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bio website motls.blogspot.com
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visits member for 4 years, 5 months
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Hi, I am a string theorist and a publicist.


Apr
4
revised Intuitive picture for spin-fluctuations contribution to specific heat of He3
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Apr
4
answered Intuitive picture for spin-fluctuations contribution to specific heat of He3
Apr
4
revised Why don’t photons interact with the Higgs field?
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Apr
2
revised Why don’t photons interact with the Higgs field?
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Apr
2
comment Why don’t photons interact with the Higgs field?
Please, keep it this way. They're not too extensive questions and may be easily answered on one page by the same persons.
Apr
2
answered Why don’t photons interact with the Higgs field?
Mar
31
answered Why is the Higgs boson spin 0?
Mar
30
answered How to interpret the derivative in the momentum operator in quantum mechanics?
Mar
29
revised Why are WW gg ττ branching ratios so similar for a 115 GeV SM Higgs?
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Mar
29
answered What is the interaction with Higgs field(s) that give the quarks so much different masses?
Mar
29
answered Why are WW gg ττ branching ratios so similar for a 115 GeV SM Higgs?
Mar
29
answered How can a Higgs decay to heavier products than its mass?
Mar
29
revised can one introduce magnetic monopoles without Dirac strings?
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Mar
29
answered can one introduce magnetic monopoles without Dirac strings?
Mar
27
comment Does a photon exert a gravitational pull?
Well, almost right except that the photons also carry a nonzero pressure, the spatial components $T_{ii}$, which also influence the shape of the metric tensor i.e. the gravitational field. In general relativity, not only the total mass or mass density but also the rest of the stress-energy tensor (density of momentum, flux of momentum etc.) affects the resulting gravitational field. Whenever a component of the stress-energy tensor changes, the gravitational field changes as well. That's what Einstein's equations clearly say. At infinity away from the photons, only the total mass matters.
Mar
27
comment Bell's theorem and why nonlocality is problematic
The comment above is echoed by physicists from many cultures. For example, Hawking in his "changed my mind" paper why information is preserved arxiv.org/abs/hep-th/0507171 shows that the path integral in the far future is still dominated by the trivial topology spacetime that doesn't see any causally separated interior. That's why the trivial-topology-calculation's qualitative result - the information may get out - is ultimately right. At any rate, locality is surely not "abolished" everywhere because of those insights.
Mar
27
comment Bell's theorem and why nonlocality is problematic
Dear Ron, it's not really right to say the "export of the information from the black hole" proves that locality is absent in gravitating theories in general. Locality is still 100% perfectly valid in gravitating theories around a Minkowski background. The information may get out of the black hole because the causal separation of the black hole interior is just an approximation; analogously, in quantum tunneling, information can tunnel through a finite barrier although it looks "robust" classically. However, there are still "infinite barriers" in Minkowski space that protect exact locality.
Mar
27
comment Bell's theorem and why nonlocality is problematic
Dear Ron, locality isn't dead. It's completely exact in the non-gravitational description of any theory, including the CFT in AdS/CFT, and even in the gravitating case, nonlocal effects are exponentially tiny, very restricted and careful, and have surely nothing to do with the explanation of entanglement experiments whether it's in AdS/CFT or anywhere else. Nathaniel: indeed, Einstein was among the people who was confused by basics of quantum mechanics in the 1920s but also 1930s and later. What makes the confused people in 2012 worse is that they had 50+ more years to understand; they failed.
Mar
27
comment Is all angular momentum quantized?
That's surely right and excitations in superconductors may have quantized spin. Still, it is hard to find that the background superconducting "medium" would be an angular momentum eigenstate. This won't really happen easily.
Mar
26
revised What's the classical limit of the pressure of the ultrarelativistic Bose gas
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