In the history of science, Laplace's demon is a hypothetical "demon" envisioned in 1814 by Pierre-Simon Laplace such that if it knew the precise location and momentum of every atom in the universe then it could use Newton's laws to reveal the entire course of cosmic events, past and future. Science is a body of empirical and theoretical knowledge, produced by a global community of researchers, making use of specific techniques for the observation and explanation of real phenomena, this techne summed up under the banner of scientific method. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Newtons laws of motion are the three scientific laws which Isaac Newton discovered concerning the behaviour of moving bodies. ...

Original quote

Laplace strongly believed in causal determinism, which is expressed in the following quote from the introduction to the Essai: Put simply, causal determinism expresses the belief that every effect has a cause, and therefore science, pursued diligently enough, will explain all natural phenomena and thus produce a TOE (Theory of Everything). ...

This intellect is often referred to as Laplace's demon. Note, however, that the description of the hypothetical intellect described above by Laplace as a demon does not come from Laplace, but from later biographers: Laplace saw himself as a scientist that hoped that humanity would progress in a better scientific understanding of the world, which, if and when eventually completed, would still need a tremendous calculating power to compute it all in a single instant. While Laplace saw foremost practical problems for mankind to reach this ultimate stage of knowledge and computation, later interpretations of quantum mechanics, which were adopted by philosophers defending the existence of free will, also leave the theoretical possibility of such an "intellect" contested. Universe is a word derived from the Old French univers, which in turn comes from the Latin roots unus (one) and versus (a form of vertere, to turn). Based on observations of the observable universe, physicists attempt to describe the whole of space-time, including all matter and energy and... The past is the portion of the timeline that has already occurred; it is the opposite of the future. ... Look up Future in Wiktionary, the free dictionary. ... In physics, a net force acting on a body causes that body to accelerate; that is, to change its velocity. ... It has been suggested that this article or section be merged with Daemon (mythology). ... In a nontechnical sense, an interpretation of quantum mechanics is an attempt to answer the question: what exactly is quantum mechanics talking about? Quantum mechanics has been very successful in predicting experimental results. ... A philosopher is a person who thinks deeply regarding people, society, the world, and/or the universe. ... Free-Will is a Japanese independent record label founded in 1986. ...

The demon's downfall

It should be noted that the existence in principle of this hypothetical "intellect" depends on a number of assumptions, all of which are highly speculative:

1. It is possible to know all the information about the past and present states of the universe. (contra both Quantum Mechanics and Relativity)
2. It is possible to know all the natural laws governing the universe.
3. These natural laws are fully deterministic, computable and do not underdetermine the physical outcomes.
4. That an "intellect" could be capable of computing the future states of the universe faster than they actually occur.
5. That such an intellect could exist without being inside the universe (contra Materialism).^[1]
6. That such knowledge not change or alter the universe in such a way that the state of the universe would change.

John Polkinghorne FRS argues strongly as a physicist that nature is cloud-like rather than clock-like and points out that, apart from any other problems, uncertainty about the exact position of an electron the other side of the universe would be sufficient to invalidate a calculation about the position of an O₂ molecule in air after 50 collisions with its neighbours (i.e. in about 0.1 ns), even if they were solely influenced by Newton's laws.^[2] Fig. ... Two-dimensional analogy of space-time curvature described in General Relativity. ... In philosophy, materialism is that form of physicalism which holds that the only thing that can truly be said to exist is matter; that fundamentally, all things are composed of material and all phenomena are the result of material interactions. ... John Polkinghorne, KBE, FRS, PhD, ScD, MA, (born October 16, 1930 in Weston-super-Mare, England) is a British particle physicist and theologian. ... FRS is an abbreviation which can stand for various phrases: Family Radio Service, a personal radio service utilizing the UHF band Fellow of the Royal Society, a title awarded to distinguished scientists who are British, Commonwealth or Republic of Ireland citizens Fisheries Research Services, an agency of the Scottish Executive...

According to chemical engineer Robert Ulanowicz, in his 1986 book Growth and Development, Laplace's demon met its end with early 19th century developments of the concepts of irreversibility, entropy, and the second law of thermodynamics. In other words, Laplace's demon was based on the premise of reversibility and classical mechanics; thermodynamics, i.e. real processes, however, are irreversible. Robert E. Ulanowicz (b. ... Irreversibility is that property of an event which makes reverting back to the state before the occurrence of the event impossible. ... Ice melting - classic example of entropy increasing[1] described in 1862 by Rudolf Clausius as an increase in the disgregation of the molecules of the body of ice. ... The second law of thermodynamics is an expression of the universal law of increasing entropy. ... In thermodynamics, a reversible process (or reversible cycle if the process is cyclic) is a process that can be reversed by means of infinitesimal changes in some property of the system. ...

Recent views

There has recently been proposed a limit on the computational power of the universe, i.e. the ability of Laplace's Demon to process an infinite amount of information. The limit is based on the maximum entropy of the universe, the speed of light, and the minimum amount of time taken to move information across the Planck length, and the figure turns out to be 2¹³⁰ bits^{[citation needed]}. Accordingly, anything that requires more than this amount of data cannot be computed in the amount of time that has lapsed so far in the universe. (An actual theory of everything might find an exception to this limit, of course.) The Planck length, denoted by , is the unit of length in the system of units known as Planck units. ... This article or section is in need of attention from an expert on the subject. ...

Laplace's demon in popular culture

While the name isn't mentioned, the concept is pretty much the same. In The Hitchhiker's Guide to the Galaxy, a piece of technology is called the Total Perspective Vortex which is stated by the Guide "...since every piece of matter in the Universe is in someway affected by every other piece of matter in the Universe, it is in theory possible to extrapolate the whole of creation — every Galaxy, every sun, every planet, their orbits, their composition, and their economic and social history from, say, one small piece of fairy cake." The cover of the first novel in the Hitchhikers series, from a late 1990s printing. ... The Total Perspective Vortex, in the fictional world of Douglas Adamss The Hitchhikers Guide to the Galaxy, is the most horrible torture device to which a sentient being can be subjected. ...

Douglas Adams, the author of the book and the series, was knowledgeable in science and may very well have used this theory in his book. Douglas Noël Adams (11 March 1952 – 11 May 2001) was an English author, comic radio dramatist, and musician. ...

In Adam Fawers "Improbable: A Novel", the main character becomes a personification Laplace's demon.

A character using the name Laplace no Ma (literally Laplace's Demon) is featured in the second series of the Rozen Maiden anime series. Serialized in Monthly Comic Birz Original run September 2002 – on hiatus No. ...

Laplace No Ma (Laplace's Demon) is a 1993 Videogame for the SNES. 1993 (MCMXCIII) was a common year starting on Friday of the Gregorian calendar and marked the Beginning of the International Decade to Combat Racism and Racial Discrimination (1993-2003). ... A computer game is a game composed of a computer-controlled virtual universe that players interact with in order to achieve a defined goal or set of goals. ... The Super Nintendo Entertainment System, also known as Super Nintendo, Super NES or SNES, is a 16-bit video game console released by Nintendo in North America, Brazil, Europe, and Australia. ...

The Masoukishin Cybuster from the Super Robot Wars metaseries possesses the 'Laplace's Demon Computer' which gives it the ability to predict the future as well as editing or rewriting the entire time line itself. The Cybuster (サイバスター) is an original mecha which originated in the Banpresto strategy Role Playing Game series Super Robot Wars. ... Super Robot Wars: Alpha Gaiden, one of many SRW games released by Banpresto in Japan. ...

References

1. ^ If this "intellect" existed in the universe it would have to be able to model itself. This would not only require the information content of the intellect (and the universe) to be infinite, which is deeply problematic, it would require the "intellect" to predict its own actions faster than they occur, which is a contradiction
2. ^ see e.g. John Polkinghorne Quarks, Chaos and Christianity pp. 65–66

John Polkinghorne, KBE, FRS, PhD, ScD, MA, (born October 16, 1930 in Weston-super-Mare, England) is a British particle physicist and theologian. ...

See also

• Maxwell's demon