Galileo, Eotvos and the Fifth Force
http://commons.wikimedia.org/wiki/File:Leaning_tower_of_pisa_4.png
Most people have heard the story about Galileo’s fun
experiments at the Tower of Pisa, designed to show that, contrary to the
prevailing Aristotlean view, all bodies have the same free-fall acceleration (if
drag forces can be neglected) so that the graviational mass
mG and the
inertial mass
mI of an object are equal. The story is probably untrue. But
(with pendulum experiments) Galileo is generally credited with having shown that
This kind of experiment has subsequently been repeated, many times.
Most famously in 1889 Eotvos showed that
In the last decade, however, Eotvos’ results have been reexamined. Some claim to
have found evidence that the equality
mI=mG is not (quite) correct...and
thence evidence of a new ‘fundamental’ force, called (imaginatively) the ‘Fifth Force’.
The ‘evidence’ does not appear to have withstood closer scrutiny.