Leonard Susskind is the Felix Bloch professor
of Theoretical physics at Stanford University,
and director of the Stanford Institute for
Theoretical Physics. His research interests
include string theory, quantum field theory,
quantum statistical mechanics and quantum
cosmology. He is a member of the National
Academy of Sciences of the USA, and the American
Academy of Arts and Sciences, an associate
member of the faculty of Canada's Perimeter
Institute for Theoretical Physics, and a distinguished
professor of the Korea Institute for Advanced
Study.
Susskind is widely regarded as one of the
fathers of string theory, having, with Yoichiro
Nambu and Holger Bech Nielsen, independently
introduced the idea that particles could in
fact be states of excitation of a relativistic
string. He was the first to introduce the
idea of the string theory landscape in 2003.
Susskind was awarded the 1998 J. J. Sakurai
Prize.
Early life and education
Born Leonard Susskind to a Jewish family from
the South Bronx section of New York City,
he now resides in Palo Alto, California. He
began working as a plumber at the age of 16,
taking over from his father who had become
ill. Later, he enrolled in the City College
of New York as an engineering student, graduating
with a B.S. in physics in 1962. In an interview
in the Los Angeles Times, Susskind recalls
the moment he discussed with his father this
change in career path: "When I told my father
I wanted to be a physicist, he said: ‘Hell
no, you ain’t going to work in a drug store.’
I said no, not a pharmacist. I said: ‘Like
Einstein.’ He poked me in the chest with
a piece of plumbing pipe. ‘You ain’t going
to be no engineer’, he said. ‘You’re
going to be Einstein.’" Susskind then studied
at Cornell University under Peter A. Carruthers
where he earned his Ph.D. in 1965. He has
been married twice, first in 1960, and has
four children.
Career
Susskind was an assistant professor of physics,
then an associate professor at Yeshiva University,
after which he went for a year at the University
of Tel Aviv, returning to Yeshiva to become
a professor of physics. Since 1979 he has
been professor of physics at Stanford University,
and since 2000 has held the Felix Bloch professorship
of physics.
Susskind was awarded the 1998 J. J. Sakurai
Prize for his "pioneering contributions to
hadronic string models, lattice gauge theories,
quantum chromodynamics, and dynamical symmetry
breaking". Susskind's hallmark, according
to colleagues, has been the application of
"brilliant imagination and originality to
the theoretical study of the nature of the
elementary particles and forces that make
up the physical world".
In 2007, Susskind joined the faculty of Perimeter
Institute for Theoretical Physics in Waterloo,
Ontario, Canada, as an associate member. He
has been elected to the National Academy of
Sciences and the American Academy of Arts
and Sciences. He is also a distinguished professor
at Korea Institute for Advanced Study.
Scientific career
Susskind was one of at least three physicists
who independently discovered during or around
1970 that the Veneziano dual resonance model
of strong interactions could be described
by a quantum mechanical model of strings,
and was the first to propose the idea of the
string theory landscape. Susskind has also
made contributions in the following areas
of physics:
The independent discovery of the string theory
model of particle physics
The theory of quark confinement
The development of Hamiltonian lattice gauge
theory
The theory of scaling violations in deep inelastic
electroproduction
The theory of symmetry breaking sometimes
known as "technicolor theory"
The second, yet independent, theory of cosmological
baryogenesis
String theory of black hole entropy
The principle of black hole complementarity
The causal patch hypothesis
The holographic principle
M-theory, including development of the BFSS
matrix model
Kogut-Susskind fermions
Introduction of holographic entropy bounds
in physical cosmology
The idea of an anthropic string theory landscape
The Census Taker's Hat
Books
Susskind is the author of several popular
science books.
The Cosmic Landscape
The Cosmic Landscape: String Theory and the
Illusion of Intelligent Design is Susskind's
first popular science book, published by Little,
Brown and Company on December 12, 2005. It
is Susskind's attempt to bring his idea of
the anthropic landscape of string theory to
the general public. In the book, Susskind
describes how the string theory landscape
was an almost inevitable consequence of several
factors, one of which was Steven Weinberg's
prediction of the cosmological constant in
1987. The question addressed here is why our
universe is fine-tuned for our existence.
Susskind explains that Weinberg calculated
that if the cosmological constant was just
a little different, our universe would cease
to exist.
The Black Hole War
The Black Hole War: My Battle with Stephen
Hawking to Make the World Safe for Quantum
Mechanics is Susskind's second popular science
book, published by Little, Brown, and Company
on July 7, 2008. The book is his most famous
work and explains what he thinks would happen
to the information and matter stored in a
black hole when it evaporates. The book sparked
from a debate that started in 1981, when there
was a meeting of physicists to try to decode
some of the mysteries about how particles
of particular elemental compounds function.
During this discussion Stephen Hawking stated
that the information inside a black hole is
lost forever as the black hole evaporates.
It took 28 years for Leonard Susskind to formulate
his theory that would prove Hawking wrong.
He then published his theory in his book,
The Black Hole War. Like The Cosmic Landscape,
The Black Hole War is aimed at the lay reader.
He writes: "The real tools for understanding
the quantum universe are abstract mathematics:
infinite dimensional Hilbert spaces, projection
operators, unitary matrices and a lot of other
advanced principles that take a few years
to learn. But let's see how we do in just
a few pages."
The Theoretical Minimum book series
Susskind is currently co-authoring a series
of companion books to his lecture series The
Theoretical Minimum. The first of these, The
Theoretical Minimum: What You Need to Know
to Start Doing Physics, was published in 2013
and presents the modern formulations of classical
mechanics. The second of these, Quantum Mechanics:
The Theoretical Minimum, was published in
February 2014. The next book is expected to
focus on special relativity.
The Theoretical Minimum lecture series
Susskind teaches a series of Stanford Continuing
Studies courses about modern physics referred
to as The Theoretical Minimum. These lectures
later formed the basis for the books of the
same name. The goal of the courses is to teach
the basic but rigorous theoretical foundations
required to study certain areas of physics.
The sequence covers classical mechanics, relativity,
quantum mechanics, statistical mechanics,
and cosmology, including the physics of black
holes.
These courses are available on the The Theoretical
Minimum website, on iTunes, and on YouTube.
The courses are intended for the mathematically
literate public as well as physical science/mathematics
students. Susskind aims the courses at people
with prior exposure to algebra, calculus,
vectors, differential calculus, integrals,
and perhaps differential operators, matrices,
and linear equations. Homework and study outside
of class is otherwise unnecessary. Susskind
explains most of the mathematics used, which
form the basis of the lectures.
Smolin–Susskind debate
The Smolin-Susskind debate refers to the series
of intense postings in 2004 between Lee Smolin
and Susskind, concerning Smolin’s argument
that the "anthropic principle cannot yield
any falsifiable predictions, and therefore
cannot be a part of science." It began on
July 26, 2004, with Smolin's publication of
"Scientific alternatives to the anthropic
principle". Smolin e-mailed Susskind asking
for a comment. Having not had the chance to
read the paper, Susskind requested a summarization
of his arguments. Smolin obliged, and on July
28, 2004, Susskind responded, saying that
the logic Smolin followed "can lead to ridiculous
conclusions". The next day, Smolin responded,
saying that "If a large body of our colleagues
feels comfortable believing a theory that
cannot be proved wrong, then the progress
of science could get stuck, leading to a situation
in which false, but unfalsifiable theories
dominate the attention of our field." This
was followed by another paper by Susskind
which made a few comments about Smolin's theory
of "cosmic natural selection". The Smolin-Susskind
debate finally ended with each of them agreeing
to write a final letter which would be posted
on Edge, with three conditions attached: No
more than one letter each; Neither sees the
other's letter in advance; No changes after
the fact.
See also
Superstring theory
Quantum chromodynamics
Supersymmetry
Susskind–Glogower operator
List of theoretical physicists
Kogut–Susskind fermions
Fischler–Susskind mechanism
Boris Pregel
References
Further reading
Chown, Marcus, "Our world may be a giant hologram",
New Scientist, 15 January 2009, magazine issue
2691. "The holograms you find on credit cards
and banknotes are etched on two-dimensional
plastic films. When light bounces off them,
it recreates the appearance of a 3D image.
In the 1990s physicists Leonard Susskind and
Nobel prize winner Gerard 't Hooft suggested
that the same principle might apply to the
universe as a whole. Our everyday experience
might itself be a holographic projection of
physical processes that take place on a distant,
2D surface."
External links
Leonard Susskind's Faculty Page
Susskind's Blog: Physics for Everyone
The Theoretical Minimum website, with the
full set of free lectures
Radio Interview: Leonard Susskind discusses
his life as a physicist, string theory and
the holographic principle on The 7th Avenue
Project radio show
The Edge:
"Interview with Leonard Susskind."
"Smolin vs. Susskind: The Anthropic Principle"
Susskind and Lee Smolin debate the Anthropic
principle
Radio Interview from This Week in Science
March 14, 2006 Broadcast
"Father of String Theory Muses on the Megaverse":
Podcast
Leonard Susskind at the Internet Movie Database
Leonard Susskind: My friend Richard Feynman
on YouTube - A Ted talk
