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Physicists Investigate Why Matter and Antimatter Are Not Mirror Images (economist.com)
An anonymous reader shares a report: As mismatches go, it's a big one. When physicists bring the Standard Model of particle physics and Einstein's general theory of relativity together they get a clear prediction. In the very early universe, equal amounts of matter and antimatter should have come into being. Since the one famously annihilates the other, the result should be a universe full of radiation, but without the stars, planets and nebulae that make up galaxies. Yet stars, planets and nebulae do exist. The inference is that matter and antimatter are not quite as equal and opposite as the models predict.
This problem has troubled physics for the past half-century, but it may now be approaching resolution. At CERN, a particle-physics laboratory near Geneva, three teams of researchers are applying different methods to answer the same question: does antimatter fall down, or up? Relativity predicts "down", just like matter. If it falls up, that could hint at a difference between the two that allowed a matter-dominated universe to form.
This problem has troubled physics for the past half-century, but it may now be approaching resolution. At CERN, a particle-physics laboratory near Geneva, three teams of researchers are applying different methods to answer the same question: does antimatter fall down, or up? Relativity predicts "down", just like matter. If it falls up, that could hint at a difference between the two that allowed a matter-dominated universe to form.
Various ways of creating antimatter have been used in physics. One is to get a photon (particle of light) to convert into an electron and positron (antimatter equivalent of an electron). Another is to smash a proton into a necleus and create various particles of matter and antimatter and filter them by charge and momentum. If you want learn about antimatter in general, Don Lincoln has some introductory videos on YouTube.
This problem has troubled physics for the past half-century...
This "problem" is why we are here. How about not calling the existence of the universe a "problem"?
Different kind of problem. (from Google):
Physics : Mathematics
- an inquiry starting from given conditions to investigate or demonstrate a fact, result, or law.
It must have been something you assimilated. . . .
There is a retired scientist called Jean-Pierre Petit that has some ideas about this question (spoil: this antimater will fall down). This is the Janus cosmological model
. I do not know if he is right or wrong, but the videos are worth a look
We've never observed Hawking radiation from a black hole. An analog of Hawking radiation has been observed from model experiments, e.g. where a medium has an area that is supersonic so sound waves can't propagate back out of that region.
CERN experiments to test the free-fall of antiatoms
https://cerncourier.com/does-a...
Anti-neutrons are definitely different from neutrons. Neutrons are made up of 3 quarks, two down and one up whereas anti-neutrons are made of three anti-quarks, two anti-down and one anti-up.
This is because neutrons are made of fermions which have different particle and antiparticle states. Only bosons, like the photon, have the same particle and antiparticle states.
Couldn't this be a case of a butterfly flapped its wings...
Short answer: no, assuming you mean some random fluctuation in the early Universe. For the excess of matter over anti-matter in the early universe to be due to such a random fluctuation, there would have to be some process that allows more matter than anti-matter to be created and we have not seen anything that does this yet.
However, we have seen a bias between matter and antimatter in decays of certain types of particles made of quarks and anti-quarks bound together. While this is not enough to create more matter than anti-matter if the same effect exists in the oscillations of neutrinos then there may just be enough to explain the excess of matter over antimatter. However, this would still not be a random fluctuation but rather that the universe has an inbuilt bias in the laws of physics which favours matter over antimatter.
As an interesting aside this difference, called CP violation, is also the only physics we know of that requires three generations of quarks and leptons to exist. If there were only two generations we could not have a difference at least via this mechanism.