Abhay Vasant Ashtekar

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Abhay Vasant Ashtekar (born July 5, 1949 in Shirpur , India ) is an Indian-American theoretical physicist who deals with gravitational physics. He was the professor of physics and the director of the Institute of Gravitational Physics and Geometry at Pennsylvania State University . As the creator of the Ashtekar variable, he is one of the founders of loop quantum gravity .

biography

Ashtekar grew up in several cities in India. He graduated from the University of Bombay with a bachelor's degree in 1969 and received his doctorate in 1974 from the University of Chicago with Robert Geroch . 1983 to 1985 he was a professor at the University of Paris VI and from 1984 professor at Syracuse University ( Erastus Franklin Holden Professor ), where he had been researching since 1980. From 1993 he was Eberly Professor of Physics at Pennsylvania State University ( Eberly Professor of Physics) and Director of the "Institute for Gravitation and the Cosmos".

He was visiting professor and visiting scholar at various Indian universities such as the Raman Institute in Bangalore , Utrecht , the University of Maryland , the Perimeter Institute , the Max Planck Institute for Physics and Astrophysics in Garching and Beijing .

Ashketar is a co-founder of the theory of loop quantum gravity , which he also applied to cosmological questions (Loop Quantum Cosmology). One of his most important contributions was the introduction of new Ashtekar variables that a connection provide representation of the canonical general relativity and led to the loop variable of loop quantum gravity. With his group he also developed a quantum Riemannian geometry as the basis for loop quantum gravity with a microscopic “atomized” description of space-time. Ashtekar developed the cosmological model of the Quantum Bounce , which replaces the Big Bang and associated singularities (infinities). From this he also developed predictions that were confirmed by observing the cosmic background radiation and also made predictions for future measurements. He also made contributions to the asymptotic, global description of space-time and gravitational waves in general relativity in full nonlinear treatment. Together with Badri Krishnan, he developed the concept of quasi-local, dynamic or isolated event horizons, which was used in the numerical simulation of the collision of black holes and in investigations into the quantum mechanical description of the annihilation of black holes. Ashtekar also showed that a cosmological constant had previously undetected effects on the theory of gravitational waves.

In 1979 he received first prize from the Gravity Research Foundation. 1981 to 1985 he was a Sloan Research Fellow . In 1996 he became an Honorary Fellow of the Indian Academy of Sciences and in 1997 a foreign member of the National Academy of Sciences of India and a Fellow of the American Physical Society . He is an honorary doctor from the Friedrich Schiller University Jena (2005) and the University of Aix-Marseille II (2010). In 2004 he received the Senior Scientist Prize from the Alexander von Humboldt Foundation. From 2007 to 2010 he was President of the International Society for General Relativity and Gravitation. In 2016 he was elected to the National Academy of Sciences . For 2019 he was awarded the Einstein Prize of the American Physical Society. He is a Fellow of the American Association for the Advancement of Science .

Fonts (selection)

  • Asymptotic Quantization , Bibliopolis, Naples 1987
  • New perspectives in canonical gravity , Bibliopolis, Naples 1988
  • Editor with John Stachel : Conceptual problems of quantum gravity , Birkhäuser 1991 (Proceedings 1988 Osgood Hill Conference)
  • Lectures on nonperturbative canonical gravity , World Scientific 1991
  • as editor: 100 years of relativity - Space-time structure: Einstein and beyond, World Scientific 2005
  • Editor with B. Berger. J. Isenberg, MAH MacCallum: General Relativity and Gravitation: A Centenary Perspective, (Commissioned by the International Society on General Relativity and Gravitation to celebrate the 100th anniversary of Einstein's discovery of general relativity), Cambridge University Press, Cambridge, 2015
    • therein by Ashtekar, Martin Reuter , Carlo Rovelli: From General Relativity to quantum gravity , Arxiv and introductions by the editors, Arxiv
  • with Jorge Pullin (Ed.): Loop Quantum Gravity: First 30 Years , World Scientific 2017
    • In it the overview of Ashtekar, Pullin, Arxiv

Some essays, unless cited in the main part:

  • with Carlo Rovelli , Lee Smolin : Weaving a classical geometry with quantum threads , Phys. Rev. Lett., Vol. 69, 1992, pp. 237-240, Arxiv
  • Mathematical Problems of Non-perturbative Quantum General Relativity , Les Houches Lectures 1992, Arxiv
  • Quantum Geometry and Gravity: Recent Advances, plenary lecture 16th International Conference on General Relativity and Gravitation, Durban 2001, Arxiv
  • with Jerzy Lewandowski : Background independent quantum gravity: a status report , Classical and Quantum Gravity, Volume 21, 2004, R 53, Arxiv
  • Gravity and the Quantum , New J. Physics, Volume 7, 2005, p. 198, Arxiv
  • Physics from geometry, Nature Physics, Volume 2, 2006, pp. 726-727
  • Loop quantum cosmology - an overview , Gen. Rel.Grav., Volume 41, 2009, pp. 707-741 Arxiv
  • with Parampreet Singh: Loop quantum cosmology: a status report , Class. Quant. Grav., Volume 28, 2011, p. 213001, Arxiv
  • Ashtekar variables , Scholarpedia 2015

Web links

Individual evidence

  1. ↑ Life data according to Thomson Gale: American Men and Women of Science. 2004.
  2. ↑ Abhay Vasant Ashtekar in the Mathematics Genealogy Project (English)Template: MathGenealogyProject / Maintenance / id used
  3. ↑ Ashtekar, New variables for Classical and quantum gravity, Phys. Rev. Lett., Vol. 57, 1987, pp. 2244-2247
  4. ↑ Ashtekar, A new Hamiltonian formulation of general relativity, Phys. Rev. D, Volume 36, 1987, pp. 1587-1603
  5. ↑ Ashtekar, Christopher Isham : Representations of the holonomy algebras of gravity and non-Abelian gauge theories, Class. Quant. Gravity, Vol. 9, 1992, pp. 1433-1468, Arxiv
  6. ↑ Ashtekar, Recent Developments in Classical and Quantum Theories of Connections, Including General Relativity, Arxiv , 1992
  7. ↑ Ashtekar, Lewandowski, Representation Theory of Analytic Holonomy C * Algebras, in: J. Baez (Ed.), Knots and quantum geometry, Oxford UP 1994, Arxiv
  8. ↑ Ashtekar, Lewandowski: Quantum theory of geometry, part 1, class. Quant. Grav., Volume 14, 1997, A 55 - A 82, Arxiv , Part 2, Adv. Theor. Math. Phys., Vol. 1, 1998, pp. 388-429, Arxiv , Part 3, Ashtekar, Corichi, Zapata, Class.Quant.Grav. , Vol. 15, 1998, pp. 2955-2972 Arxiv
  9. ↑ Ashtekar, Tomasz Pawlowski, Parampreet Singh, Quantum nature of the big bang, Phys. Rev. Lett., Vol. 96, 2006, p. 141301, Arxiv
  10. ↑ Ashtekar, Big Bang and the Quantum, AIP Conf. Proc. 2010, Arxiv
  11. ↑ Ashtekar, Aurelien Barrau, Loop quantum cosmology: From pre-inflationary dynamics to observations, Arxiv 2015
  12. ↑ Ashtekar, Badri Krishnan: Isolated and dynamical horizons and their applications , Living Reviews in Relativity, Volume 7, 2004, 10, Arxiv
  13. ↑ Ashtekar, Beatrice Bonga, Aruna, Kesavan, Gravitational waves from isolated systems: Surprising consequences of a positive cosmological constant, Phys. Rev. Lett., Volume 116, 2016, p. 051101, Arxiv
  14. ↑ Ashtekar, Implications of a positive cosmological constant for general relativity, Rep. Progr. Phys., Arxiv 2017
personal data
SURNAME Ashtekar, Abhay Vasant
BRIEF DESCRIPTION Indian-American theoretical physicist
DATE OF BIRTH July 5, 1949
PLACE OF BIRTH Shirpur , India