المرجع الالكتروني للمعلوماتية
المرجع الألكتروني للمعلوماتية

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Paul Charles William Davies  
  
83   01:48 مساءً   date: 26-3-2018
Author : P Davies
Book or Source : Biography
Page and Part : ...


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Date: 21-3-2018 93
Date: 26-3-2018 188
Date: 25-3-2018 69

Born: 22 April 1946 in London, England


Paul Davies's parents were Hugh Augustus Robert Davies and Pearl Vera Davies. He was educated at Woodhouse Grammar School (now Woodhouse College) in North Finchley, a district towards the north side of Greater London. Margaret Thatcher became the Member of Parliament for Finchley in 1959 (she became Prime Minister of Britain twenty years later), and she presented Paul with a copy of Norton's Star Atlas for an outstanding performance in his O level examinations at the 1962 Speech Day at the school. This, Davies writes, was highly significant since ([5] or [6]):-

... I can trace my own decision to become a scientist to more or less that event.

From Woodhouse Grammar School, Paul went to University College, London, where he was awarded a B.Sc. with 1st Class Honours in 1967. He continued to study at University College undertaking research supervised by Michael Seaton and Sigurd Zienau. He was awarded a Ph.D. for his thesis Contributions to Theoretical Physics: (i) Radiation Damping in the Optical Continuum (ii) A Quantum Theory of Wheeler-Feynman Electrodynamics in 1970. Following the award of his doctorate, he spent two years, 1970-72, as a Research Fellow at the Institute of Theoretical Astronomy at the University of Cambridge working with Fred Hoyle. Describing his early research, Davies writes [3]:-

I began work in the field of atomic astrophysics, and worked on the problem of di-electronic recombination in the solar corona. I then moved into cosmology, and the theory of black holes, especially their quantum and thermodynamic properties.

On 28 July 1972, Davies married Susan Vivien Corti Woodcock; they had three daughters and one son. Later in 1972 he was took up a post as Lecturer in Applied Mathematics at King's College, London. He held this lectureship for eight years. During these years he published many important papers including: (with Stephen A Fulling) Radiation from a moving mirror in two dimensional space-time: conformal anomaly (1976) which gives a two-dimensional model of particle production by gravitational fields; Quantum vacuum stress without regularization in two-dimensional space-time (1977) which Davies summarises as follows:-

It is proved that there is a unique conserved stress tensor possessing a local trace, in the two-dimensional quantum theory of massless scalar and spinor fields propagating in a curved space-time;

(with T S Bunch) Covariant point-splitting regularization for a scalar quantum field in a Robertson-Walker universe with spatial curvature (1977) which investigates the vacuum stress tensor for a massless scalar quantum field in the background space-time of a spatially flat Robertson-Walker universe, and that for a massive field in the special case of the Einstein universe; and (with Stephen A Fulling) Quantum vacuum energy in two dimensional space-times (1977) which, the authors write:-

... presents in detail the renormalization theory of the energy-momentum tensor of a two-dimensional massless scalar field which has been used elsewhere to study the local physics in a model of black hole evaporation.

In 1974 Davies published a major monograph The physics of time asymmetry. This, writes Richard Sigal in a review of the reprint of 1977, is:-

... a clear and well referenced introduction to the time asymmetries found in physical processes. Although probably aimed at the professional physicist, this book is self-contained, concisely reviewing all concepts necessary for the arguments and as such should be accessible to others interested in the fundamental question of the "arrow of time". The author discusses in turn the asymmetries found in thermodynamics, cosmology, electromagnetic theory and quantum mechanics.

Much of Davies's work during his time at King's College appears in his 1982 monograph Quantum fields in curved space written with Nicholas D Birrell who wrote his thesis The Application of Quantum Field Theory to Cosmology and Astrophysics (1979) while being advised by Davies. In 1980 Davies was named Professor of Theoretical Physics at the University of Newcastle upon Tyne. He held this position for ten years during which time, in addition to significant research articles, he published many excellent popular science books showing his outstanding abilities as a communicator. Before moving to Newcastle, he had already published books such as The Runaway Universe (1977), The Forces of Nature (1979), and Other Worlds (1980). Examples of the books he published while holding the chair at Newcastle are: The Edge of Infinity (1981); The Accidental Universe (1982); God and the New Physics (1983);Superforce (1984); Quantum Mechanics (1984), (with Julian R Brown) The Ghost in the Atom (1986); Fireball (1987); The Cosmic Blueprint (1987); and (with Julian R Brown) Superstrings: A Theory of Everything? (1988).

In 1990 Davies went to Australia when appointed as Professor of Mathematical Physics at the University of Adelaide. He held this position until 1993 when he became Professor of Natural Philosophy at the University of Adelaide. In 1998 he became a Visiting Professor at Imperial College, London, and an Adjunct Professor at the University of Queensland. In 2001 he became Adjunct Professor of Natural Philosophy at the Australian Centre for Astrobiology, Macquarie University, New South Wales having helped to found this Centre. In 2003 he married Pauline, a science broadcaster. He became College Professor and Director of Beyond: Center for Fundamental Concepts in Science, Arizona State University, in 2006. His efforts to communicate the latest ideas in science to a general audience have, particularly over the last ten years, made him a household name [1]:-

He gives numerous public lectures each year throughout the world and has written twenty-seven books, both popular and specialist works, which have been translated into many languages. He writes regularly for newspapers, journals and magazines in several countries. Among Davies's better-known media productions were a series of 45 minute BBC Radio 3 science documentaries. Two of these became successful books and one, 'Desperately Seeking Superstrings', won the Glaxo Science Writers Fellowship. In early 2000 he devised and presented a three-part series for BBC Radio 4 on the origin of life, entitled 'The Genesis Factor'. His television projects include two six-part Australian series 'The Big Questions' and 'More Big Questions' and a 2003 BBC documentary about his work in astrobiology entitled 'The Cradle of Life'.

Davies has received many honours in addition to those mentioned in the above quotation. For example he had been elected: a fellow of the UK Institute of Physics, a fellow of the Australian Institute of Physics, a fellow of the World Economic Forum, a member of the Royal Literary Society, an honorary member of the Indian Astronomical Society, and an honorary member of the Singapore Institute of Physics. His biography on the World Economic Forum states that he believes that:-

... science is a cultural as well as an economic activity, and that the gulf between the sciences and the arts is damaging and must be bridged by both sides; focuses on the deep questions of existence, and frequently debates science and religion with senior members of the clergy.

Other honours received by Davies include: the ABC Eureka Prize (1991); the University of New South Wales Press Eureka Prize for the book 'The Mind of God' (1992); the Advance Australia Award for outstanding contributions to science (1993); and the Templeton Prize received from the John Templeton Foundation (1995). This was an extremely prestigious award. Davies writes [4]:-

I was awarded the 1995 Templeton Prize for my work on the deeper significance of science. The award was announced at a press conference at The United Nations in New York. The ceremony took place in Westminster Abbey in May 1995 in front of an audience of 700, where I delivered a 30minute address describing my personal vision of science and theology. It was followed by a private meeting in Buckingham Palace, where Prince Philip presented me with a cheque, a medal and a certificate. The judges for the 1995 prize included President George Bush Sr. and Baroness Margaret Thatcher.

His Templeton Prize address, published in [5] and [6], is fascinating to read. Here is a brief extract which gives an indication of Davies's beliefs:-

Some scientists have tried to argue that if only we knew enough about the laws of physics, if we were to discover a final theory that united all the fundamental forces and particles of nature into a single mathematical scheme, then we would find that this superlaw, or theory of everything, would describe the only logically consistent world. In other words, the nature of the physical world would be entirely a consequence of logical and mathematical necessity. There would be no choice about it. I think this is demonstrably wrong. There is not a shred of evidence that the universe is logically necessary. Indeed, as a theoretical physicist I find it rather easy to imagine alternative universes that are logically consistent, and therefore equal contenders for reality.

Certainly the Templeton Prize was a very major award but Davies continued to receive a host of others including: the Asteroid 1992 OG was renamed (6870) Pauldavies (1999); he received the Kelvin Medal from the UK Institute of Physics (2001); he received the Michael Faraday Prize from the Royal Society (2002); he received the American Institute of Physics Science Writing Award (2003); he received the Trotter Prize from Texas A & M University, USA (2004); and received an honorary D.Sc. from Macquarie University (2006). On 11 June 2007 Davies was made a Member of the Order of Australia:-

For service to science, particularly the disciplines of physics, cosmology and astrobiology, as an educator, author and public commentator.

He lists his hobbies as keeping fit and discussing geographical trivia.


 

Articles:

  1. P Davies, Biography.
    http://cosmos.asu.edu/about/bio.htm
  2. P Davies, Books.
    http://cosmos.asu.edu/publications/books.htm
  3. P Davies, Brief History.
    http://cosmos.asu.edu/research/brief_history.htm
  4. P Davies, Templeton Prize.
    http://cosmos.asu.edu/prize.htm
  5. P Davies, Templeton Prize Address.
    http://cosmos.asu.edu/prize_address.htm
  6. P Davies, Physics and the Mind of God, in A Driessen and A Suarez (eds.), Mathematical Undecidability, Quantum Nonlocality and the Question of the Existence of God (Springer, 1997).
  7. Davies, Paul Charles William (1946 - ), Bright Sparcs (University of Melbourne, 2007).
    http://www.asap.unimelb.edu.au/bsparcs/biogs/P004694b.htm

 




الجبر أحد الفروع الرئيسية في الرياضيات، حيث إن التمكن من الرياضيات يعتمد على الفهم السليم للجبر. ويستخدم المهندسون والعلماء الجبر يومياً، وتعول المشاريع التجارية والصناعية على الجبر لحل الكثير من المعضلات التي تتعرض لها. ونظراً لأهمية الجبر في الحياة العصرية فإنه يدرّس في المدارس والجامعات في جميع أنحاء العالم. ويُعجب الكثير من الدارسين للجبر بقدرته وفائدته الكبيرتين، إذ باستخدام الجبر يمكن للمرء أن يحل كثيرًا من المسائل التي يتعذر حلها باستخدام الحساب فقط.وجاء اسمه من كتاب عالم الرياضيات والفلك والرحالة محمد بن موسى الخورازمي.


يعتبر علم المثلثات Trigonometry علماً عربياً ، فرياضيو العرب فضلوا علم المثلثات عن علم الفلك كأنهما علمين متداخلين ، ونظموه تنظيماً فيه لكثير من الدقة ، وقد كان اليونان يستعملون وتر CORDE ضعف القوسي قياس الزوايا ، فاستعاض رياضيو العرب عن الوتر بالجيب SINUS فأنت هذه الاستعاضة إلى تسهيل كثير من الاعمال الرياضية.

تعتبر المعادلات التفاضلية خير وسيلة لوصف معظم المـسائل الهندسـية والرياضـية والعلمية على حد سواء، إذ يتضح ذلك جليا في وصف عمليات انتقال الحرارة، جريان الموائـع، الحركة الموجية، الدوائر الإلكترونية فضلاً عن استخدامها في مسائل الهياكل الإنشائية والوصف الرياضي للتفاعلات الكيميائية.
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