Leonard Susskind (; born June 16, 1940)
[his 60th birth anniversary was celebrated with a special symposium at Stanford University.][in Geoffrey West's introduction, he gives Suskind's current age as 74 and says his birthday was recent.] is an American
theoretical physicist
Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain, and predict natural phenomena. This is in contrast to experimental physics, which uses experi ...
, professor of
theoretical physics
Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain, and predict List of natural phenomena, natural phenomena. This is in contrast to experimental p ...
at
Stanford University
Leland Stanford Junior University, commonly referred to as Stanford University, is a Private university, private research university in Stanford, California, United States. It was founded in 1885 by railroad magnate Leland Stanford (the eighth ...
and founding director of the
Stanford Institute for Theoretical Physics. His research interests are
string theory
In physics, string theory is a theoretical framework in which the point-like particles of particle physics are replaced by one-dimensional objects called strings. String theory describes how these strings propagate through space and intera ...
,
quantum field theory
In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines Field theory (physics), field theory and the principle of relativity with ideas behind quantum mechanics. QFT is used in particle physics to construct phy ...
,
quantum statistical mechanics and
quantum cosmology.
He is a member of the US
National Academy of Sciences
The National Academy of Sciences (NAS) is a United States nonprofit, NGO, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the ...
, and the
American Academy of Arts and Sciences
The American Academy of Arts and Sciences (The Academy) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and other ...
,
[ an associate member of the faculty of ]Canada
Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
'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
In physics, string theory is a theoretical framework in which the point-like particles of particle physics are replaced by one-dimensional objects called strings. String theory describes how these strings propagate through space and intera ...
. He was the first to give a precise string-theoretic interpretation of the holographic principle in 1995 and the first to introduce the idea of the string theory landscape
In string theory, the string theory landscape (or landscape of vacua) is the collection of possible false vacua,The number of metastable vacua is not known exactly, but commonly quoted estimates are of the order 10500. See M. Douglas, "The stat ...
in 2003.
Susskind was awarded the 1998 J. J. Sakurai Prize,[ the 2018 Oskar Klein Medal, and the Dirac Medal of the ]International Centre for Theoretical Physics
The Abdus Salam International Centre for Theoretical Physics (ICTP) is a research center for physical and mathematical sciences, located in Trieste, Friuli-Venezia Giulia, Italy.
The center operates under a tripartite agreement between the Gov ...
in 2023.
Early life and education
Leonard Susskind was born to a Jewish
Jews (, , ), or the Jewish people, are an ethnoreligious group and nation, originating from the Israelites of History of ancient Israel and Judah, ancient Israel and Judah. They also traditionally adhere to Judaism. Jewish ethnicity, rel ...
family from the South Bronx
The South Bronx is an area of the Boroughs of New York City, New York City borough of the Bronx. The area comprises neighborhoods in the southern part of the Bronx, such as Concourse, Bronx, Concourse, Mott Haven, Bronx, Mott Haven, Melrose, B ...
in New York City
New York, often called New York City (NYC), is the most populous city in the United States, located at the southern tip of New York State on one of the world's largest natural harbors. The city comprises five boroughs, each coextensive w ...
. He began working as a plumber
A plumber is a tradesperson who specializes in installing and maintaining systems used for potable (drinking) water, hot-water production, sewage and drainage in plumbing systems. at the age of 16, taking over from his father who had become ill.[ Later, he enrolled in the ]City College of New York
The City College of the City University of New York (also known as the City College of New York, or simply City College or CCNY) is a Public university, public research university within the City University of New York (CUNY) system in New York ...
as an engineering student and had planned to study mechanical engineering but he changed his mind and later graduated with a B.S. in physics
Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge whi ...
in 1962. In an interview in the ''Los Angeles Times
The ''Los Angeles Times'' is an American Newspaper#Daily, daily newspaper that began publishing in Los Angeles, California, in 1881. Based in the Greater Los Angeles city of El Segundo, California, El Segundo since 2018, it is the List of new ...
'', Susskind recalls a discussion with his father that changed his 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
Cornell University is a Private university, private Ivy League research university based in Ithaca, New York, United States. The university was co-founded by American philanthropist Ezra Cornell and historian and educator Andrew Dickson W ...
under Peter A. Carruthers, where he earned his Ph.D. in 1965.
Career
Susskind was an assistant professor of physics, then an associate professor at Yeshiva University
Yeshiva University is a Private university, private Modern Orthodox Judaism, Orthodox Jewish university with four campuses in New York City. (1966–1970), after which he went for a year to the Tel Aviv University
Tel Aviv University (TAU) is a Public university, public research university in Tel Aviv, Israel. With over 30,000 students, it is the largest university in the country. Located in northwest Tel Aviv, the university is the center of teaching and ...
(1971–72), returning to Yeshiva to become a professor of physics (1970–1979). Since 1979 he has been professor of physics at Stanford University
Leland Stanford Junior University, commonly referred to as Stanford University, is a Private university, private research university in Stanford, California, United States. It was founded in 1885 by railroad magnate Leland Stanford (the eighth ...
,[ and since 2000 has held the ]Felix Bloch
Felix Bloch (; ; 23 October 1905 – 10 September 1983) was a Swiss-American physicist who shared the 1952 Nobel Prize in Physics with Edward Mills Purcell "for their development of new methods for nuclear magnetic precision measurements and di ...
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
In theoretical physics, quantum chromodynamics (QCD) is the study of the strong interaction between quarks mediated by gluons. Quarks are fundamental particles that make up composite hadrons such as the proton, neutron and pion. QCD is a type of ...
, 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
Ontario is the southernmost Provinces and territories of Canada, province of Canada. Located in Central Canada, Ontario is the Population of Canada by province and territory, country's most populous province. As of the 2021 Canadian census, it ...
, Canada, as an associate member. He has been elected to the National Academy of Sciences
The National Academy of Sciences (NAS) is a United States nonprofit, NGO, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the ...
and the American Academy of Arts and Sciences
The American Academy of Arts and Sciences (The Academy) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and other ...
. He is also a distinguished professor at Korea Institute for Advanced Study.
Scientific career
Susskind was one of at least three physicists, alongside Yoichiro Nambu and Holger Bech Nielsen, who independently discovered during or around 1970 that Gabriele Veneziano's dual resonance model of strong interactions could be described by a quantum mechanical model of oscillating strings, and was the first to propose the idea of the string theory landscape
In string theory, the string theory landscape (or landscape of vacua) is the collection of possible false vacua,The number of metastable vacua is not known exactly, but commonly quoted estimates are of the order 10500. See M. Douglas, "The stat ...
. Susskind has also made important contributions in the following areas of physics:
* The independent discovery of the string theory model of particle physics
* The theory of quark
A quark () is a type of elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nucleus, atomic nuclei ...
confinement
* The development of Hamiltonian lattice gauge theory known as Kogut–Susskind fermions
* The theory of scaling violations in deep inelastic electroproduction
* The theory of symmetry breaking sometimes known as "technicolor
Technicolor is a family of Color motion picture film, color motion picture processes. The first version, Process 1, was introduced in 1916, and improved versions followed over several decades.
Definitive Technicolor movies using three black-and ...
theory"
* The second, yet independent, theory of cosmological baryogenesis ( Andrei Sakharov's work was first, but was mostly unknown in the Western hemisphere)
* String theory of black hole
A black hole is a massive, compact astronomical object so dense that its gravity prevents anything from escaping, even light. Albert Einstein's theory of general relativity predicts that a sufficiently compact mass will form a black hole. Th ...
entropy
* The principle of black hole complementarity
* The causal patch hypothesis
* The holographic principle
* M-theory
In physics, M-theory is a theory that unifies all Consistency, consistent versions of superstring theory. Edward Witten first conjectured the existence of such a theory at a string theory conference at the University of Southern California in 1 ...
, including development of the Banks–Fischler–Shenker–Susskind matrix string model
* Introduction of holographic entropy
Entropy is a scientific concept, most commonly associated with states of disorder, randomness, or uncertainty. The term and the concept are used in diverse fields, from classical thermodynamics, where it was first recognized, to the micros ...
bounds in physical cosmology
Physical cosmology is a branch of cosmology concerned with the study of cosmological models. A cosmological model, or simply cosmology, provides a description of the largest-scale structures and dynamics of the universe and allows study of fu ...
* Cool horizons for entangled black holes
* The idea of an anthropic string theory landscape
In string theory, the string theory landscape (or landscape of vacua) is the collection of possible false vacua,The number of metastable vacua is not known exactly, but commonly quoted estimates are of the order 10500. See M. Douglas, "The stat ...
* The census taker's hat
* Most recently, application of ideas from information and computation theory, such as the complexity equals action conjecture, to the physics and thermodynamics of black holes, and holographic theories in general.
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.
/ref> 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
Stephen William Hawking (8January 194214March 2018) was an English theoretical physics, theoretical physicist, cosmologist, and author who was director of research at the Centre for Theoretical Cosmology at the University of Cambridge. Between ...
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.
/ref> 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 co-authored a series of companion books to his lecture series #The Theoretical Minimum 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 third book, ''Special Relativity and Classical Field Theory: The Theoretical Minimum'' (September 26, 2017), introduces readers to Einstein's special relativity and Maxwell's classical field theory. The fourth book in the series, ''General Relativity: The Theoretical Minimum'' was published in January 2023.
''The Theoretical Minimum'' lecture series
Susskind teaches a series of Stanford Continuing Studies courses about modern physics referred to as '' The Theoretical Minimum''. The title of the series is a clear reference to Landau
Landau (), officially Landau in der Pfalz (, ), is an autonomous (''kreisfrei'') town surrounded by the Südliche Weinstraße ("Southern Wine Route") district of southern Rhineland-Palatinate, Germany. It is a university town (since 1990), a long ...
's famous comprehensive exam called the "Theoretical Minimum" which students were expected to pass before admission to his school. ''The Theoretical Minimum'' 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
Classical mechanics is a Theoretical physics, physical theory describing the motion of objects such as projectiles, parts of Machine (mechanical), machinery, spacecraft, planets, stars, and galaxies. The development of classical mechanics inv ...
, relativity, quantum mechanics
Quantum mechanics is the fundamental physical Scientific theory, theory that describes the behavior of matter and of light; its unusual characteristics typically occur at and below the scale of atoms. Reprinted, Addison-Wesley, 1989, It is ...
, statistical mechanics
In physics, statistical mechanics is a mathematical framework that applies statistical methods and probability theory to large assemblies of microscopic entities. Sometimes called statistical physics or statistical thermodynamics, its applicati ...
, and cosmology
Cosmology () is a branch of physics and metaphysics dealing with the nature of the universe, the cosmos. The term ''cosmology'' was first used in English in 1656 in Thomas Blount's ''Glossographia'', with the meaning of "a speaking of the wo ...
, including the physics of black holes
A black hole is a massive, compact astronomical object so dense that its gravity prevents anything from escaping, even light. Albert Einstein's theory of general relativity predicts that a sufficiently compact mass will form a black hole. Th ...
.
These courses are available on ''The Theoretical Minimum'' website, on iTunes
iTunes is a media player, media library, and mobile device management (MDM) utility developed by Apple. It is used to purchase, play, download and organize digital multimedia on personal computers running the macOS and Windows operating s ...
, and on YouTube
YouTube is an American social media and online video sharing platform owned by Google. YouTube was founded on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim who were three former employees of PayPal. Headquartered in ...
. 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, and calculus. Homework and study outside of class is otherwise unnecessary. Susskind explains most of the mathematics used, which form the basis of the lectures.
Cornell Messenger Lectures
Susskind gave 3 lectures
The Birth of the Universe and the Origin of Laws of Physics
April 28-May 1, 2014 in the Cornell Messenger Lecture series which are posted on a Cornell website
A website (also written as a web site) is any web page whose content is identified by a common domain name and is published on at least one web server. Websites are typically dedicated to a particular topic or purpose, such as news, educatio ...
.
Smolin–Susskind debate
The Smolin–Susskind debate refers to the series of intense postings in 2004 between Lee Smolin
Lee Smolin (; born June 6, 1955) is an American theoretical physicist, a faculty member at the Perimeter Institute for Theoretical Physics, an adjunct professor of physics at the University of Waterloo, and a member of the graduate faculty of th ...
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 the edge.org website, with three conditions attached:
: (1) No more than one letter each.
: (2) Neither sees the other's letter in advance.
: (3) No changes after the fact.
]
Personal life
He has been married twice, first in 1960,[www.edge.org]
• ''Leonard Susskind - A Biography'' (last accessed August 12, 2007). and he has four children. Susskind is a great-grandfather.
See also
*Supersymmetry
Supersymmetry is a Theory, theoretical framework in physics that suggests the existence of a symmetry between Particle physics, particles with integer Spin (physics), spin (''bosons'') and particles with half-integer spin (''fermions''). It propo ...
* List of theoretical physicists
References
Further reading
* Chown, Marcus
"Our world may be a giant hologram"
''New Scientist
''New Scientist'' is a popular science magazine covering all aspects of science and technology. Based in London, it publishes weekly English-language editions in the United Kingdom, the United States and Australia. An editorially separate organ ...
'', 15 January 2009, 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 (Stanford University)
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'':
*
"
*
Susskind and Lee Smolin
Lee Smolin (; born June 6, 1955) is an American theoretical physicist, a faculty member at the Perimeter Institute for Theoretical Physics, an adjunct professor of physics at the University of Waterloo, and a member of the graduate faculty of th ...
debate the Anthropic principle
Radio Interview
from This Week in Science March 14, 2006 Broadcast
*"Father of String Theory Muses on the Megaverse"
Podcast
*
* - A Ted talk
*
{{DEFAULTSORT:Susskind, Leonard
1940 births
20th-century American physicists
21st-century American Jews
21st-century American physicists
American string theorists
City College of New York alumni
Cornell University alumni
Jewish American physicists
J. J. Sakurai Prize for Theoretical Particle Physics recipients
Living people
Members of the United States National Academy of Sciences
Stanford University Department of Physics faculty
The Bronx High School of Science alumni
American textbook writers