What is su 2?

SU(2), also known as the special unitary group of degree 2, is a mathematical group consisting of 2x2 unitary matrices with determinant equal to 1. It is a fundamental group in physics, particularly in the fields of quantum mechanics and particle physics, where it plays a crucial role in the theory of elementary particles, gauge symmetry and the electroweak interaction. The Lie algebra (the vector space of matrices that satisfy certain conditions) associated with SU(2) is widely used in quantum mechanics and its applications. SU(2) has many applications in the study of atomic, molecular and subatomic physics, as well as in the analysis of the spin of particles. SU(2) is also closely related to the rotation group SO(3), as both groups have the same Lie algebra.