Digital physics

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Comparison of two cellular automata . In 1969 Konrad Zuse published his book “Computing Space”, in which he assumes that the laws of nature follow discrete rules and that everything that happens in the universe is the result of the work of a gigantic cellular automaton. The book represents the basis of the considerations in digital physics.

Digital physics (also digital ontology or digital philosophy ) refers to theoretical perspectives in physics , natural theory and also in cosmology , which are based on the premise that the universe can be described by information . According to these theories, the universe can be described by the output of a deterministic or probabilistic computer program. The term "digital physics" was first mentioned by Edward Fredkin ; later he preferred the term "digital philosophy".

Origins

Rule 110, a Turing-complete , cellular automaton.
One of the most elementary processes in Zuse's computing space: two digital particles A and B form a new digital particle C.
Conway's Game of Life contains interacting and moving objects that come close to Zuse's idea of ​​“digital particles”.

The hypothesis that the universe can be understood as a digital machine came to Konrad Zuse during a stay in Hinterstein in 1945/1946 and was published by him in 1969 in the book Rechnender Raum . In it, he formalized his ideas on “computing space”, based on Stanisław Marcin Ulam's work on cellular automata from around 1940. In Zuse's computing space, all numerical values ​​in the universe are finite and discrete. He pursues the idea of ​​a fundamental digitization of reality, with which he further generalizes the idea of ​​quantizing physical quantities. The core elements of his digital universe are spatially limited structures that are propagated in calculating space. He called them digital particles based on elementary particles . The set of rules according to which digital particles interact is given by the interconnection of the computing space, the original circuit. Konrad Zuse already articulated two core problems of this approach: The computing space is an excellent reference system and not consistent with the theory of relativity . In addition, it does not allow spooky action at a distance .

In the 1950s, Carl Friedrich von Weizsäcker developed the concept of describing nature within the framework of a quantum theory of information , which led to the quantum theory of the original alternatives . Due to its abstract nature, it has not yet been possible to develop it into a full physical theory. In contrast to other approaches, his theory is based on epistemological considerations, in which the information units (so-called Ure ) are viewed as a certain type of representation of objective reality. In addition, as fundamental entities, it only contains time with its specific structure and the original alternatives from which the entire reality is constituted. His theory does not require elementary spatial cells or vertices between which information is exchanged and is therefore essentially non-local , i.e. independent of any field-theoretical requirements. In this sense, its physical concept of reality is even more fundamentally related to the concept of information in the sense of quantum theory and must be distinguished from other approaches.

Every computer must also be compatible with the principles of information theory , statistical mechanics and quantum mechanics . A basic connection between these areas was described in two articles in 1957 by Edwin Thompson Jaynes . In addition, Jaynes worked out an interpretation of probability theory as a generalized Aristotelian logic . This view is very useful for linking basic physics with digital computers, as these are designed to implement operations from classical logic and Boolean algebra .

Authors and representatives of the new generation

Other authors and representatives of digital physics who describe the universe as a computer are Stephen Wolfram , Jürgen Schmidhuber and Nobel Prize winner Gerard 't Hooft . These authors believe that the seemingly probabilistic nature of quantum physics is compatible with the idea of ​​predictability. Of course, the thesis that the universe is a digital computer is basically to be understood only as an analogy to symbolize the meaning of the concept of information in the description of physical reality. The critical awareness of the metaphorical character of the comparison with a computer does not contradict the fact that one can try to determine the information content of the universe very concretely. In his estimate from the 1960s, Carl Friedrich von Weizsäcker arrived at something like binary information units as part of his theory of the original alternatives . In his essay “The Computational Universe” , Seth Lloyd calculates the computing power and information content of the universe to be approximately to operations or bits since its inception. His result thus corresponds quantitatively to von Weizsacker's view.

Newer theories describing digital physics at the quantum level have been published by David Deutsch and Paola Zizzi. Similar ideas are the “pancomputationalism”, the “computational universe” theory, John Archibald Wheeler's It from Bit and Max Tegmark's “Mathematical Universe” hypothesis (Ultimate Ensemble) .

See also

literature

Books

Essays

Web links

Individual evidence

  1. ^ Matthew Cook: Universality in Elementary Cellular Automata . In: Complex Systems . 15, No. 1, 2004, ISSN  0891-2513 .
  2. ↑ Stephen Wolfram, A New Kind of Science, p.169, 675-691.
  3. ↑ a b Konrad Zuse: Computing Space , Spectrum of Science, reprint in the March 2007 edition: "Is the universe a computer?".
  4. ↑ Konrad Zuse: The computer - my life's work . 3. Edition. Springer, Berlin 1993, ISBN 3-540-56292-3 . P. 93.
  5. ↑ Carl Friedrich von Weizsäcker: The unity of nature. Carl Hanser Verlag, 1971.
  6. ^ Carl Friedrich von Weizsäcker: Structure of Physics. Carl Hanser Verlag, 1985.
  7. ^ Carl Friedrich von Weizsäcker: Time and knowledge. Carl Hanser Verlag, 1992.
  8. ^ ET Jaynes: Information Theory and Statistical Mechanics. In: Physical Review. 106, 1957, p. 620, doi: 10.1103 / PhysRev.106.620 .
  9. ^ ET Jaynes: Information Theory and Statistical Mechanics. II. In: Physical Review. 108, 1957, p. 171, doi: 10.1103 / PhysRev.108.171 .
  10. ↑ Jaynes, ET, 1990: Probability Theory as Logic (PDF) , in Fougere, PF, ed., Maximum-Entropy and Bayesian Methods . Boston: Kluwer.
  11. ^ A New Kind of Science website. Reviews of ANKS.
  12. ↑ Schmidhuber, J .: Computer Universes and an Algorithmic Theory of Everything ; arxiv : 1501.01373 .
  13. ^ G. 't Hooft, 1999: Quantum Gravity as a Dissipative Deterministic System , Class. Quant. Grav. 16 : 3263-3279, arxiv : gr-qc / 9903084 ; On discrete physics and a list of 't Hooft's recent works.
  14. ^ Seth Lloyd: Computational Capacity of the Universe. In: Physical Review Letters. 88, 2002, doi: 10.1103 / PhysRevLett.88.237901 . arxiv : quant-ph / 0110141v1 .
  15. ^ Lloyd, S .: The Computational Universe: Quantum gravity from quantum computation. arxiv : quant-ph / 0501135v5 .
  16. ^ Zizzi, Paola: Spacetime at the Planck Scale: The Quantum Computer View. arxiv : gr-qc / 0304032 .
  17. ^ Rudolf Germer , academia.edu , accessed on October 31, 2017
  18. ↑ arxiv : nlin / 0501022v3 and arxiv : 1206.2060v1 [nlin.cg]