[Marie]

Thank you for breaking it down for me! There's a lot in the terminology that gets confusing. Just to be clear on one point. You stated: When matter and antimatter collide, they are mutually annihilated, and energy is released in a burst of radiation. Matter is also created by energy in pairs as in the case where two or more photons interact to create a new fermion/antifermion pair.

So when an particle and an anti-particle collide, they cease to have mass, are transformed into massless particles and all that you have left is energy?

[Alamo-Girl]

Actually, the matter and anti-matter are mutually annihilated. What remains is the burst of energy.

But it does raise another interesting question about the beginnings of this universe that has caused some collective head-scratching: where did all the anti-matter go?

I must head out now, but I'll check back later this evening to see where the conversation is headed.

[EvilOverlord]

So when an particle and an anti-particle collide, they cease to have mass, are transformed into massless particles and all that you have left is energy?

If I recall correctly, what I learned in school is that the particle and anti-particle annihilation results in the release of a photon (a massless particle) with energy equal to the sum of the energies of the two colliding particles.

This is where E=mc² comes in. The energy of the particle is equal to it's energy of motion (kinetic energy), plus the energy of it's mass.

E = 0.5mv² + mc²

So, annihilation is really the conversion of matter to energy.

The color of the light emitted is also dependent on the energy of the particles.

Frequency (color) = E/h, where h is Planck's constant.

Typically, these are x-rays or gamma rays.