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Jun
5
comment Lacking of scale and distribution moments
Dear @Oli, fine, it depends how cleverly you define it. A straightforward integral has two canceling log divergences. By principal value integrals, symmetric ones, the mean value is zero as the distribution is even.
Jun
5
revised Lacking of scale and distribution moments
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Jun
5
answered Lacking of scale and distribution moments
Jun
5
comment top quark and Z,W bosons?
One also fails to conserve the color in the original decay - a confined colorful particle can't decay to colorless ones such as W,Z. ... I am utterly unimpressed by the "coincidence" that the sum of two particles' masses is a third particle mass within 1%. I wouldn't even call it a coincidence. It's just a description of one of the normal situations.
Jun
5
awarded  supersymmetry
Jun
3
reviewed Approve What is “code” in “toric code”?
Jun
2
answered Why droplets of water under oil explode when heated
Jun
2
reviewed Approve Why do we use Planck's constant?
Jun
2
comment Why is there a phase factor when the two composite angular momentum is exchanged in Clebsch–Gordan coefficients
Well, $|j_1m_1\rangle$ surely is a full description of the state assuming that by "state", we mean a vector in the Hilbert space up to a phase or normalization (the physical definition of a state). So they're full descriptions of the state up to a phase - a non-degenerate eigenstate of a complete set of commuting observables is unique up to a phase. But the phase is exactly what is allowed to change under permutations etc.
Jun
2
revised How did Halley calculate the distance to the Sun by measuring the transit of Venus?
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Jun
2
revised How did Halley calculate the distance to the Sun by measuring the transit of Venus?
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Jun
2
revised How did Halley calculate the distance to the Sun by measuring the transit of Venus?
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Jun
2
revised How did Halley calculate the distance to the Sun by measuring the transit of Venus?
added 583 characters in body
Jun
2
revised How did Halley calculate the distance to the Sun by measuring the transit of Venus?
added 583 characters in body
Jun
2
answered How did Halley calculate the distance to the Sun by measuring the transit of Venus?
Jun
1
reviewed Approve How much energy is in a lightning strike?
Jun
1
comment How to prove Galilean invariance?
It's a real mess. What does it have to do with the simple problem of Galilean invariance? Just replace all $\vec x\mapsto \vec x+ \vec V t$ and $\vec v_i\mapsto \vec v_i+\vec V$ and check that Newton's equations hold if they held before. That's simple because the relative distances won't change and the dependence on derivatives is only on accelerations where $\vec V$ cancels.
Jun
1
comment Majorana zero mode in quantum field theory
Thanks for your interest. Maybe you may start with arxiv.org/abs/cond-mat/0609556 and some literature mentioned in it.
Jun
1
comment Reference for the ${\cal N}=3$ Chern-Simons Lagrangian at general $N_c$, $N_f$
It's inevitable that there are equations such as 2.8 that are "out of the blue". This is the first equation that has the SUSY enhanced to $N=3$. There isn't any "mechanistic" method to write down actions with interesting or given symmetries or other properties. If one wouldn't be able to guess eqns such as 2.8, it doesn't mean that others couldn't guess it, either. They could and one may verify that it has the desired properties - and one should learn some lessons how such actions may look like so that he has a higher chance to "guess" in the future.
Jun
1
comment Reference for the ${\cal N}=3$ Chern-Simons Lagrangian at general $N_c$, $N_f$
Hi, the equations 2.1-2.3 use the ordinary $N=2$ superspace, as they write down on the left hand side. It's the same number of supercharges as the normal $N=1$ in 4 dimensions. You may think of the $N=2$ theories in $d=3$ just as about 4-dimensional theories dimensionally reduced to $d=3$. So the decompositions are the same and the rewriting does lead to 2.4-2.7 and other equations. When you realize it's the same maths as in $N=1$ $d=4$, you will find such calculations in most of the standard SUSY textbooks.