Reduce
In high-school chemistry, you learn that the ideal gas law is
P·V =
n·R·T
These letters are drilled into my head, but I realised yesterday that I am losing my intuitive understanding of the relation. The physics version of it is
P·V =
N·kT
where N is now a dimensionless number and k is comes from the definition of T. Let ρ be our number density and the relation simplifies to
P =
ρ·kT
Pressure is density times temperature.
In the heterogeneous CS Unix environment, I may be executing emacs
from a console as “emacs -nw
” or from an icon on the desktop. Some
computers will have the emacs-color-theme package installed, others
won't. So in my .emacs file, I put the following lines:
;; from .emacs ...
(setq emacs-style-file "~/.emacs-style")
(when
(and window-system
(require 'color-theme nil t)
(file-readable-p emacs-style-file))
(progn
(load emacs-style-file)
(my-color-theme)))