How does the Big Bang Theory explain the creation of matter from energy?

[Chalnoth]

Have looked at particle decay on wiki. No mention of quarks.
Why does a neutron decay when on its own and not when part of an atomic neucleus?

Because a proton, electron, and neutrino/anti-neutrino pair is a lower-energy state than a neutron.

 

[Mark M]

Lots of interesting disscussion but it still leaves me no further forward.
Mass and energy are equivalent. Energy as I understand it is massless ripples through spacetime. How do you get from massless ripples to say an electron. If the BB theory is correct then all that could be there to start is massless energy.

Particle pair production. Particles of radiation, called photons, can emit a particle, and an anti-particle. Through the processes of baryogenesis and leptogenesis, matter gained a slight edge over anti-matter resulting in a stew of particles.