Showing posts with label antimatter. Show all posts
Showing posts with label antimatter. Show all posts

Thursday, April 28, 2022

Matter and antimatter. Why are we here?

The matter making the solar system, the Earth, all living beings and ourselves, is made up almost entirely of atoms which, in turn, are based on three elementary particles: protons, neutrons and electrons. For each of these particles, as well as for many others, not usually part of atoms, there is an antiparticle. Therefore, there could be antimatter antiatoms, made of antiprotons, antineutrons, and antielectrons (positrons).

An interesting property of matter and antimatter is that they cannot be together. As soon as they come into contact, they completely disintegrate, transforming into energy. Everything suggests that our galaxy (the Milky Way) is made up almost exclusively of matter. There is also some antimatter, in the form of antiparticle clouds, outside the galaxy, close to it and attracted by its gravity, but in such a small quantity, compared to the mass of the galaxy, that for practical purposes it can be ignored. It has also been said that there could be some (but very few) anti-stars.

Thursday, March 22, 2018

Can there be life without the weak interaction?

Beta and neutron decay
On January 30, 2018, the Science News magazine commented on an article recently published in arXiv which states that in a universe without the weak interaction, life would still be possible. When I read the Science News article, I immediately thought of an objection that could ruin both the thesis of the original article and its popularization. The first thing I did was looking up the original article, to see if my objection was mentioned or denied, but there was not a word about it. Next I detailed my objection in a comment in the web version of the Science News article, but so far no one has answered me. However, I think the objection is quite strong, and unless I am answered satisfactorily, in my opinion these articles are discredited.
According to the standard cosmological model and the standard model of particle physics, there are four fundamental interactions or forces in the universe: gravitation, electromagnetic interaction, and the strong and weak interactions, which regulate the work of atoms and elementary particles. In particular, the weak interaction affects all the elementary particles: leptons and hadrons, unlike the strong interaction, which affects only hadrons.