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6 The Fermionic Oscillator Suppose that we constructed a harmonic oscillator Hamiltonian H in terms of raising and lowering operators a+,a in the usual way, such that but now whereaa obey the anticommutation relationn (Be careful! The a+,a are operators, rather than numbers.) (a) Suppose I give you a wavefunction that solves the time-independent Schrödinger equation, i.e. such that HUn-EUn-hw (n + ) ψη. Is a+Un also a solution to the time-independent Schrödinger equation If so, what is its energy Is a Vn a solution? If so, what is its energy? (b) Since (H) E2 for a stationary state, we can again insist that there is a ground state such that Combining this with your previous answer, what are the only possible nonzero wave- functions n? (c) As with the simple harmonic oscillator, here the operator N- a+a counts numbers, .e. Nn nn Show that if, in addition to the above anticommutation relations at and a also satisfy (at,at(a,a) 0, then N2 -N (d) If the operator N counts the number of particles in a given state, explain why I called this the fermionic oscillator
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