# Tag Info

3

Frankly I find this so-called pedagogical article quite unintelligible and fail to see what the author wanted to say about these two operations. I also can't make any sense of the "derivation" of 7.3 based on the chiral projection being a "numerical matrix" and therefore commuting with charge conjugation operator. Moreso the remark: Elaborate statements ...

2

But they do decay into the channels available from conservation laws. Annihilation happens when all the quantum numbers cancel. In the pio the charge and baryon number of the quark antiquark cancel each other, and the decay particles add up to zero quantum numbers. The $\pi^0$ goes into two photons as soon (electromagnetic interaction rates) as it is ...

3

After thinking about it some more, I think I have a resolution. Consider a single Weyl fermion, which has equation of motion $$\sigma^\mu \partial_\mu \psi = 0.$$ Just like the Dirac equation, the Weyl equation is linear in momenta and hence has negative energy solutions. We then perform the usual procedure to regard these as positive energy solutions ...

0

The Heisenberg uncertainty principle is a basic foundation stone of quantum mechanics, and is derivable from the commutator relations of the quantum mechanical operators describing the pair of variables participating in the HUP. You are discussing the energy time uncertainty, . For an individual particle, it describes a locus in the time versus energy ...

2

This is science fiction: What will happen if we somehow create an "anti-sodium "element and react it with "hydrogen"(not anti)? As John notes it is very hard to make antimatter: antiprotons are easily made in proton proton scattering, and positron with gammas, but as we know, the energy levels at which the electron is trapped about a proton is of ...

5

The annihilation of electrons and positrons goes cleanly to two photons, but the annihilation of brayons and antibaryons is a far more complicated process. This is because baryons are composite particles made up from (on average) three quarks. I discuss this in Are there different kinds of antimatter reactions?, where I show that a proton-antiproton ...

3

We would get anti-Neon... and some anti-fluorine from hydrogen anti-Neon collission Ref: https://www.quora.com/If-I-could-manage-to-fill-a-glass-with-anti-hydrogen-and-mixed-it-with-an-equal-amount-of-water-would-it-produce-oxygen

25

Mesons are not elementary, they are composed of quarks. So take a look at their quark content. The charmed eta meson consists of a charm and an anti-charm quark, denoted $c\overline{c}$. An anti charmed eta meson would therefore be an anti-charm and an anti-anti-charm (which is just a charm) quark, i.e. $\overline{c}c$, which is obviously the same as ...

18

Interstellar space is an excellent vacuum, but it's not a perfect vacuum. For example Earth is constantly bombarded with protons from the solar wind, which stream outward uninterrupted until the heliopause when matter from other stars becomes more dominant. If there were, say, an antimatter star nearby, the place where its stellar wind of antiparticles met ...

1

It's possible that I do not understand this theory correctly, but it seems to me that it was disproved by experiment. Indeed, it is possible to strip an atom of its electron cloud. If the nucleus was purely an effect of the electron field, nothing would be left once the electrons are removed. This is not the case. See e.g. this post. Note that you can never ...

0

Naively, suppose you have a field F in your theory. If you look for the mass term of the field F in the Lagrangian it appears like -L $\supset$ $m^2$ $\bar{F}F$, which is invariant under the charge operator C, i.e., -$L^c$ $\supset$ $m^2$ $F^\dagger$$C^\dagger$$\gamma^0$$C$$F$ = $m^2$ $F^\dagger$$\gamma^0$$F$ =$m^2$ $\bar{F}F$ = -L, which means that the same ...

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