments with photons in vacuum?
Sometimes words have multiple meanings. You found an article called "Interval (mathematics)" which has a certain definition of "Interval". But you are wrong to conclude that this is the universal and only definition of the word "Interval". The more relevant article is en.wikipedia.org/wiki/Interval , which proves that the word "Interval" has at least 15 different definitions. The word "interval" in the context of special relativity means something different than the the word "interval" in the context of the number line, just as it means something different in music, or in sports. :-D
Jan
9
comment Local EPR-experiments with photons in vacuum?
When you say "all properties of an interval", I think you mean "all the properties that I intuitively expect an interval to have", but your intuition is wrong because your intuition is based on a lifetime of experience with Euclidean geometry. Well, you're entitled to have the opinion: Anything that deserves to be called an interval must certainly have the following properties...!. But you must understand that other people do not feel this way. That's why I suggest that you mentally replace the word "interval" with "shminterval", a made-up word which is therefore free of your preconceptions.
Jan
9
revised Local EPR-experiments with photons in vacuum?
added 13 characters in body
Jan
9
answered Local EPR-experiments with photons in vacuum?
Dec
14
answered Spectral properties in Solid state physics
Dec
10
comment Is there a relation between (non-) existence of magnetic monopoles and thermodynamics?
I don't understand what point you're trying to make. Are you trying to prove "If there are magnetic monopoles, nothing is thermodynamically reversible?" Or "If there are magnetic monopoles, then everything is thermodynamically reversible?" Or "If there are magnetic monopoles, the second law of thermodynamics is false"? Or what?
Dec
10
answered Is there a relation between (non-) existence of magnetic monopoles and thermodynamics?
Dec
9
awarded  Guru
Dec
9
accepted Why does a thermoelectric generator need both p and n elements?
Dec
8
answered What is the right order of creation operators?
Dec
8
answered Stimulated emission direction
Dec
8
answered Faraday's paradox
Dec
7
revised Consequences of the new theorem in QM?
added 130 characters in body
Dec
7
comment What limits the doping concentration in a semiconductor?
Well, you can write it in terms of "enthalpy of mixing" etc. But if you tell me two atoms, I cannot tell you the solubility limit (or the enthalpy of mixing or anything else useful) except by experiment or numerical simulation.
Dec
7
answered What limits the doping concentration in a semiconductor?
Dec
4
comment Stimulated emission direction
You should look up optical amplifier - scholarpedia.org/article/Optical_amplification en.wikipedia.org/wiki/Optical_amplifier and more specifically gain guiding rp-photonics.com/gain_guiding.html
Dec
4
comment Why does a thermoelectric generator need both p and n elements?
I don't see any reason that ohmic losses are an inevitibly large problem in the design I drew, if you make reasonable choices about geometry etc. I agree that a large voltage is more practically useful in the final output, but it's not a big deal, you can always put a step-up voltage converter at the device output.
Dec
4
comment Why does a thermoelectric generator need both p and n elements?
Copper has 400X larger thermal conductivity than BiTe. So if you compare the heat conductance of a 1-meter-long, 1mm-diameter copper wire with the heat conductance of a 10cm^2, 1mm-thick BiTe, the BiTe will conduct more heat than the copper wire ... by a factor of 2000.
Dec
4
comment Why does a thermoelectric generator need both p and n elements?
You say "heat will be conducted away from the hot junction by the wire itself, so no electricity will flow." (I assume you mean "electrical current" not "electricity".) I don't understand how you reach that conclusion. Some heat will surely flow through the wire, but not all of it, indeed probably almost none of it. A long thin copper wire has a very low thermal conductance. In the design I drew, it is entirely possible to have 99% of the heat flow through the thermoelectric material and 1% flow through the wire. Then why should heat flow through the wire make any difference at all?