Quarks came in a number of varieties - in fact, at first, only three were needed to explain all the hundreds of particles and the different kinds of quarks - they are called u-type, d-type, s-type.— Richard P. Feynman
Quarks came in a number of varieties - in fact, at first, only three were needed to explain all the hundreds of particles and the different kinds of quarks - they are called u-type, d-type, s-type.
