Roger Penrose

Roger Penrose, OM, FRS (UK: /ˈɹɒd͡ʒə ˈpenˌɹoz/; Colchester, 8 August 1931), is a British mathematical physicist and Emeritus Professor of Mathematics at Oxford University. He is recognized for his work in mathematical physics, in particular for his contributions to the theory of general relativity and to cosmology. He has also directed his efforts in the field of recreational mathematics and is a controversial philosopher.

He was elected a Fellow of the Royal Society of London in 1972. He was made a Knight Bachelor in 1994.

Penrose has made contributions to the mathematical physics of general relativity and cosmology. He has received several prizes and honors, including the 1988 Wolf Prize in physics, which he shared with Stephen Hawking for the Penrose-Hawking singularity theorems, the 1990 Aventis Prize, and the 2020 Nobel Prize in Physics "for the discovery that the formation of black holes is a strong prediction of the general theory of relativity ", which he shared with Reinhard Genzel and Andrea Ghez.

Biography

Penrose is the son of scientist Lionel Penrose and Margaret Leathes, and brother of theoretical physicist Oliver Penrose and chess player Jonathan Penrose. He was born in Colchester, Essex, England.

Career

In 1955, while still a student, Penrose reinvented the generalized inverse (also known as the Moore-Penrose inverse)

Penrose earned his Ph.D. from Cambridge in 1958, writing a thesis on tensor methods in algebraic geometry under the supervision of the well-known algebraist and geometer John A. Todd. In 1965 Penrose proved the first singularity theorem, which states that a gravitational singularity inevitably forms during the collapse of a sufficiently massive star (a process in which a black hole is formed), and the physicist later built on this work. Stephen Hawking to prove the Second Singularity Theorem, which establishes the past geodesic incompleteness of all expanding globally hyperbolic space-time satisfying the strong energy condition.

Urs Schmid Oil Painting (1995) of a Penrose Thesssation.

In 1967, Penrose invented the theory of twistors that maps geometric objects from a Minkowski space into a complex space in four dimensions with the metric signature (2,2). Despite the failure of the initial hope that twistors could lead to a quantum theory of gravity, twistors have found numerous applications in field theory, in the computation of scattering amplitudes, in superstring theory, and in physics. theory of partial differential equations.

In 1969 he conjectured the hypothesis of cosmic censorship. It proposes (informally) that the universe protects us from the inherent unpredictability of singularities (such as black holes) by hiding them from view. This form is now known as the weak censorship hypothesis; in 1979, Penrose formulated a stronger version called the strong hypothesis of censorship. In conjunction with the BKL conjecture and problems with nonlinear stability, solving the cosmic censorship conjecture is one of the most important problems in the theory of relativity.

Roger Penrose is best known for his discovery in 1974 of Penrose tilings, which are made up of two tesserae that can only tessellate the plane aperiodically. Similar patterns were found in the organization of atoms in quasicrystals in 1984. His most important contribution may be his 1971 introduction of spin lattices, which later became an essential component of loop quantum gravity. Penrose was influential in popularizing conformal diagrams commonly known as Penrose diagrams, which have become common currency in theoretical physics.

In 2004 Penrose published Reality Road: A Complete Guide to the Laws of the Universe, a 1,471-page book intended to provide a general guide to the laws of physics, and one of the best books dissemination of the last decades.

Penrose's theory of mind

Penrose has argued that there must be something of a non-computable nature in the physical laws that describe mental activity. This argument is based on Gödel's incompleteness theorem, which speaks of the impossibility of a formal proof of a certain mathematical proposition, even though for human understanding it is in fact true. Also in the ideas of Stuart Hameroff. Both Penrose and Hameroff postulate that the mind and the brain are two separable entities. Hameroff, an anesthetist, does so through his studies on microtubules and the cellular cytoskeleton, especially in neurons, while Penrose does so from the incompleteness theorem.

The model defended by Penrose, along with Hameroff, tries to explain events that are difficult to understand through conventional neuroscience, and to do so, relies on revised aspects of quantum theory (for example, the concept of coherence), as well as the existence of a physical phenomenon, hitherto unpublished, that seems to occur inside neurons when the quantum wave function collapses by itself in an orchestrated objective reduction.

His considerations in favor of the aforementioned cell organelles are supported by several suggestions:

1. These entities exist in all types of cells, so there would be an explanation for the complex behaviors of simple beings without neuronal nervous system, such as paramecio.
2. Because each neuron contains a huge amount of microtubules, the computing power of the brain would increase by a factor of 10¹³.
3. Within the microtubule there could be a specially ordered state of water, called "vicinal" water, which could help to maintain the desired quantum coherence.
4. The action of general anesthetics could interfere with microtubular activity, hypothesis supported by the fact that these anesthetics also act on simple beings. Example: amoebas or paramecios.

Penrose suggests that no computing machine can be as intelligent as a human being, since formal algorithmic systems (that is, the sequenced instruction systems on which computers are built) will never give them the ability to understand and find truths that human beings possess.

Penrose's theory of aeons

Roger Penrose explained his theory at the University of Santiago de Compostela, where he collected the Fonseca award.

This theory is known as conformal cyclical cosmology.

Since 2005 Penrose has been working on a new cyclical cosmological scheme consistent with the accelerated expansion of the Universe, in which it would be due to the (large-scale) repulsive effects of the gravitational field described by Einstein's field equations with a positive cosmological constant.

Penrose's interpretation of quantum mechanics

Another field of interest for Penrose has been the measurement problem of quantum mechanics, which he links to a theory of quantum gravity. For Penrose, a future theory of quantum gravity, when describing space-time quantum, would contain a new ingredient that could solve the measurement problem. For Penrose, the uncertainty caused by quantum effects in the curvature of space-time would be a factor that can lead to an objective collapse of the wave function, and he has offered a speculative interpretation of how this would be possible, known as the Penrose interpretation of mechanics. quantum.

Nobel Prize

In 2020, Penrose was awarded half of the Nobel Prize in Physics for the discovery that the formation of black holes is a robust prediction of the general theory of relativity, the other half was shared between Reinhard Genzel and Andrea M.ghez.

Books

• PenroseRoger, The new mind of the emperorMondadori, 1989, ISBN 84-397-1786-5.
• PenroseRoger, The shadows of the mind: towards a scientific understanding of consciousness, Editorial Crítica, 1996, ISBN 84-7423-771-8.
• PenroseRoger, Prologue Einstein 1905: a miraculous year, Planet, 2004, ISBN 84-8432-215-7.
• PenroseRoger, The Way to Reality: A Complete Guide to the Laws of the Universe, Editorial Debate, 2006, ISBN 84-8306-681-5.
• PenroseRoger, Cycles of time, Editorial Debate, 2010, ISBN 978-84-8306-922-6. Debolsillo, 2011, ISBN 978-84-9989-199-6.
• PenroseRoger, Fashion, faith and fantasy in the new physics of the universe, Editorial Debate, 2017, ISBN 978-84-9992-789-3.

As a co-author

• PenroseRoger. HawkingStephen, Quantum and cosmological issues, Editorial Alliance, 1995, ISBN 84-206-2756-9.
• HawkingStephen. PenroseRoger, The Nature of Space and Time, Editorial Debate, 1996, ISBN 84-8306-032-9.
• PenroseRoger & Abner Shimony, Nancy Cartwright, Stephen Hawking, Malcolm Longair, Big, small and human mindCambridge University Press, 1999. ISBN 84-8323-047-X.

Academic texts

• PenroseRoger, Techniques of Differential Topology in Relativity, Society for Industrial & Applied Mathematics, 1972, ISBN 0-89871-005-7.
• PenroseRoger, and Wolfgang Rindler, Spinors and Space-Time: Volume 1, Two-Spinor Calculus and Relativistic Fields, Cambridge University Press, 1987, ISBN 0-521-33707-0.
• PenroseRoger, and Wolfgang Rindler, Spinors and Space-Time: Volume 2, Spinor and Twistor Methods in Space-Time GeometryCambridge University Press, 1988, ISBN 0-521-34786-6.