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I've recently seen that space is or could be a quantum vacuum full of particles like matter and anti-matter appearing and possibly colliding causing in theory the same effects that dark energy has. My question is could Dark energy or dark matter be a left over waste product of matter/anti-matter collisions?

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A "left over waste product" is matter, too, and it must be composed of something, of some particles allowed by the laws of physics. So labeling something as "waste" doesn't really answer any question about the identity of dark matter.

Moreover, most of antimatter has annihilated with the ordinary matter into photons. In fact, any product of the annihilation must be sufficiently neutral and in this sense similar to photons. Established science as we know it only allows photons and (much less likely to be created) gravitons as the final products of annihilation. But of course that Beyond the Standard Model theories of physics do allow new particles, like neutralinos, and they may be produced in pairs by annihilation of matter with antimatter, too. In fact, it's a part of the most standard theories of dark matter that these particles, matter, and antimatter used to be in equilibrium once and all the possible reactions were occurring at a nonzero rate.

Photons cannot be dark matter. Dark matter must be sufficiently massive to "sit" in the halos of galaxies. Photons always move by the speed of light and escape so they're no good for the explanation of the structure of galaxies. Even massive but very light particles such as neutrinos are known to be bad as an explanation of "most of dark matter" because they're still too fast (too "hot"). Most of dark matter seems to be "cold dark matter" – the particles are heavy enough so that they still move by speeds much slower than the speed of light.

I noticed that you used the term "waste product of collisions" rather than "the product of annihilation". Elastic collisions don't create any other "waste products", by definition. Inelastic collisions may produce additional particles one might call "waste products" but again, it tends to be photons or similarly neutral particles, so nothing is really changed by this change of "annihilation" to "collision".

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Thank you for answering my question. I haven't studied enough physics to do that myself. I appreciate it! – Christian A. Wojdylo Jul 23 '14 at 7:03

From my knowledge there is no waste product from a matter/anti-matter except for the extra matter or anti-matter is left over. This is because Matter/Anti-matter collisions convert the matter into energy. Which means that theoretically, you can also create new matter and antimatter out of energy. E=MC^2

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