
14
Approach to Absolute Zero
We saw in section 3.8 of chapter 3 (Nernst-Planck Theorem) that there are thermody-
namic arguments to indicate the difficulty of reaching the absolute zero temperature,
i.e 0 K. While it could not really be strictly proven using only the first and sec-
ond laws, the powerful analysis of Nernst hinted at the desirability of introducing a
separate law, usually called the Third Law of thermodynamics. In this chapter, we
explore, from a purely experimental point of view, the issue as to how close to abso-
lute zero can one get? An excellent source for further reading is Lounasmaa’s book
Experimental Principles and Methods Below ...