Contributions to Theoretical Physics: (i) Radiation Damping in the Optical Continuum; (ii) A Quantum Theory of Wheeler–Feynman Electrodynamics[citation needed] (1970)
Davies' research interests are theoretical physics, cosmology and astrobiology; his research has been mainly in the area of quantum field theory in curved spacetime. His notable contributions are the so-called Fulling–Davies–Unruh effect,[4] according to which an observer accelerating through empty space will be subject to a bath of induced thermal radiation, and the Bunch–Davies vacuum state, often used as the basis for explaining the fluctuations in the Cosmic microwave background left over from the Big Bang. A paper co-authored with Stephen Fulling and William Unruh was the first to suggest that black holes evaporating via the Hawking effect lose mass as a result of a flux of negative energy streaming into the hole from the surrounding space. Davies has had a longstanding association with the problem of time's arrow, and has also identified the mystery of 'dark energy' as one of the most important issues facing fundamental science.[5] Davies was also an early proponent of the theory that life on Earth may have come from Mars cocooned in rocks ejected by asteroid and comet impacts. He is also a propagator of scientific research and technology development in order to prevent future comet impacts threatening the development or existence of humankind.[6] He proposed that a one-way trip to Mars could be a viable option in the future. During his time in Australia he helped establish the Australian Centre for Astrobiology.
Davies was a co-author with Felisa Wolfe-Simon on the 2011 Science article "A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus".[7] Reports refuting the most significant aspects of the original results were published in the same journal in 2012.[8] Following the publication of the articles challenging the conclusions of the original Science article first describing GFAJ-1, the website Retraction Watch argued that the original article should be retracted because of misrepresentation of critical data.[9][10]
Davies writes and comments on scientific and philosophical issues. He made a documentary series for BBC Radio 3, and two Australian television series, The Big Questions and More Big Questions. His BBC documentary The Cradle of Life featured the subject of his Faraday Prize lecture. He writes regularly for newspapers and magazines worldwide. He has been guest on numerous radio and television programmes including the children's podcast programme Ask A Biologist.
Davies wrote an article in The Wall Street Journal describing the background to the December 2010 arsenic bacteria press conference and stating that he supported the finding of Felisa Wolfe-Simon that arsenic can replace phosphorus because "I had the advantage of being unencumbered by knowledge. I dropped chemistry at the age of 16, and all I knew about arsenic came from Agatha Christie novels."[16] He also made the statement, "Well, I would be astonished if this was the only arsenic-based organism on Earth and Felisa just happened to scrape it up from the bottom of Mono Lake on the first try, It's quite clear that it is the tip of an iceberg. I think it's a window into a whole new world of microbiology. And as a matter of fact, she already has 20 or so candidate other organisms that we're very anxious to take a look at. I think we're going to see a whole new domain of life here."[17] It was later independently demonstrated that the organism's DNA contained no arsenic at all.[18][19][20][21] Concerns have been raised about his responsibility as one of Wolfe-Simon's co-authors.[22]
In popular culture
The 1996 novel Naive, Super, by Norwegian writer Erlend Loe (translated by Tor Ketil Solberg), refers to Davies frequently.
Numbers (season 5, episode 12) refers to Paul Davies' Cosmic Think Tank at Arizona State.
Arsenic is a chemical element; it has symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a notoriously toxic metalloid. It has various allotropes, but only the grey form, which has a metallic appearance, is important to industry.
The Big Bang is a physical theory that describes how the universe expanded from an initial state of high density and temperature. The Big Bang theory was inspired by the discovery of the expanding Universe by Edwin Hubble. It was first proposed in 1927 by Roman Catholic priest and physicist Georges Lemaître. Lemaître reasoned that if we go back in time, there must be fewer and fewer matter, until all the energy of the universe is packed in a unique quantum. Various cosmological models of the Big Bang explain the evolution of the observable universe from the earliest known periods through its subsequent large-scale form. These models offer a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the cosmic microwave background (CMB) radiation, and large-scale structure. The overall uniformity of the universe, known as the flatness problem, is explained through cosmic inflation: a sudden and very rapid expansion of space during the earliest moments. However, physics currently lacks a widely accepted theory of quantum gravity that can successfully model the earliest conditions of the Big Bang.
Hypothetical types of biochemistry are forms of biochemistry agreed to be scientifically viable but not proven to exist at this time. The kinds of living organisms currently known on Earth all use carbon compounds for basic structural and metabolic functions, water as a solvent, and DNA or RNA to define and control their form. If life exists on other planets or moons it may be chemically similar, though it is also possible that there are organisms with quite different chemistries – for instance, involving other classes of carbon compounds, compounds of another element, or another solvent in place of water.
A quark is a type of elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. All commonly observable matter is composed of up quarks, down quarks and electrons. Owing to a phenomenon known as color confinement, quarks are never found in isolation; they can be found only within hadrons, which include baryons and mesons, or in quark–gluon plasmas. For this reason, much of what is known about quarks has been drawn from observations of hadrons.
Sir Roger Penrose is an English mathematician, mathematical physicist, philosopher of science and Nobel Laureate in Physics. He is Emeritus Rouse Ball Professor of Mathematics in the University of Oxford, an emeritus fellow of Wadham College, Oxford, and an honorary fellow of St John's College, Cambridge, and University College London.
John Charlton Polkinghorne was an English theoretical physicist, theologian, and Anglican priest. A prominent and leading voice explaining the relationship between science and religion, he was professor of mathematical physics at the University of Cambridge from 1968 to 1979, when he resigned his chair to study for the priesthood, becoming an ordained Anglican priest in 1982. He served as the president of Queens' College, Cambridge, from 1988 until 1996.
Charles Hard Townes was an American physicist. Townes worked on the theory and application of the maser, for which he obtained the fundamental patent, and other work in quantum electronics associated with both maser and laser devices. He shared the 1964 Nobel Prize in Physics with Nikolay Basov and Alexander Prokhorov. Townes was an adviser to the United States Government, meeting every US president from Harry S. Truman (1945) to Bill Clinton (1999).
Martin John Rees, Baron Rees of Ludlow, is a British cosmologist and astrophysicist. He is the fifteenth Astronomer Royal, appointed in 1995, and was Master of Trinity College, Cambridge, from 2004 to 2012 and President of the Royal Society between 2005 and 2010.
John David Barrow was an English cosmologist, theoretical physicist, and mathematician. He served as Gresham Professor of Geometry at Gresham College from 2008 to 2011. Barrow was also a writer of popular science and an amateur playwright.
George Francis Rayner Ellis, FRS, Hon. FRSSAf, is the emeritus distinguished professor of complex systems in the Department of Mathematics and Applied Mathematics at the University of Cape Town in South Africa. He co-authored The Large Scale Structure of Space-Time with University of Cambridge physicist Stephen Hawking, published in 1973, and is considered one of the world's leading theorists in cosmology. From 1989 to 1992 he served as president of the International Society on General Relativity and Gravitation. He is a past president of the International Society for Science and Religion. He is an A-rated researcher with the NRF.
Simon Conway Morris is an English palaeontologist, evolutionary biologist, and astrobiologist known for his study of the fossils of the Burgess Shale and the Cambrian explosion. The results of these discoveries were celebrated in Stephen Jay Gould's 1989 book Wonderful Life. Conway Morris's own book on the subject, The Crucible of Creation (1998), however, is critical of Gould's presentation and interpretation.
Bernard d'Espagnat was a French theoretical physicist, philosopher of science, and author, best known for his work on the nature of reality. Wigner-d'Espagnat inequality is partially named after him.
Michał Kazimierz Heller is a Polish philosopher, theoretical physicist, cosmologist, theologian, and Roman Catholic priest. He is a professor of philosophy at the Pontifical University of John Paul II in Kraków, Poland, and an adjunct member of the Vatican Observatory staff.
Walter Eduard Thirring was an Austrian physicist after whom the Thirring model in quantum field theory is named. He was the son of the physicist Hans Thirring.
Felisa Wolfe-Simon is an American microbial geobiologist and biogeochemist. In 2010, Wolfe-Simon led a team that discovered GFAJ-1, an extremophile bacterium that they claimed was capable of substituting arsenic for a small percentage of its phosphorus to sustain its growth, thus advancing the remarkable possibility of non-RNA/DNA-based genetics. However, these conclusions were immediately debated and criticized in correspondence to the original journal of publication, and have since come to be widely disbelieved, though they have never been disputed by any legitimate scientific studies. In 2012, two reports refuting the most significant aspects of the original results were published in the same journal in which the original findings had been previously published.
Arsenic biochemistry refers to biochemical processes that can use arsenic or its compounds, such as arsenate. Arsenic is a moderately abundant element in Earth's crust, and although many arsenic compounds are often considered highly toxic to most life, a wide variety of organoarsenic compounds are produced biologically and various organic and inorganic arsenic compounds are metabolized by numerous organisms. This pattern is general for other related elements, including selenium, which can exhibit both beneficial and deleterious effects. Arsenic biochemistry has become topical since many toxic arsenic compounds are found in some aquifers, potentially affecting many millions of people via biochemical processes.
GFAJ-1 is a strain of rod-shaped bacteria in the family Halomonadaceae. It is an extremophile that was isolated from the hypersaline and alkaline Mono Lake in eastern California by geobiologist Felisa Wolfe-Simon, a NASA research fellow in residence at the US Geological Survey. In a 2010 Science journal publication, the authors claimed that the microbe, when starved of phosphorus, is capable of substituting arsenic for a small percentage of its phosphorus to sustain its growth. Immediately after publication, other microbiologists and biochemists expressed doubt about this claim, which was robustly criticized in the scientific community. Subsequent independent studies published in 2012 found no detectable arsenate in the DNA of GFAJ-1, refuted the claim, and demonstrated that GFAJ-1 is simply an arsenate-resistant, phosphate-dependent organism.
Jeffrey Bub is a physicist and philosopher of physics, and Distinguished Professor in the department of philosophy, the Joint Center for Quantum Information and Computer Science, and the Institute for Physical Science and Technology at the University of Maryland, College Park.
Julia A. Vorholt is a full professor of microbiology at ETH Zurich and an elected member of the German Academy of Sciences Leopoldina.
Rosemary Jeanne Redfield is a microbiologist associated with the University of British Columbia where she worked as a faculty member in the Department of Zoology from 1993 until retiring in 2021.
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