Statistical physics is not a difficult subject, and I trust that this
will not be found a difficult book. It contains much that a number of
generations of Lancaster students have studied with me, as part of their
physics honours degree work. The lecture course was of twenty hours
duration, and I have added comparatively little to the lecture syllabus.
A pre- requisite is that the reader should have a working knowledge of
basic thermal physics (i.e. the laws of thermodynamics and their
application to simple substances). The book Thermal Physics by Colin
Finn in this series forms an ideal introduc- tion. Statistical physics
has a thousand and one different ways of approaching the same basic
results. I have chosen a rather down-to-earth and unsophisticated
approach, without I hope totally obscuring the considerable interest of
the fun- damentals. This enables applications to be introduced at an
early stage in the book. As a low-temperature physicist, I have always
found a particular interest in statistical physics, and especially in
how the absolute zero is approached. I should not, therefore, apologize
for the low-temperature bias in the topics which I have selected from
the many possibilities.