Question: why was everyone so scared of colliding two particles together?

Rob Stanley answered on 15 Jun 2016:

Are you talking about the Large Hadron Collider experiments?

A very small number of people (not the scientists involved) thought that it could lead to us creating mini black holes, which we don’t really want near Earth. They thought this because of the amount of energy that they put into the particles (they were going very fast) before they collided them. But they were wrong, and the only thing that we got was data about what the particles break down into.