What's the Heat of Formation of Proton, Neutron and Electron?

[CutterMcCool]

I'm thinking about the thermodynamics of electron capture:

p + e --- n + v(e) + energy

(That is, proton absorbs electron to give neutron, electron neutrino and energetic photons.)

This is thermodynamically disfavored given the substantial energy barrier to fusion to a neutron (analogous to stellar fusion of hydrogen to helium) so it must involve a tremendous release of energy (increase in entropy) when it occurs.

Ultimately I'm looking to calculate the increase in universal entropy that the entropy change in this system provides.

[mathman]

The reaction your describing has energy going the wrong way. A neutron decays into a proton, an electron, and neutrino. In order to go the other way you have to add energy.

[CutterMcCool]

Yes that's correct, energy must be input to initiate this. But (disordered) energy also comes out on the backside after energy is put in.