In the lab, we could not see or physically describe the mathematical objects that we called quarks, which we suspected were the key to unlocking the dynamics of the strong force that binds together the clump of protons and neutrons… — David Gross Copy Share Image
The mathematics clearly called for a set of underlying elementary objects-at that time we needed three types of them-elementary objects that could be combined three at a time in different ways to make all the heavy particles we knew. ...… — Murray Gell-Mann Copy Share Image
