The weak interaction and fusion?

[misogynisticfeminist]

I've heard that the weak interaction actually governs fusion between hydrogen especially in the sun, how does this actually works?

[zefram_c]

Take a look here: http://www.wordiq.com/definition/Proton-proton_chain
The proton-proton chain is by far the predominant mechanism. The first step - the formation of deuteron - is governed by weak interactions, and is also the slowest due to the high energy barrier involved.