A spin in a constant magnetic field B is described by the Hamiltonian H = -γS · B, where S are the quantum operators and γ is the gyromagnetic ratio (the ratio of the magnetic moment to the spin). For a spin-1/2 system, with a two-dimensional space of states, the spin operators are proportional to the Pauli matrices, S = ℏσ. If the magnetic field B points in the x direction:
(a) Find the eigenstates and corresponding energy eigenvalues of the Hamiltonian.



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