quantum phys

Problem 5.13 Consider a particle with spin quantum number s=1. Ignore all spatial degrees of freedom and assume that the particle is subject to an external magnetic field B=x^B. The Hamiltonian operator of the system is H=gBS. (a) Obtain explicitly the spin matrices in the basis of the S2,Sz eigenstates, s,ms. (b) If the particle is initially (at t=0 ) in the state 11, find the evolved state of the particle at times t>0. (c) What is the probability of finding the particle in the state 11