So what happened to it? Using the LHCb experiment at CERN to study the difference between matter and antimatter, we have discovered a new way that this difference can appear. At first, it was not clear if this was just a mathematical quirk or a description of a real particle. But in Carl Anderson discovered an antimatter partner to the electron — the positron — while studying cosmic rays that rain down on Earth from space. Over the next few decades physicists found that all matter particles have antimatter partners.
Scientists believe that in the very hot and dense state shortly after the Big Bang, there must have been processes that gave preference to matter over antimatter. This created a small surplus of matter, and as the universe cooled, all the antimatter was destroyed, or annihilated, by an equal amount of matter, leaving a tiny surplus of matter.
And it is this surplus that makes up everything we see in the universe today. Exactly what processes caused the surplus is unclear, and physicists have been on the lookout for decades. The behaviour of quarks, which are the fundamental building blocks of matter along with leptons, can shed light on the difference between matter and antimatter. The up and down quarks are what make up the protons and neutrons in the nuclei of ordinary matter, and the other quarks can be produced by high-energy processes — for instance by colliding particles in accelerators such as the Large Hadron Collider at CERN.
Particles consisting of a quark and an anti-quark are called mesons, and there are four neutral mesons B 0 S , B 0 , D 0 and K 0 that exhibit a fascinating behaviour. Don't expect any antimatter bombs. Antimatter is now frequently used in medicine in positron emission tomography PET scans. Positrons are anti-electrons. Mike W. Quote:"If you put enough energy together in one place, you can produce a particle and an antiparticle pair together.
Or are there any necessary cicumstances to 'produce' an electron-positron-pair or an proton-antiproton-pair? What do you think, where's all that "antimatter" in our world? Probably most of them annihilated within the 'first second', but the rest of matter formed our "today's Universe". So is it possible that there is somewhere else our anti-universe, that looks absolutely the same as ours? Good questions Dani. The pair production process occurs during collisions between two other particles.
The first requirement in pair production is that all of the basic conservation laws must be obeyed: energy, momentum, angular momentum, charge, lepton number, strangeness, etc.
Other than that, anything goes. The different rates of pair production can depend on available kinetic energy of the final particles, phase space considerations and the relative coupling strengths of the possible interactions. It's a crap shoot, to use the vernacular. However the relative probabilities can be calculated.
As you point out there seems to be more matter around than antimatter: why? This is a profound question and is one of the puzzling questions of today. The necessary conditions for matter-antimatter asymmetry was first pointed out by the Nobel Prize winner Andrei Sakharov: see.
It could be there is a neighboring universe that has the asymmetry going the other way. We don't know. Great answers. But there's just one thing I'm still confused with. Apparently we can use the energy produced from antimatter and convert it for use. What could we use this energy for? And how could we get energy from something that will be destroyed if it comes into contact with any form of matter? When antimatter annihilates with ordinary matter it mainly produces photons and other particles like mesons which in turn decay into more photons, electrons, etc.
These secondary particles will be absorbed by surrounding matter and the net result is a heating of the absorbing material. In principle one could use a beam of antimatter to heat up water to make steam and run a turbine to generate electricity.
However from an economic point of view it won't pay because the cost of generating the antimatter far exceeds the payback by many orders of magnitude. Gravitation is Pushing. See please the New Paradigm by Dr. Lucy Haye PH. OK, but what is gravitation pushing? The New Paradigm? The answer may lie at CERN, where scientists create antimatter by smashing protons together in the Large Hadron Collider LHC , the world's biggest, most powerful particular accelerator. The more energy the LHC produces, the more massive are the particles--and antiparticles--formed during collision.
It is in the debris of these collisions that scientists such as Ivan Polyakov, a postdoc in Syracuse's HEP group, hunt for particle ingredients. HEP is renowned for its pioneering research into quarks--elementary particles that are the building blocks of matter. Each pair has a corresponding mass and fractional electronic charge. Despite its relatively high mass, a charmed quark lives a fleeting existence before decaying into something more stable.
Recently, HEP studied two versions of the same particle. One version contained a charmed quark and an antimatter version of an up quark, called the anti-up quark.
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