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7

It is "easy" to show that the cross-section of the 2 reactions: $$(1)~~~\nu_{\mu} + d \to \mu^- + u~~~~~~(2)~~~\bar{\nu}_{\mu} + u \to \mu^+ + d$$ are different. The naive calculation gives a factor $\sigma_1/\sigma_2 = 3$ as shown below. The fact that the figure in the particle data group gives actually almost a factor 2 needs to take into account the ...

3

The answer is that in general cross section of particles and antiparticles are different. For this case in specific there is one point that Dirac particle have four possible states: due two possible ranges for energy E<0, E>0, and two possible range for helicities h>0 and h<0. In the standard model of particles only the neutrino with h<0 interact ...

3

Here is the elementary particle table from which all others are built up , the standard model of particle physics. Which shows the conserved quantum numbers that characterize the particles (columns and rows have quantum numbers assigned too) plus the measured masses. The quantum numbers have to "annihilate" to have an annihilation event, i.e. they should ...

-4

I wrote a paper in which I show that the electric field of a charged particle can be described as composed of two quanta. Two types of quanta are enough to describe the electric field, the magnetic field and photons. It was shown, why electron does not fall into nucleus and why annihilation happens between particle and anti-particle. A more deep explanation ...

0

Classically a black hole made from collapsed matter would look (to people on the outside) exactly the same as a black hole made from collapsed anti-matter. They would absorb things the same and the curvature outside would be the same so everything would orbit it the same way and get pulled in the same way. What's interesting is the word black hole refers ...

3

If we take the Milky Way as an example, the black hole at the centre, Sagittarius A$^*$, has a mass of about 4 million times the Sun. However the mass of the Milky Way is somewhere around a trillion Suns. So the central black hole makes up 0.0004% of the total mass. So even if our central black hole was pure anti-matter it wouldn't come close to accounting ...

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