Albert
Einstein (1879–1955),
German physicist, US citizen from 1940:
formulated the
theory of relativity; awarded the 1921
Nobel prize for
physics. Although
complete understanding of his
theory of relativity requires a
knowledge of the most
exotic branches of
mathematics, these are some of its
basic points:
(1) Time is not a n
absolute. The faster a
body moves, the slower its
clock runs. A minute on Earth may
pass in fifty-nine seconds or sixty-one seconds on planets traveling at speeds
different from that of Earth.
(2) The speed of light remains
constant in all
frames of
reference. Whether you are moving toward a light
source or away from it, the light will still
reach you at the same speed (186,000 miles per
second).
(3) All
motion is
relative. Therefore, there can be no such thing as
absolute rest.
(4) Moving bodies
acquire mass as they increase in speed. The faster a
body travels, the heavier it becomes. As a
body approaches the speed of light, it adds
mass very rapidly. If it were to
reach the speed of light, its
mass would become infinite. If this were true it could be seen that no
body could ever travel faster than the speed of light. The additional
weight acquired by an accelerating
body would make penetration of the light
barrier impossible.
(5) Mass and
energy are mutually
convertible.
—HEV Approved Glossary