We have no idea

Bosons make up one of the two classes of particles, the other being fermions.

So far, we have some hints and some ideas about what the smallest distance in the universe might be (the Planck length). We have a pretty good catalog of twelve matter particles that so far we haven’t been able to break further apart (the Standard Model). And we have a list of three possible ways that these particles can interact (the electroweak and strong forces and gravity).