Fusion turns hydrogen into helium, releasing massive amounts of energy in the process.
The opposite might be possible, i.e., using massive amounts of energy to split helium into hydrogen. But there’s no reason to do so, and it’s not something that happens naturally at any significant scale.
Proton emission does happen, and that’s just a positive hydrogen ion waiting to steal an electron from something else.
You could say that everything came from fusing hydrogen in the first place, and so the hydrogen being created here is just returning to its original form.
Fusion turns hydrogen into helium, releasing massive amounts of energy in the process.
The opposite might be possible, i.e., using massive amounts of energy to split helium into hydrogen. But there’s no reason to do so, and it’s not something that happens naturally at any significant scale.
It’s all about the nuclear energy binding curve.
Proton emission does happen, and that’s just a positive hydrogen ion waiting to steal an electron from something else.
You could say that everything came from fusing hydrogen in the first place, and so the hydrogen being created here is just returning to its original form.