Roger Penrose

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Roger Penrose (2005)

Sir Roger Penrose OM (born August 8, 1931 in Colchester , Essex ) is a British mathematician and theoretical physicist whose work in the fields of mathematical physics and cosmology are highly respected. He has also appeared in numerous popular science books on philosophy . He was awarded half of the Nobel Prize in Physics in 2020 for discovering that black hole formation is a robust predictor of theGeneral relativity is (laudation).

Life

Roger Penrose is the son of the medical geneticist Lionel Penrose (founder of the Colchester Survey to uncover the genetic and environmental causes of mental illness) and Margaret Leathes, a doctor. He is the brother of the physicist Oliver Penrose and the ten-time (1958-1969) British chess master and psychologist Jonathan Penrose . His father emigrated to London , Ontario , Canada , in 1939 (where he was director of the hospital's psychiatric clinic), where Penrose attended school. In 1945 the family returned to England and Penrose attended University College London , where his father was a professor of genetics.

After his bachelor's degree, he moved to Cambridge University to work in algebraic geometry with William Vallance Douglas Hodge , but then moved to John Arthur Todd , where he received his doctorate in 1957. He also attended physics courses with Paul Dirac and Hermann Bondi and was also heavily influenced by the cosmologist Dennis Sciama . In 1956/57 he was an Assistant Lecturer at Bedford College in London, then moved to St. John's College in Cambridge as a Research Fellow . 1959–1961 he worked in the USA at Princeton University and Syracuse University , then 1961–1963 at King's College in Cambridge and 1963/64 as visiting professor at the University of Texas at Austin . In 1964 he became a reader at Birkbeck College in London and, in 1966, professor of applied mathematics there.

Penrose was Rouse Ball Professor at Oxford University from 1973 to 1998 . He then became a geometry professor at Gresham College , London .

From 1992 to 1995 he was President of the International Society on General Relativity and Gravitation .

He was married to the American Joan Isabel Wedge from 1959 to 1981, with whom he has three children. In 1988 he married the teacher Vanessa Thomas, with whom he had two children.

Publicity

Penrose is known to the public for his popular scientific work: in several books ( The Emperor's New Mind , Shadows of the Mind , The Large, the Small and the Human Mind ) he deals with problems of consciousness and artificial intelligence in mathematical and physical terms .

Services

physics

Temperature fluctuations in cosmic background radiation, measured by WMAP.

Penrose introduced spin networks , from which the theory of loop quantum gravity and the twistor theory were later developed. In particular, the expansion of the twistor theory, which he founded and which he sees as the basis of a comprehensive physical theory of fundamental interactions and particles, was one of the main concerns of his career as a scientist. Another fundamental finding in cosmology goes back to him and Stephen Hawking : the Hawking-Penrose theorem, according to which solutions with singularities (e.g. big bang or black holes) necessarily exist in Einstein's field equations (see singularity theorem ). According to Penrose, singularities are always shielded by event horizons and bare singularities do not occur ( Penrose's Cosmic Censorship Hypothesis). Finally, with the Weyl curvature hypothesis , Penrose made a proposal in 1979 as to how the second law of thermodynamics could be rooted in cosmology, and how on the one hand the cosmological arrow of time and on the other the impressive observed spatial homogeneity and isotropy of the universe could be explained. In connection with the general theory of relativity, he also developed the Penrose diagram , which can be used to graphically represent the global structure of spacetime .

Penrose calls for the development of a theory of quantum gravity , taking into account a certain unpredictability in the world of quantum phenomena or their interpretations and the integration of the principles of Einstein's general theory of relativity. He calls this new physics OR physics .

In 2010 Penrose, together with Wahe Gursadjan, interpreted anomalies (after them concentric circles) in the WMAP data of the cosmic background radiation as evidence of activities before the Big Bang (collisions of supermassive black holes). He sees this as confirmation of a model of cyclic universes (CCC, Conformal Cyclic Cosmology) proposed by him, which provides for successive universes and is thus in contrast to the model of parallel universes . Accordingly, the end of an expanded universe is followed by a new big bang, which presupposes a symmetry or conformal (i.e. essentially scale-independent) transformation between the beginning and the end (this is related to his Weyl curvature hypothesis to explain the entropy of the universe). But since massive particles are present in the known universe and thus scales are defined, he also postulates that the particles lose their mass in the end phase. He also postulates massless particles to explain temperature fluctuations in the cosmic background radiation, which convey gravity and make up dark matter , and calls them Erebon after Erebos .

mathematics

Implementation of the 5-fold symmetrical tile structure by Roger Penrose
Penta Plexity

As a student, Penrose discovered the Penrose inverses of matrices in 1955 .

In 1974 Penrose discovered several related small non-periodic sets of tiles, especially several aperiodic pairs . Such tiles the plane can be parquetted, but none of these tilings is periodic (that is, does not repeat in exactly the same way). But they always have a certain order and are fivefold rotationally symmetrical. They are therefore called quasi-periodic . This Penrose tiling is derived from a hierarchically structured pack of regular pentagons (see below). In 1984 similar structures were found in quasicrystals .

Among other things, Roger Penrose invented the Penrose triangle , a triangle with three right angles standing on top of each other. The construction, which is not possible in reality, animated the Dutch graphic artist MC Escher to create the pictures Waterfall and Belvedere .

In math, beauty is often associated with simplicity. Penrose comes to the conclusion that in mathematics, simplicity is not beautiful as such, but above all unexpected simplicity .

Physics and consciousness, work on the fundamentals of quantum mechanics

Penrose tries in several works with a three-world theory to describe metaphysical problems in popular science and to explain his proposed solutions. From the first world of the platonic-mathematical logos, the physical reality is only a small excerpt (other natural laws would be conceivable). The third, spiritual world is the consciousness of the individual.

Like Stuart Hameroff in search of “a physical home for consciousness”, Penrose proposes a - controversially discussed - model according to which this is essentially based on quantum mechanical effects such as EPR phenomena , quantum entanglement or quantum non-locality and Quantum coherence is based, which it localizes in the microtubules of the cell skeleton and the interface with the neuron .

According to this theory, subtle physical processes on the nanometer scale (10 −9 m) in the border area between classical physics and quantum mechanics in a highly developed nervous system lead to what we call “ mind ” or “ consciousness ”. However , the Hameroff-Penrose model is rejected by other quantum physicists, neurobiologists and philosophers such as Metzinger , Roth or Koch . However, he also received support for his theory from various natural scientists, such as the physicists Hans-Peter Dürr and Amit Goswami and the chemist Rolf Froböse .

In 2003, Penrose and the Dutch experimental physicist Dirk Bouwmeester proposed to test his hypothesis of the influence of the gravitational curvature of space on the superposition of quantum mechanical states on nano mirrors.

Awards

Publications (selection)

  • Collected Works , 6 volumes, Oxford University Press 2011.
  • Tensor Methods in Algebraic Geometry . University of Cambridge 1956. ( Dissertation )
  • Geometrical Algebras: A New Approach to Invariant Theory . Bedford College , London 1957.
  • Techniques of Differential Topology in Relativity , SIAM, Philadelphia 1972.
  • with Wolfgang Rindler : Spinors and Space-Time. Volume 1: Two-Spinor Calculus and Relativistic Fields. Cambridge Monographs on Mathematical Physics. Cambridge University Press, ISBN 0-521-33707-0 .
  • with Wolfgang Rindler: Spinors and Space-Time. Volume 2: Spinor and Twistor Methods in Space-Time Geometry. Cambridge Monographs on Mathematical Physics. Cambridge University Press, ISBN 0-521-34786-6 .
  • The Emperor's New Mind. Concerning Computers, Minds, and the Laws of Physics. Oxford University Press, 1989, ISBN 0-14-014534-6 .
    • German edition: Computer Thinking. The emperor's new clothes or the debate about artificial intelligence, consciousness and the laws of nature. Spectrum of Science, Heidelberg 1991, ISBN 3-8274-1332-X .
  • Shadows of the Mind. A Search for the Missing Science of Consciousness. Oxford University Press, 1994, ISBN 0-19-853978-9 .
    • German edition: Shadow of the Spirit. Paths to a New Physics of Consciousness. Spectrum, Heidelberg / Berlin / Oxford 1995, ISBN 3-86025-260-7 .
  • with Stephen Hawking : The Nature of Space and Time. Princeton University Press, 1996, ISBN 0-691-03791-4 .
  • The Large, the Small and the Human Mind. Cambridge University Press, 1997, ISBN 0-521-56330-5 .
    • German edition: The big, the small and the human spirit. Spectrum, Heidelberg / Berlin 2002
  • Quantum Computation, Entanglement and State Reduction. In: Philosophical Transactions of the Royal Society of London. Series A, 356, 1998, pp. 1927-1939.
  • The Road to Reality. A Complete Guide to the Laws of the Universe. Jonathan Cape, London 2004, ISBN 0-224-04447-8 .
    • German partial translation: The way to reality: the partial translation for beginners , translator Anita Ehlers, contributions by Markus Pössel , Spektrum Akademischer Verlag 2010
  • Cycles of Time. Bodley Head, 2010, ISBN 978-0-224-08036-1 .
    • German: Cycles of time. A new unusual view of the universe. Translated by Thomas Filk. Spektrum Akademischer Verlag, Heidelberg 2011, ISBN 978-3-8274-2801-1 .
  • Fashion, Faith, and Fantasy in the New Physics of the Universe , Princeton University Press, Princeton, New Jersey, USA 2016, ISBN 978-0-691-11979-3 .

Individual evidence

  1. ↑ Laudation: for the discovery that black hole formation is a robust prediction of the general theory of relativity , Press Release, Nobel Prize Physics 2020
  2. ^ Roger Penrose (born August 8, 1931), British Professor. In: prabook.com. Retrieved January 4, 2019 .
  3. ↑ Roger Penrose: Computer Thinking: The Debate About Artificial Intelligence, Consciousness, and the Laws of Physics . Spectrum Academic Publishing House, 2001, ISBN 3-8274-1332-X .
  4. ↑ Roger Penrose: Shadow of the Spirit . Spektrum Verlag, 1995, ISBN 3-86025-260-7 .
  5. ^ Roger Penrose, Abner Shimony, Nancy Cartwright , Stephen W. Hawking : The Great, the Small, and the Human Mind . Spektrum Akademischer Verlag, 2002, ISBN 3-8274-1331-1 .
  6. ↑ Wahagn Grigori Gursadjan, Roger Penrose: On CCC-predicted concentric low-variance circles in the CMB sky . In: Eur. Phys. J. Plus . tape 128 , 2013, p. 22 , arxiv : 1302.5162 [abs] (English).
  7. ↑ Christian Müller: The cyclical universe. In: wienerzeitung.at. May 22, 2015, accessed January 4, 2019 .
  8. ^ Roger Penrose: The basic ideas of conformal cyclic cosmology . In: AIP Conference Proceedings . tape 1446 , 2012, p. 233 , doi : 10.1063 / 1.4727997 (English).
  9. ^ Roger Penrose: The Role of Aesthetics in Pure and Applied Mathematical Research . In: Bull. Inst. Math. Appl. Volume 10, 1974, pp. 266-271.
  10. ↑ [1] , last seen on May 3, 2020.
  11. ↑ The soul also exists after death , last seen on May 3, 2020.
  12. ^ Roger Penrose: On Gravity's Role in Quantum State Reduction . In: General Relativity and Gravitation . 28, No. 5, 1996, pp. 581-600. bibcode : 1996GReGr..28..581P . doi : 10.1007 / BF02105068 .
  13. ^ University of Leiden 2011 on Penrose
  14. ^ W. Marshall, C. Simon, Penrose, Bouwmeester: Towards the quantum superposition of a tiny mirror. In: Phys. Rev. Lett. Volume 91, 2003, pp. 130401-1, pdf
  15. ^ Members: Roger Penrose. Royal Irish Academy, accessed May 11, 2019 .
  16. ↑ Dissemination Award. In: claymath.org. March 8, 2018, accessed January 4, 2019 .

Web links

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personal data
SURNAME Penrose, Roger
BRIEF DESCRIPTION English mathematician and theoretical physicist
DATE OF BIRTH August 8, 1931
PLACE OF BIRTH Colchester , Essex , England