Neutron antiparticle anti-neutron how do they annihilate each other?

Question

it assume every particles in the universe have an antiparticles ie(proton has antiproton, electoron has positron) usually when a particle meet there counter part they annihlate each other; because they have opposite charges. Neutron also have antiparticle but neutron doesn't have any charges. How can they annihilate each other?

Answer 1

Particles do not have to have opposite charge to annihilate each other. The antineutron does exist and it does annihilate a neutron. It has no charge, but it does have the opposite magnetic moment of a neutron.

Answer 2

This kind of annihilation doesn't mean they turn into nothing. Both particles cease to exist, but the product still conserves mass, including the mass-equivalent of the energy released.

As the second reference mentions, the neutron is made of quarks (and the antineutron, of anti-quarks), which do have charge.

The 'annihilation' happens because they are antiparticles, not because they have opposite charge. That word generally isn't used of a collision between a proton and an electron.

Exactly what happens during subatomic particle interactions is a major field of study. It's the one that drove me away from physics for 40 years. I hope your curiosity survives that study!

Answer 3

Edit: Even particles that have no electrical charge, such as the neutron, have antiparticles. These have other properties with a sign (such as magnetic moment) that can be reversed.
http://science.nasa.gov/headlines/y2000/ast29may_1m.htm

http://en.wikipedia.org/wiki/Antineutron
"it is different from a neutron by being composed of antiquarks, rather than quarks. In particular, the antineutron consists of two anti-down quarks and one anti-up quark"

Glad you asked that, that's interesting.

Answer 4

Take a Physics course and do a little research on sub-atomic particles......... it will come to you ;-)