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bio website motls.blogspot.com
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Hi, I am a string theorist and a publicist.


21h
comment What exactly does $S$ represent in the CHSH inequality $-2\leq S\leq 2$?
Dear dk, local realist theories imply that $|S|\leq 2$ is true, i.e. it always hold. The negation of this statement is that $|S|\gt 2$ holds at least sometimes. So it's enough to find one example where $|S|\gt 2$ and all local realist theories are ruled out.
1d
awarded  Explainer
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28
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28
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21
comment Anti-neutrons, anti-quarks, isospin: What is observed and what is derived?
Well, yes, no, even Majorana neutrinos are in principle different from the antineutrinos because the words "neutrinos" and "antineutrions" get correlated with the helicity. It's the same species but if you see a quickly moving particle, you may say whether it's what is called "neutrino" or an "antineutrino" - the Majorana means that the Lorentz-invariant multiplet must contain both of them.
Sep
21
answered Anti-neutrons, anti-quarks, isospin: What is observed and what is derived?
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21
awarded  Nice Answer
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20
answered Why does Energy-Momentum have a special case?
Sep
19
comment what physical quantity do real scalar field operators create/destroy?
It is a quantum number with eigenvalues $+1$ and $-1$, so it's a form of parity, but an unrelated parity to the usual reflection in space. It reflects the sign of $\varphi$. Equivalently, it's $+1$ if the number of the quanta is even, and $-1$ if it is odd. The operator $\varphi$ may create or destroy but whatever it is, it changes an even number to an odd one or vice versa. So the parity of the number of particles always changes by $\varphi$, and if the Hamiltonian is even in $\varphi$ or its derivative, this parity is conserved.
Sep
18
comment Inconsistency between Helmholtz and Gibbs Free Energies
Oops, I think that you are completely right - at equilibrium, G is constant. answers.yahoo.com/question/index?qid=20110806205610AAF8EbM
Sep
18
comment Inconsistency between Helmholtz and Gibbs Free Energies
Hi Tom, well, take a mixture of water and ice at the melting point. It has a well-defined pressure, temperature, and number of molecules, but the fraction the ice may be anything - you have to add one full intensive variable (the percentage of ice) to describe the system. So G can have any value in an interval for those values. This mixture of ice and water is really an optimized replacement of some "forbidden part" of the phase diagram.
Sep
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answered what physical quantity do real scalar field operators create/destroy?
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16
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