DIRECTORY 337
citizen in 1939. He was awarded a
Nobel Prize in Physics for his work
on quantum mechanics in 1954.
See also: Erwin Schrödinger
226–33 ■ Werner Heisenberg
234–35 ■ Paul Dirac 246–47 ■
J. Robert Oppenheimer 260–65NIELS BOHR
1885–1962One of the leading early theorists
of quantum physics, Dane Niels
Bohr’s first major contribution to
the quantum revolution was to
refine Ernest Rutherford’s model of
the atom. In 1913, Bohr added the
idea that electrons occupy specific
quantized orbits around the
nucleus. In 1927, Bohr collaborated
with Werner Heisenberg to
formulate an explanation of
quantum phenomena that came
to be known as the Copenhagen
interpretation. A concept central
to this interpretation was Bohr’s
complementarity principle, which
states that a physical phenomenon,
such as the behavior of a photon or
an electron, may express itself
differently depending on the
experimental set-up used to
observe it.
See also: Ernest Rutherford
206–13 ■ Erwin Schrödinger
226–33 ■ Werner Heisenberg
234–35 ■ Paul Dirac 246–47GEORGE EMIL PALADE
1912–2008Romanian cell biologist George
Emil Palade graduated in medicine
from the University of Bucharest
in 1940. He emigrated to the US
at the end of World War II, and did
his most important work at the
Rockefeller Institute in New York.Palade developed new techniques
for tissue preparation that allowed
him to examine the structure of
cells under an electron microscope,
and this work greatly advanced
the understanding of cellular
organization. His most important
achievement was the discovery in
the 1950s of ribosomes—bodies
inside cells that were previously
thought to be fragments of
mitochondria, but are in fact the
primary sites of protein synthesis,
linking together amino acids in a
specific sequence.
See also: James Watson and
Francis Crick 276–83 ■
Lynn Margulis 300–01DAVID BOHM
1917–1992American theoretical physicist
David Bohm advanced an
unconventional interpretation of
quantum mechanics. He postulated
the existence of an “implicate
order” to the universe that is a more
fundamental order of reality than
the phenomena we experience as
time, space, and consciousness.
He wrote: “an entirely different sort
of basic connection of elements is
possible, from which our ordinary
notions of space and time, along
with those of separately existent
material particles, are abstracted
as forms derived from the deeper
order.” Bohm worked with Albert
Einstein at Princeton University
until the early 1950s, when his
Marxist political views led him to
leave the US—first for Brazil and
later London, where he was a
professor of physics at Birkbeck
College from 1961.
See also: Erwin Schrödinger
226–33 ■ Hugh Everett III 284–85 ■
Gabriele Veneziano 308–13EUGÈNE BLOCH
1878–1944
French physicist Eugène Bloch
conducted studies in spectroscopy,
and produced evidence in
support of Albert Einstein’s
interpretation of the photoelectric
effect using the idea of quantized
light. During World War I,
Bloch worked on military
communications, developing the
first electronic amplifiers for radio
receivers. In 1940, he fell victim to
the anti-Jewish laws of the Vichy
government and was dismissed
from his post as a professor of
physics at the University of Paris.
He fled to unoccupied southern
France, but was captured by the
Gestapo in 1944 and deported to
Auschwitz, where he was killed.
See also: Albert Einstein 214–21
MAX BORN
1882–1970
In the 1920s, German physicist
Max Born, while professor
of experimental physics at
the University of Göttingen,
collaborated with Werner
Heisenberg and Pascual Jordan
to formulate matrix mechanics,
a mathematical means of dealing
with quantum mechanics. When
Erwin Schrödinger formulated his
wave function equation to describe
the same thing, Born was the first
to suggest the real-world meaning
of Schrödinger’s mathematics—it
described the probability of finding
a particle at a specific point on the
space-time continuum. In 1933,
Born and his family left Germany
when the Nazis dismissed Jews
from academic posts. He settled
in Britain, becoming a British