Symmetries and Quark Model

This lecture explores the role of symmetries in particle physics, focusing on the quark model to derive hadron wave-functions and introduce abstract concepts like color and QCD. It covers the SU(2) and SU(3) symmetry groups, crucial in particle physics, and explains why hadrons exist as mesons, baryons, or antibaryons. The conservation laws resulting from symmetries are discussed, leading to the concept of isospin and its properties. The lecture also delves into the flavor symmetry of the strong interaction, showing how quark flavors are treated equally. By combining quarks, the lecture illustrates how isospin and symmetry properties play a key role in defining baryon wave-functions.