In search of gravitons, the particle that could unify physics 🍏 We know that all the other forces governed by quantum mechanics are transmitted by indivisible particles: photons for the electromagnetic force, which governs light and the basic chemistry of matter; gluons for the strong force, which sticks together protons and neutrons inside atoms; and W and Z bosons for the weak force, which enables certain particles to radioactively decay. If gravity has the same underlying theory as these for