For 3 good reasons:
under the alps mountain in europe between switzerland and france it's called the large hadron collider and its a massive circular tunnel tiny particles are shot at high speed's to see what happens when they collide.
albert einstein studied light gravity speed and time and for being the first one to stick his tongue at a photographer.
that smaller items drop quicker then bigger items
yes just keep on asking questions like wy is milk white and someday you will be the future scientist and will know the answer?.