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The operator $C$ replaces every particle with its antiparticle. If $C$ is a symmetry of the universe, then there is no difference between matter and antimatter. However $C$ is not a symmetry. This can be seen in that all neutrinos are left-handed, but antineutrinos are right-handed. There is also evidence that kaons and antikaons have different rates of ...


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Yes it will. Annihilation is a form of interaction which only happens between a particle and its anti-particle. You can sort of imagine it even though its not completely true I think, as destructive interference of the same particle field. Its independent of charge.


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This was answered well in the comments but I'll write it up as a proper answer. There are two main questions here: Why is there an asymmetry between matter and antimatter? given that there's an asymmetry, why did matter win out? The second question is answered rather easily. The Big Bang produced more of one of the two types and everything, from ...


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Leptons annihilate to photons. Hadrons (quarks, 99.97 mass-% of matter) emit about 50% of ${mc^2}$ annihilation energy as neutrinos. If the Big Bang plus cosmic inflation had exactly obeyed all current conservation laws, everything would have exactly cancelled to photons and neutrinos. Pair formation must be antisymmetric re conservation laws, offering no ...


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The key bit of your question is: why isn't it possible all original matter and anti-matter annihilated each other leaving all pure energy, which in turn and in time could form into matter? since other parts of it are covered by the question Parth Vader linked. Matter and anti-matter don't annihilate to produce pure energy, they annihilate to produce ...


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Almost all particles are believed to behave identically between matter and anti-matter - in fact a number of Nobel prizes were awarded for finding the few exceptions. So as far as we know anti hydrogen- anti hydrogen fusion should work just the same Anti-matter fission is probably a little way off, it's going to take quite a bit of money/time/energy to ...


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When a speedy particle collides with another particle, it loses some or all of its enormous Kinetic Energy. As energy is conserved, this Kinetic Energy is converted into particle-antiparticle pair (mass is a form of energy). They come in pair for the sake of other conservation laws. For example, if the produced pair is electron-positron, here you can see the ...


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For over forty years accelerator technology has been giving antiproton and positron beams, the easiest to create anti particles. Positrons are the simplest because once the energy of electrons is accelerated to the values over pair creation of e+e-, the the brehmstrahlung photons, gamma ray energies, will create electron positron pairs when interacting with ...


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Anti-matter is created from interactions. They are created as a way to conserve energy and other quantum numbers such as charge. One such interaction would be the $Z^0$ decay: $Z^0 → ν_e + \bar{ν_e}$ In this case lepton number is conserved. They do annihilate producing energy (usually photons, but they can produce other particle-antiparticle pairs) when ...


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The annihilation produces gamma photons, whose total energy sums up to the total energy $E_0=\sqrt{p^2 \,c^2 + m^2\,c^4}$ formerly contained in the matter / antimatter kinetic energy (the $p\,c$ term) and that "frozen" in rest mass (the $m\,c^2$ term). So energy is conserved. As for gravity, the Einstein field equations "can't tell the difference" between ...


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According to general relativity the source for spacetime curvature/gravity is the stress-energy tensor. Mass contributes rest energy $mc^2$ but it is not the only form of energy that influences gravity. Therefore it's not exactly true to say that mass causes gravity, but energy does. The photons produced during annihilation will carry energy and so they will ...


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The idea that gravity is sourced just by mass only hold in the nonrelativistic limit. In a fully relativistic treatment, which is necessary to understand any process involving particle annihilation, you must use the full stress energy tensor. This tensor includes mass, but it also includes, for instance, the energy of any photons created in the annihilation. ...


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In short, answer is no. Gravity center won't change. For example imagine electron and positron. After measuring I will get that Mass of electron and positron are same: $9.10938291 × 10^{-31}$ $kg$. So electron and positron have same mass but different charges (Charge of electron is $-1.60217657 × 10^{-19}$ $coulombs$ and charge of positron is $1.60217657 × ...


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No. The reason is very simple: If there was such an anti-matter universe, we would see very strong lines in the cosmic background radiation related to the particle masses. Those lines would come from annihilation processes like $$ e^+ e^- \rightarrow \gamma + \gamma $$ If you suggest that the anti-world is too far away to produce such a signal, I'm sorry ...


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There is no process $ \gamma \to n $ at all, nor $ \gamma \to n \bar{n}$ with an on-shell photon. The first violated multiple quantum number conservation rules and the second conservation of four-momentum. The two-photon process $$ \gamma + \gamma \to n + \bar{n} \,,$$ has allowed quantum numbers but will be exceedingly rare. It is worth noting that ...



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