Is Space Digital?

via Scientific American

The Nature of Space and Time...

    Space may not be smooth and continuous. Instead it may be digital, composed of tiny bits. Physicists have assumed that these bits are far too small to measure with current technology.

    Yet one scientist thinks that he has devised a way to detect the bitlike structure of space. His machine—at present under construction—will attempt to measure its grainy nature.

    The experiment is one of the first to investigate the principle that the universe emerges from information—specifically, information that is imprinted on two-dimensional sheets.

    If successful, the experiment will shift the foundations of what we know about space and time, providing a glimpse of a new physics that could supplant our existing understanding.

http://www.nature.com/scientificamerican/journal/v23/n3s/full/scientificamericanuniverse0814-104.html

Zuse's Thesis: The Universe is a Computer

Konrad Zuse (1910-1995; pronounce: “Conrud Tsoosay”) not only built the first programmable computers (1935-1941) and devised the first higher-level programming language (1945), but also was the first to suggest (in 1967) that the entire universe is being computed on a computer, possibly a cellular automaton (CA). He referred to this as “Rechnender Raum” or Computing Space or Computing Cosmos. Many years later similar ideas were also published / popularized / extended by Edward Fredkin (1980s), Jürgen Schmidhuber (1990s – see overview), and more recently Stephen Wolfram (2002). Zuse’s first paper on digital physics and CA-based universes was:

Konrad Zuse, Rechnender Raum, Elektronische Datenverarbeitung, vol. 8, pages 336-344, 1967. Download PDF scan.

Zuse is careful: on page 337 he writes that at the moment we do not have full digital models of physics, but that does not prevent him from asking right there: which would be the consequences of a total discretization of all natural laws? For lack of a complete automata-theoretic description of the universe he continues by studying several simplified models. He discusses neighbouring cells that update their values based on surrounding cells, implementing the spread and creation and annihilation of elementary particles. On page 341 he writes “In all these cases we are dealing with automata types known by the name “cellular automata” in the literature” and cites von Neumann’s 1966 book: Theory of self-reproducing automata. On page 342 he briefly discusses the compatibility of relativity theory and CAs.

Contrary to a widely spread misunderstanding, quantum physics, quantum computation, Heisenberg’s uncertainty principle and Bell’s inequality do not provide any physical evidence against Zuse’s thesis of a CA-computed universe! Gerard t’ Hooft (Physics Nobel 1999) in principle agrees with determinism a la Zuse: proof by authority :-)

Continue Reading:

Digital Philosophy

http://www.digitalphilosophy.org/

What is Digital Philosophy?

Digital Philosophy (DP) is a new way of thinking about the fundamental workings of processes in nature. DP is an atomic theory carried to a logical extreme where all quantities in nature are finite and discrete. This means that, theoretically, any quantity can be represented exactly by an integer. Further, DP implies that nature harbors no infinities, infinitesimals, continuities, or locally determined random variables. This paper explores Digital Philosophy by examining the consequences of these premises.

At the most fundamental levels of physics, DP implies a totally discrete process called Digital Mechanics. Digital Mechanics[1] (DM) must be a substrate for Quantum Mechanics. Digital Philosophy makes sense with regard to any system if the following assumptions are true:

All the fundamental quantities that represent the state information of the system are ultimately discrete. In principle, an integer can always be an exact representation of every such quantity. For example, there is always an integral number of neutrons in a particular atom. Therefore, configurations of bits, like the binary digits in a computer, can correspond exactly to the most microscopic representation of that kind of state information.

In principle, the temporal evolution of the state information (numbers and kinds of particles) of such a system can be exactly modeled by a digital informational process similar to what goes on in a computer. Such models are straightforward in the case where we are keeping track only of the numbers and kinds of particles. For example, if an oracle announces that a neutron decayed into a proton, an electron, and a neutrino, it’s easy to see how a computer could exactly keep track of the changes to the numbers and kinds of particles in the system. Subtract 1 from the number of neutrons, and add 1 to each of the numbers of protons, electrons, and neutrinos.

The possibility that DP may apply to various fields of science motivates this study.