Scientific Contributions
- The independent discovery of the string theory model of particle physics
- The theory of quark 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 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
- Introduction of holographic entropy bounds in physical cosmology
- The idea of an anthropic string theory landscape
- The Census Taker's Hat
Black Hole Complementarity
- Stephen Hawking - information is lost in an evaporating black hole once it passes through the event horizon and is inevitably destroyed at the singularity
- Can turn pure quantum states into mixed states, some physicists have wondered if a complete theory of quantum gravity might be able to conserve information with a unitary time evolution.
- How can this be possible if information cannot escape the event horizon without traveling faster than light?
- Ruled out Hawking radiation as the carrier of the missing information
- It also appears as if information cannot be "reflected" at the event horizon as there is nothing special about it locally
- Leonard Susskind proposed a radical resolution - information is both reflected at the event horizon and passes through the event horizon and cannot escape, with the catch being no observer can confirm both stories simultaneously
- This isn't to say there are two copies of the information lying about — one at or just outside the horizon, and the other inside the black hole — as that would violate the no cloning theorem
- Instead, an observer can only detect the information at the horizon itself, or inside, but never both simultaneously
- Complementarity is a feature of the quantum mechanics of noncommuting observables, and Susskind proposed that both stories are complementary in the quantum sense
String Theory
Awards
- Pomeranchuk Prize (2008)
- American Institute of Physics' Science Writing Award
- Sakurai Prize (1998)
- Boris Pregel Award
- New York Academy of Sciences (1975)
Career
- "Solution" to unified field theory issue
- Treats point particles as strings, one dimensional objects
- Describes how these strings propagate through space and interact with each other
- One of the many vibrational states of the string corresponds to the graviton, a quantum mechanical particle that carries gravitational force
- Theory of quantum gravity
- One of the leading theories, no real way to confirm or deny
- Started as an assistant professor of physics at various universities
- Has been professor of physics at Stanford University since 1979,
- 1998 J. J. Sakurai Prize for his "pioneering contributions to hadronic string models, lattice gauge theories, quantum chromodynamics, and dynamical symmetry breaking".
- Elected to the National Academy of Sciences and the American Academy of Arts and Sciences
- Professor at Korea Institute for Advanced Study
Fame
- Well known in academia and physics research community
- Not as famous as he should be, relatively quiet personality
- Thinker > Talker
Publications
- The Cosmic Landscape
- brings String theory to public eye
- The Black Hole War
- explains his efforts to resolve the information theory paradox on evaporating black holes
- The Theoretical Minimum book series
- More education based texts
- Lecture series
- Black Hole Complementarity and the Harlow-Hayden Conjecture
- New Concepts for Old Black Holes
Early Life
Leonard Susskind
- Grew up in the South Bronx of NYC
- Now lives in Palo Alto, California.
- First worked as a plumber
- Attended City College of New York as an engineering student
- Graduating with a B.S. in physics in 1962
- Studied at Cornell University under Peter A. Carruthers where he earned his Ph.D. in 1965.
- Married twice, first in 1960, and has four children.
- Born in 1940
- Professor of theoretical physics at Stanford University,
- Director of the Stanford Institute for Theoretical Physics
- "Father" of String Theory
Smolin–Susskind Debate
- close with Richard Feynman
- great-grandfather
- Lee Smolin attacks Susskind's "anthropic principle" saying that it cannot yield any falsifiable predictions, and therefore cannot be a part of science
- Susskind responded, saying that the logic Smolin followed "can lead to ridiculous conclusions"
- 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."
- Susskind comments on Smolin's theory of Cosmic Natural Selection
- Ended debate with a final letter
Bibliography
Leonard Susskind
- http://theoreticalminimum.com/biography
- https://physics.stanford.edu/people/faculty/leonard-susskind
- https://www.ted.com/talks/leonard_susskind_my_friend_richard_feynman
- http://www.telegraph.co.uk/culture/books/10654762/The-man-who-proved-Stephen-Hawking-wrong.html
American Physicist