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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.

6 of 164 comments (clear)

  1. Re: 1st question. by Anonymous Coward · · Score: 5, Informative

    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.

  2. Re:Problem? by viperidaenz · · Score: 5, Insightful

    What's wrong with asking how the universe works?

  3. Re:chaos? by Brett+Buck · · Score: 5, Insightful

    Quantum physics is ultimately very unsatisfying, no matter how well it works. You always have the feeling that it's a working kludge, but has to the results of us just not understanding something very basic.

  4. Re:chaos? by Brett+Buck · · Score: 5, Interesting

    That was effectively my point, there's no question that you can mathematically predict what will happen, most of the time. But this thread is about one of the examples where it doesn't appear to work, along with the various other examples mystery coefficients or mystery energy or mass being kludged in to patch things up.

        I think that this apparently "statistical" nature is a function of something very fundamental that we don't yet understand, and some day, somebody will find the reality with a slap to the forehead and a loud "D'OH!"

        Note that this has *always* been the case in physics and science in general. Phlogiston theory predicted a lot of things correctly for a long time, for a lot of people who were not morons. Then the edges started fraying, people tried various fixes to try to patch it back together, until someone came along with a conceptual advance, then the old way seems ridiculous and obviously wrong. We are in the "fraying edges" point of the cycle (like the late 1800s).

  5. CP Violation by Roger+W+Moore · · Score: 5, Informative

    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.

  6. Re:1st question. by fahrbot-bot · · Score: 5, Funny

    Very, very carefully.

    If all the antimatter ever made by humans were annihilated at once, the energy produced would be just about enough to make a cup of tea.

    Or, at the very least, something almost, but not quite entirely unlike tea.

    --
    It must have been something you assimilated. . . .