The new, twenty-third edition of the freely
downloadable physics textbook is available on

http://www.motionmountain.net

Over 1500 pages in five volumes show that physics is as much
fun as anything else you may think of. The adventure leads
through the whole of modern physics and promises
to be fascinating and challenging on every page.

The twenty-third edition includes new films on the
relativistic effects due to aberration and accelerated
motion and new films on the motion of wave functions in
quantum theory. The text now tells how yellow light improves
tomato sales and pink light reduces crime, it presents
the still unexplained experiences of apnoe divers, it explains
why wearing sunglasses can transform humans into apes, it
tells about the recently discovered natural quasicrystals,
it explains nerve pulses as a mixture of sound and current,
it describes the wake behind ducks, swans and ships, it
explains why ultrasound imaging is not safe for a foetus,
it adds the relativistic circular train puzzle, it explains
how to prove the invariance of the speed of light by
looking at the sky, it gives details about the solar
spectrum, it presents the ``floating bed'' puzzle,
it tells about a measured version of the Unruh effect
called the Sokolov-Ternov effect, it explains how to
measure the power of the with closed eyes, it gives
the ideal shape of skateboard half-pipes, and it estimates
the total length of all capillaries in the human body.

A beautiful French translation by Benoit Clenet of most
of the text is also available. A German, an Italian and a
Spanish translation of the section of special relativity
are also available.

Enjoy the reading!

Christoph Schiller