David Elieser Deutsch
18 May 1953 
|Education||William Ellis School|
Clare College, Cambridge (BA)|
Wolfson College, Oxford (PhD)
Quantum information science
University of Oxford|
|Thesis||Boundary effects in quantum field theory (1978)|
|Doctoral students||Artur Ekert |
David Elieser Deutsch  ( // DOYTCH; born 18 May 1953)  is a British physicist at the University of Oxford. He is a Visiting Professor in the Department of Atomic and Laser Physics at the Centre for Quantum Computation (CQC) in the Clarendon Laboratory of the University of Oxford. He pioneered the field of quantum computation by formulating a description for a quantum Turing machine, as well as specifying an algorithm designed to run on a quantum computer.  He has also proposed the use of entangled states and Bell's theorem for quantum key distribution  and is a proponent of the many-worlds interpretation of quantum mechanics. 
Deutsch was born into a Jewish family in Haifa in Israel on 18 May 1953, the son of Oskar and Tikva Deutsch. David attended Geneva House school in Cricklewood (his parents owned and ran the Alma restaurant on Cricklewood Broadway, NW2), followed by The William Ellis School in Highgate (then a voluntary aided school in north London) before reading Natural Sciences at Clare College, Cambridge and taking Part III of the Mathematical Tripos. He went on to Wolfson College, Oxford for his doctorate in theoretical physics  and wrote his thesis on quantum field theory in curved space-time   supervised by Dennis Sciama  and Philip Candelas.  
His work on quantum algorithms began with a 1985 paper, later expanded in 1992 along with Richard Jozsa to produce the Deutsch–Jozsa algorithm, one of the first examples of a quantum algorithm that is exponentially faster than any possible deterministic classical algorithm.  In his 1985 paper, he also suggests the use of entangled states and Bell's theorem for quantum key distribution.  In his nomination for election as a Fellow of the Royal Society (FRS) in 2008, his contributions were described as: 
"[having] laid the foundations of the quantum theory of computation, and has subsequently made or participated in many of the most important advances in the field, including the discovery of the first quantum algorithms, the theory of quantum logic gates and quantum computational networks, the first quantum error-correction scheme, and several fundamental quantum universality results. He has set the agenda for worldwide research efforts in this new, interdisciplinary field, made progress in understanding its philosophical implications (via a variant of the many-universes interpretation) and made it comprehensible to the general public, notably in his book The Fabric of Reality."
Since 2012,  he has been working on constructor theory, an attempt at generalizing the quantum theory of computation to cover not just computation but all physical processes.   Together with Chiara Marletto, he published a paper in December 2014 entitled Constructor theory of information, that conjectures that information can be expressed solely in terms of which transformations of physical systems are possible and which are impossible.  
In his 1997 book The Fabric of Reality, Deutsch details his "Theory of Everything". It aims not at the reduction of everything to particle physics, but rather mutual support among multiversal, computational, epistemological, and evolutionary principles. His theory of everything is somewhat emergentist rather than reductive. There are four strands to his theory:
- Hugh Everett's many-worlds interpretation of quantum physics, "the first and most important of the four strands."
- Karl Popper's epistemology, especially its anti-inductivism and requiring a realist (non-instrumental) interpretation of scientific theories, as well as its emphasis on taking seriously those bold conjectures that resist falsification.
- Alan Turing's theory of computation, especially as developed in Deutsch's Turing principle, in which the Universal Turing machine is replaced by Deutsch's universal quantum computer. ("The theory of computation is now the quantum theory of computation.")
- Richard Dawkins' refinement of Darwinian evolutionary theory and the modern evolutionary synthesis, especially the ideas of replicator and meme as they integrate with Popperian problem-solving (the epistemological strand).
In a 2009 TED talk, Deutsch expounded a criterion for scientific explanation, which is to formulate invariants: "State an explanation [publicly, so that it can be dated and verified by others later] that remains invariant [in the face of apparent change, new information, or unexpected conditions]". 
- "A bad explanation is easy to vary." :minute 11:22
- "The search for hard-to-vary explanations is the origin of all progress" :minute 15:05
- "That the truth consists of hard-to-vary assertions about reality is the most important fact about the physical world." :minute 16:15
Invariance as a fundamental aspect of a scientific account of reality had long been part of philosophy of science: for example, Friedel Weinert's book The Scientist as Philosopher (2004) noted the presence of the theme in many writings from the turn of the 20th century onward, such as works by Henri Poincaré (1902), Ernst Cassirer (1920), Max Born (1949 and 1953), Paul Dirac (1958), Olivier Costa de Beauregard (1966), Eugene Wigner (1967), Lawrence Sklar (1974), Michael Friedman (1983), John D. Norton (1992), Nicholas Maxwell (1993), Alan Cook (1994), Alistair Cameron Crombie (1994), Margaret Morrison (1995), Richard Feynman (1997), Robert Nozick (2001), and Tim Maudlin (2002). 
Deutsch's second book, The Beginning of Infinity: Explanations that Transform the World, was published on 31 March 2011. In this book, Deutsch views the Enlightenment of the 18th century as near the beginning of a potentially unending sequence of purposeful knowledge creation. He examines the nature of memes and how and why creativity evolved in humans. 
The Fabric of Reality was shortlisted for the Rhone-Poulenc science book award in 1998.  Deutsch was awarded the Dirac Prize of the Institute of Physics in 1998,  and the Edge of Computation Science Prize in 2005.   In 2017, he received the Dirac Medal of the International Centre for Theoretical Physics (ICTP).  Deutsch is linked to Paul Dirac through his doctoral advisor Dennis Sciama, whose doctoral advisor was Dirac. Deutsch was elected a Fellow of the Royal Society (FRS) in 2008.  In 2020 he was awarded an Honorary Fellowship of the Cybernetics Society.  In 2018, he received the Micius Quantum Prize.
|Wikiquote has quotations related to: David Deutsch|
- "Deutsch, Prof. David Elieser". Who's Who. ukwhoswho.com. 2014 (April 2014 online ed.). A & C Black, an imprint of Bloomsbury Publishing plc. Retrieved 26 July 2014. (subscription or UK public library membership required)
- David Deutsch at the Mathematics Genealogy Project
- Deutsch, David Elieser (1978). Boundary effects in quantum field theory. bodleian.ox.ac.uk (DPhil thesis). University of Oxford. EThOS uk.bl.ethos.453518.
- Deutsch, David (31 March 2011). The beginning of infinity: explanations that transform the world. Allen Lane. ISBN 9780713992748.
- Peach, Filiz (2000). "David Deutsch". Philosophy Now. Interview. Retrieved 7 December 2016.
- Anon (2008).
"Professor David Deutsch FRS". royalsociety.org. London:
Royal Society. One or more of the preceding sentences incorporates text from the royalsociety.org website where:
"All text published under the heading 'Biography' on Fellow profile pages is available under Creative Commons Attribution 4.0 International License.” -- "Royal Society Terms, conditions and policies". Archived from the original on 11 November 2016. Retrieved 9 March 2016.CS1 maint: bot: original URL status unknown ( link)
- Deutsch, David (1985). "Quantum theory, the Church-Turing principle and the universal quantum computer". Proceedings of the Royal Society A. 400 (1818): 97–117. Bibcode: 1985RSPSA.400...97D. CiteSeerX 10.1.1.41.2382. doi: 10.1098/rspa.1985.0070. S2CID 1438116.
- David Deutsch publications indexed by the Scopus bibliographic database. (subscription required)
- Deutsch, David; Candelas, Philip (1979). "Boundary effects in quantum field theory". Physical Review D. 20 (12): 3063–3080. Bibcode: 1979PhRvD..20.3063D. doi: 10.1103/physrevd.20.3063.
- Merali, Zeeya (26 May 2014). "A Meta-Law to Rule Them All: Physicists Devise a "Theory of Everything"". Scientific American. Nature Publishing Group. Retrieved 11 January 2016.
- Heaven, Douglas (6 November 2012). "Theory of everything says universe is a transformer". New Scientist. Retrieved 11 January 2016.
- Anon (2012). "Constructor Theory: A Conversation with David Deutsch". edge.org.
- Deutsch, D.; Marletto, C. (2014). "Constructor theory of information". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 471 (2174): 20140540. arXiv: 1405.5563. Bibcode: 2014RSPSA.47140540D. doi: 10.1098/rspa.2014.0540. ISSN 1364-5021. PMC 4309123. PMID 25663803.
- Deutsch, D. and Marletto, C.; "Why we need to reconstruct the universe", New Scientist, 24 May 2014, pages 30–31.
- Deutsch, David (October 2009). A new way to explain explanation. TED talk. Also available from YouTube.CS1 maint: postscript ( link)
- Weinert, Friedel (2004). "Invariance and reality". The Scientist as Philosopher: Philosophical Consequences of Great Scientific Discoveries. Berlin; New York: Springer-Verlag. pp. 62–74 (72). doi: 10.1007/b138529. ISBN 3540205802. OCLC 53434974.
- David Deutsch at TED
- Deutsch, David. "The Fabric of Reality". daviddeutsch.org.uk. Retrieved 7 December 2016.
- Deutsch, David (2016). "About Me". daviddeutsch.org.uk. Retrieved 7 December 2016.
- Edge of Computation Science Prize Archived 9 December 2006 at the Wayback Machine
- "Dirac Medal of ICTP 2017". ictp.it.
- David Deutsch entry, Celeb atheists website, 30 March 2005. Accessed Jan 2015
- Friedman, Dawn (2003). "Taking Children Seriously: A new child-rearing movement believes parents should never coerce their kids". UTNE Reader. Ogden Publications, Inc. Retrieved 7 December 2016.