Suppose N independent harmonic oscillators are in equilibrium at the temperature T. The Hamiltonian and the eigenvalue of a single harmonic oscillator are given by:
H = (1)
E_n = hw_n (2)
respectively, where n is an integer satisfying n ≥ 0. Answer the following questions:
1. Find the partition function of the N-oscillator system.
2. Find the energy expectation value of the N-oscillator system and graph it as a function of temperature.
3. Find the heat capacity of the N-oscillator system and graph it as a function of temperature.
4. Discuss the difference between the temperature dependences of the heat capacities of the harmonic oscillator system and the two-level system.
5. Find the energy expectation value and heat capacity of the N-oscillator system using the classical canonical distribution.
6. Discuss the difference between the results obtained by the quantum and classical approaches.