David Deutsch

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:

1. Hugh Everett's many-worlds interpretation of quantum physics, "the first and most important of the four strands."
2. 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.
3. 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.")
4. 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]".[14]

"A bad explanation is easy to vary."[14]^{: minute 11:22}

"The search for hard-to-vary explanations is the origin of all progress"[14]^{: minute 15:05}

"That the truth consists of hard-to-vary assertions about reality is the most important fact about the physical world."[14]^{: 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 around 1900 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).[15]

Deutsch's second book, The Beginning of Infinity: Explanations that Transform the World, was published on 31 March 2011. In this book, he views the European Enlightenment of the 17th and 18th centuries as near the beginning of a potentially unending sequence of purposeful knowledge creation. He examines the nature of knowledge, memes, and how and why creativity evolved in humans.

The Fabric of Reality was shortlisted for the Rhone-Poulenc science book award in 1998.[16] Deutsch was awarded the Dirac Prize of the Institute of Physics in 1998,[17] and the Edge of Computation Science Prize in 2005.[17][18] In 2017, he received the Dirac Medal of the International Centre for Theoretical Physics (ICTP).[19] 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.[4] In 2020 he was awarded an Honorary Fellowship of the Cybernetics Society.[20] In 2018, he received the Micius Quantum Prize. In 2021, he was awarded the Isaac Newton Medal and Prize.[21]

On 22 September 2022, he was awarded the Breakthrough Prize in Fundamental Physics (sharing it with 3 others).[22]