Digital physics is a speculative idea that the universe can be conceived of as a vast, digital computation device, or as the output of a deterministic or

probabilistic Probability is the branch of mathematics concerning numerical descriptions of how likely an event is to occur, or how likely it is that a proposition is true. The probability of an event is a number between 0 and 1, where, roughly speaking, ...

computer program A computer program is a sequence or set of instructions in a programming language for a computer to execute. Computer programs are one component of software, which also includes documentation and other intangible components. A computer progra ...

. The hypothesis that the

universe The universe is all of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy. The Big Bang theory is the prevailing cosmological description of the development of the universe. A ...

is a

digital computer A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations (computation) automatically. Modern digital electronic computers can perform generic sets of operations known as programs. These progra ...

was proposed by Konrad Zuse in his 1969 book '' Rechnender Raum'' ("''Calculating Space''"). The term ''digital physics'' was coined by Edward Fredkin in 1978, who later came to prefer the term digital philosophy. Fredkin encouraged the creation of a digital physics group at what was then MIT's Laboratory for Computer Science, with Tommaso Toffoli and Norman Margolus as primary figures. ''Digital physics'' suggests that there exists, at least in principle, a program for a universal computer that computes the evolution of the

. The computer could be, for example, a huge

cellular automaton A cellular automaton (pl. cellular automata, abbrev. CA) is a discrete model of computation studied in automata theory. Cellular automata are also called cellular spaces, tessellation automata, homogeneous structures, cellular structures, tess ...

. Extant models of digital physics are incompatible with the existence of several continuous characters of physical symmetries, e.g.,

rotational symmetry Rotational symmetry, also known as radial symmetry in geometry, is the property a shape has when it looks the same after some rotation by a partial turn. An object's degree of rotational symmetry is the number of distinct orientations in which i ...

translational symmetry In geometry, to translate a geometric figure is to move it from one place to another without rotating it. A translation "slides" a thing by . In physics and mathematics, continuous translational symmetry is the invariance of a system of equatio ...

, Lorentz symmetry, and the

Lie group In mathematics, a Lie group (pronounced ) is a group that is also a differentiable manifold. A manifold is a space that locally resembles Euclidean space, whereas groups define the abstract concept of a binary operation along with the addit ...

gauge invariance of Yang–Mills theories, all central to current physical theory. Moreover, extant models of digital physics violate various well-established features of

quantum physics Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, q ...

, belonging to the class of theories with local hidden variables that have so far been ruled out experimentally using Bell's theorem.

See also

References

Further reading