The Lorentz transform of black body radiation has been investigated from the
view point of relativistic statistical mechanics. The result shows that the
well known expression with the directional temperature can be derived based on
the inverse temperature four vector. The directional temperature in the past
literature was the result of mathematical manipulation and its physical meaning
is not clear. The inverse temperature four vector has, in contrast, clear
meaning to understand relativistic thermodynamical processes.Comment: 6 pages, no figur
