Hermann Nicolai

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Hermann Nicolai (born 11 July 1952 in Friedberg) is a German theoretical physicist and director emeritus at the Max Planck Institute for Gravitational Physics in Potsdam-Golm.

Contents

Education and career

At Karlsruhe Institute of Technology, Hermann Nicolai, beginning in 1971, studied physics and mathematics with a Diplom in 1975 with a doctorate in 1978 under the supervision of Julius Wess. [1] At Heidelberg University, Nicolai was from 1978 to 1979 an assistant in theoretical physics. From 1979 to 1986, he worked at CERN in Geneva as a staff member in the theory department. In 1983 he received his habilitation at Heidelberg University. He was a professor (with civil service grade C3) of theoretical physics at Karlsruhe Institute of Technology from 1986 to 1988 and from 1988 to 1997 a professor (with civil service grade C4) of theoretical physics at the University of Hamburg. At the Max Planck Institute for Gravitational Physics, Nicolai was head of the department "Quantum Gravity and Unified Field Theories" and a director from 1997 to 2020, when he retired as director emeritus. [2]

He was a member of the editorial board of Communications in Mathematical Physics from 1993 to 1995. Then, from 1998 to 2003 the editor-in-chief of the journal Classical and Quantum Gravity , and from 2006 to 2011 the editor-in-chief of the journal General Relativity and Gravitation . [2]

In 1991, Nicolai received the Otto-Klung-Award (now called the Klung Wilhelmy Science Award), in 2010 the Albert Einstein Medal, and in 2013 the Gay-Lussac-Humboldt Prize. He was appointed an honorary professor at the Humboldt University of Berlin and in 2005 at the University of Hannover. [2]

Research

In the mid 1980s, Nicolai and Bernard de Wit developed the "N = 8 supergravity theory", [3] which arises from the dimensional reduction of the maximally supersymmetrical eleven-dimensional supergravity to four space-time dimensions (d = 4) and for which, from many plausible viewpoints, a maximal supersymmetry has a supergravity theory with a graviton and no particle with a spin greater than 2.

In the 2000s, Nicolai and colleagues investigated the behavior of gravitational equations close to a gravitational singularity such as the Big Bang; [4] these investigation lead to models with chaotic dynamical billiards, in the case of classical general relativity theory in three dimensions. In the case of eleven-dimensional supergravity, these investigations to ten-dimensional "cosmological billiards", and the infinite-dimensional hyperbolic Kac Moody algebra appears as a symmetry. contains the largest finite-dimensional exceptional semi-simple complex Lie algebra , which has been studied as a candidate for a grand unified theory (GUT]. [5] Nicolai proposed a purely algebraic description of the universe in cosmological space-time regions near the singularity (within the Planck time) using the -symmetry, whereby the space-time dimensions result as an emergent phenomenon. [6] [7]

Nicolai has also done research on a special role for in M-Theory.

He and de Wit also constructed maximally gauged (N = 16) supergravity theories in three dimensions and their symmetries. [8] Furthermore, Nicolai and colleagues examined generalizations of the variables of loop quantum gravity to supergravity / string theory.

Selected publications

In addition to the publications cited in the footnotes:

See also

Related Research Articles

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References

  1. "Hermann Nicolai". Physics Tree.
  2. 1 2 3 "Professor Dr. Dr. h. c. Hermann Nicolai, Curriculum Vitae". Max Planck Institute for Gravitational Physics (Albert Einstein Institute).
  3. De Wit, B.; Nicolai, H. (1982). "N = 8 supergravity". Nuclear Physics B. 208 (2): 323–364. Bibcode:1982NuPhB.208..323D. doi:10.1016/0550-3213(82)90120-1. (over 700 citations)
  4. Nicolai and his colleagues investigated the theoretical implications of the BKL singularity introduced by Belinski, Khalatnikov, and Lifschitz in general relativity
  5. Damour, Thibault; Henneaux, Marc (2001). "E10, BE10 and Arithmetical Chaos in Superstring Cosmology". Physical Review Letters. 86 (21): 4749–4752. arXiv: hep-th/0012172 . Bibcode:2001PhRvL..86.4749D. doi:10.1103/PhysRevLett.86.4749. PMID   11384339. S2CID   40345084. Thibault Damour and Marc Henneaux were the first to publish the specific theory of arithmetical chaos in superstring cosmology providing the basis for such research.
  6. Kleinschmidt, Axel; Koehn, Michael; Nicolai, Hermann (2009). "Supersymmetric quantum cosmological billiards". Physical Review D. 80 (6): 061701. arXiv: 0907.3048 . Bibcode:2009PhRvD..80f1701K. doi:10.1103/PhysRevD.80.061701. S2CID   36700928.
  7. Murugan, Jeff; Weltman, Amanda; Ellis, George F. R., eds. (2009). "Chapter 6. Cosmological quantum billiards by Axel Kleinschmidt and Hermann Nicolai". Proceedings, Foundations of Space and Time: Reflections on Quantum Gravity. Cambridge University Press. pp. 106–124. ISBN   9780521114400. arXiv.org
  8. De Wit, Bernard; Nicolai, H.; Samtleben, H. (2004). "Gauged Supergravities in Three Dimensions: A Panoramic Overview". Proceedings of 27th Johns Hopkins Workshop on Current Problems in Particle Theory: Symmetries and Mysteries of M Theory — PoS(jhw2003). p. 016. doi: 10.22323/1.011.0016 . S2CID   15349626. arXiv.org