Weak Interactions Weak Interactions Fundamental weak interactions occur for all fundamental particles except gluons and photons . Weak interactions involve the exchange or production of W or Z bosons .
Weak forces are very short-ranged.
In ordinary matter, their effects are negligible except in cases where they allow an effect that is otherwise forbidden. There are a number of conservation laws that are valid for strong and electromagnetic interactions, but broken by weak processes. So, despite their slow rate and short range, weak interactions play a crucial role in the make-up of the world we observe. Any process where the number of particles minus the number of antiparticles of a given quark or lepton type changes is a weak decay process and involves a W- boson . Weak decays are thus responsible for the fact that ordinary stable matter contains only up and down type quarks and electrons .