Why, then, do we live in a universe dominated by matter? Many theoretical answers have been proposed, with experimental tests scheduled to be carried out at the particle physics lab CERN near Geneva, Switzerland.ġ932 Carl Anderson discovers the position in cosmic raysġ964 Discovery of CP violation, an asymmetry in processes producing matter and antimatter, in processes involving strange quarksġ982 The Low Energy Antiproton Ring, LEAR, came into operation at CERN with the aim of manufacturing antihydrogenġ995 LEAR makes the first atoms of antihydrogen – but they’re travelling too fast to studyĢ000 CERN’s Antimatter Factory starts up, using LEAR’s successor, the Antiproton DeceleratorĢ001 Discovery of CP violation in processes involving bottom quarksĢ008 The Large Hadron Collider starts up, with the dedicated LHCb experiment looking at rare antimatter processesĢ014 The ASACUSA experiment observes antihydrogen atoms in a “field-free region” needed to make accurate measurementsĢ017 The BASE experiment at CERN’s Antimatter Factory measures the antiproton’s magnetic moment to an accuracy of 1.5 parts per billion, better than the equivalent proton measurement. According to the best models we have of the early universe, the big bang should have produced equal quantities of matter and antimatter. One of the great mysteries surrounding antimatter is why there isn’t more of it around. These particles don’t hang around for long, though, as they annihilate upon contact with their first electron. Bananas and brazil nuts are also regular emitters. We actually emit positrons ourselves, thanks largely to the radioactive potassium-40 in our bodies. ![]() Some antimatter particles are actually fairly common, as positrons are produced in the beta decays of certain radioactive elements. In all cases, if an antiparticle were to meet its opposite number, then the two would annihilate in a blast of light and energy. Force-transmitting particles, for example, such as photons and the Higgs boson, are often their own antiparticles, while debate rages about whether the same applies to neutrinos and antineutrinos. Some particles have no antimatter equivalent. So whereas an ordinary electron has a mass of 9.1×10^-31kg and a negative electrical charge of -1, its antimatter version – the positron – has the same mass but a positive charge of +1. ![]() But many of these particles have an antimatter equivalent: a particle identical in every respect, but with an opposite charge. ![]() As far as everyday life goes anti-water would interact with other anti-matter in exactly the same way as water interacts with matter.The world we live in is overwhelmingly made up of particles of matter. There are a few differences due to a phenomenon called CP violation 1 but this is only observable in colliders like the LHC, and even then it isn't a large effect. However we can be very confident about the behaviour of anti-matter because matter and anti-matter are related by a symmetry called CP-Symmetry that is theoretically well understood and experimentally well tested. We have never made anti-water, or even anti-oxygen, and it will be a long time before we achieve such a feat. Even looking in greater detail the electronic and indeed nuclear spectra would be identical to water. The anti-water would have the same density, boiling point, ability to dissolve anti-salt and so on. ![]() The anti-Dirk could drink an anti-glass of anti-water in exactly the same you drink a glass of water. If we could magically change all matter to anti-matter by waving a magic wand then it would make almost no difference. Anti-matter is a lot less exciting than you probably think.
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