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bio website motls.blogspot.com
location Czech Republic
age 40
visits member for 3 years, 3 months
seen 16 hours ago

Hi, I am a string theorist and a publicist.


Feb
25
revised Do all light rays from a point passing through a thin lens converge at the image?
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Feb
25
revised Do all light rays from a point passing through a thin lens converge at the image?
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Feb
25
answered Do all light rays from a point passing through a thin lens converge at the image?
Feb
25
answered Why are some solitons formed from bosonic fields fermionic?
Feb
25
answered When lasers are used to cool atoms or ions, etc where does the heat go?
Feb
25
answered What is the boundary condition of graphene flake with zigzag edges?
Feb
25
comment Is it really possible for water to be held in a “cone shape” for a brief period of time?
I agree that is another thinner glass inside the big glass and no real video trick was needed.
Feb
25
comment How does one build up intuition in physics?
Good answer, David.
Feb
24
answered Does String Theory disagree with General Relativity?
Feb
24
answered What is the historical origin of the term action
Feb
24
revised Meaning of the Poisson bracket as a coordinate transformation
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Feb
24
answered Meaning of the Poisson bracket as a coordinate transformation
Feb
24
answered Why are the Higgs phase and the confinement phase identical in Yang-Mills-Higgs systems?
Feb
24
answered Why are baryons equivalent to Skyrmions?
Feb
24
comment Quantum mechanics on a manifold
Good, Moshe. Just to add a simple comment. Condensed matter physics has lots of projects looking at electrons in various bizarre situations - like quantum mechanics on graphs scholar.google.com/scholar?q=quantum+mechanics+on+graphs and the corresponding curved 2D versions. Electrons may be confined in any 1D or 2D submanifolds of our nearly flat 3D space, so people study it from this perspective.
Feb
24
answered Observation of cosmological topological defects
Feb
24
comment Scalar product of coherent states
Dear wsc, it is not true that $-(|a|^2+|b|^2)/2 +b^* a = -|a-b|^2$. First of all, a factor of two is missing. Second of all, the left-hand side has $b^* a$ instead of its real part, $(b^* a + a^* b)/2$, which appears on the right hand side. Because those quadratic expressions appear in the exponent, their difference - which is a purely imaginary number - only changes the phase of the result. So your latest geometric result is OK up to a wrong phase of the inner product. Just to be sure, Boy's answer 3 comments higher is exactly right.
Feb
24
revised With estimates of mass constraints on magnetic monopoles, how likely is one to be found by the LHC(MoEDAL)?
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Feb
24
answered With estimates of mass constraints on magnetic monopoles, how likely is one to be found by the LHC(MoEDAL)?
Feb
24
comment Most elegant/fundamental formulations of the laws of classical mechanics?
Dear Justin, I don't understand what you mean by "naturalness of the principle" and how such a naturalness may be "showed". The principle of least action is natural in the colloquial sense because experiments show that its predictions are obeyed in Nature; it is natural in the physics sense because it doesn't introduce new free parameters with values very different from one; and for a similar reason, it is a robust and universal principle. I am afraid that every other interpretation of "naturalness" you may have adopted is just totally unscientific. Maybe you just meant you're not used to it?