# If antimatter and matter become pure energy when they combine and an

If antimatter and matter become pure energy when they combine and an electron has an antiparticle (a positron) what is the energy that comes from their combination? I thought electrons were made of energy.
Thanks

SpaceTiger
Staff Emeritus
Gold Member
bmurphy12345 said:
If antimatter and matter become pure energy when they combine and an electron has an antiparticle (a positron) what is the energy that comes from their combination? I thought electrons were made of energy.

I'm not sure I entirely understand your question, but when electrons and positrons collide (or annihilate), they create photons. Specifically, since the total energy of electron+positron >~ MeV, they'll form gamma-ray photons. It's just a matter of converting different forms of energy (mass energy+kinetic energy -> photon energy).

dextercioby
Homework Helper
In technical language,total 4 momentum in a Feynman diagram is zero.

Daniel.

if matter is energy can it be converted into antimatter?

I guess, when the condition is fit, then what will happen is that the energy form a matter and it's antimatter.

bmurphy12345 said:
if matter is energy can it be converted into antimatter?

As long as energy and momentum (and charge and all that) are conserved, almost anything can happen.

Staff Emeritus
Gold Member
Dearly Missed
masudr said:
As long as energy and momentum (and charge and all that) are conserved, almost anything can happen.

And charge, and CPT, and maybe some other symmetries.

And charge, and CPT, and maybe some other symmetries.

I mentioned charge, and the "all that" stood for the stuff you say. As far as we know, anyway.

ZapperZ
Staff Emeritus
For those who may not realize, or missed it, what SelfAdjoint and Masudr are trying to convey is that there are MORE consideration to be taken into account than just "energy goes to matter". One needs to consider a number of conservation laws for something to occur. You just cannot take energy and BAM, convert it into matter. Pair-production, for example, where high energy photons converts into a matter-antimatter pair can only occur in the vacinity of "massive" objects due to conservation of momentum issues.

There are specific rules and laws for things to occur in physics in which there are not only qualitative, but also quantative restrictions. Knowing just ONE of the rules does not tell you if something is possible or not.

Zz.