Thermodynamics, Statistical Physics, and Quantum Mechanics

218 SOLUTIONS

Using the equation for an ideal gas, in (S.4.94.12), we obtain

Third solution: Use the Poisson distribution, which does not require that

the fluctuations be small:

The average square number of particles is

Thus we recover (S.4.94.8) again:

c) Again we will use (S.4.94.1):

Since the gas is strongly degenerate, we can use and
(see Problem 4.66):

Then