A Tipler Cylinder is a hypothetical cosmological object theorized to be a potential mode of time travel—an approach that is conceivably functional within humanity's current understanding of physics, construction of the device notwithstanding. A hypothesis (= assumption in ancient Greek) is a proposed explanation for a phenomenon. ... Cosmology, from the Greek: κοσμολογία (cosmologia, κόσμος (cosmos) world + λογια (logia) discourse) is the study of the universe in its totality and by extension mans place in it. ... Theory has a number of distinct meanings in different fields of knowledge, depending on the context and their methodologies. ... Time travel is a concept that has long fascinated humanity—whether it is Merlin experiencing time backwards, or religious traditions like Mohammeds trip to Jerusalem and ascent to heaven, returning before a glass knocked over had spilt its contents. ... A black hole concept drawing by NASA. Physics (from the Greek, φυσικός (physikos), natural, and φύσις (physis), nature) is the science of the natural world dealing with the fundamental constituents of the universe, the forces they exert on one another, and the results produced by these forces. ...

Frank J. Tipler suggested in 1974 that if a sufficiently long cylinder with the mass of several neutron stars was induced to spin along its longitudinal axis, the cylinder should create a frame-dragging effect and warp spacetime in its locality as the spin approached the speed of light. A spacecraft traveling either with or against the direction of the spin would travel through time along a Closed Timelike Curve or CTC. Frank J. Tipler is a professor of mathematical physics at Tulane University, New Orleans, physicist, theologian and cornucopian philosopher. ... 1974 (MCMLXXIV) is a common year starting on Tuesday (click on link for calendar). ... A right circular cylinder In mathematics, a cylinder is a quadric, i. ... Mass is a property of physical objects that, roughly speaking, measures the amount of matter they contain. ... Neutron stars are one of the few possible endpoints of stellar evolution. ... The word axis has several meanings: In mathematics, axis can mean: A straight line around which a geometric figure can be rotated. ... According to Albert Einsteins theory of general relativity, space and time get pulled out of shape near a rotating body in a phenomenon referred to as frame-dragging. ... World line of the orbit of the Earth depicted in two spatial dimensions X and Y (the plane of the Earth orbit) and a time dimension, usually put as the vertical axis. ... The terms spin and SPIN have several meanings, including those primarily discussed as spinning: For spin in sub-atomic physics, see spin (physics) For the stalled aircraft maneuver or any of several forms of loss of control in aircraft, see spin (flight) For the periodical, see Spin Magazine For the... Cherenkov effect in a swimming pool nuclear reactor. ... Ariane 5 lifts off with the Rosetta space probe on March 2, 2004. ... From the point of view of general relativity, a closed timelike curve (CTC) is a worldline of a material particle in spacetime that is closed. ...

CTC's are associated, in Lorentzian manifolds which are interpreted physically as spacetimes, with causal anomalies such as going back in time and shooting your own grandfather. They have an unnerving habit of appearing in some of the most important exact solutions in general relativity, including the Kerr vacuum (which models a rotating black hole) and the van Stockum dust (which models a cylindrically symmetrical configuration of rotating pressureless fluid or dust). In differential geometry, a pseudo-Riemannian manifold is a smooth manifold equipped with a smooth, symmetric, tensor which is nondegenerate at each point on the manifold. ... World line of the orbit of the Earth depicted in two spatial dimensions X and Y (the plane of the Earth orbit) and a time dimension, usually put as the vertical axis. ... The grandfather paradox is a paradox of time travel, supposedly first conceived by the science fiction writer René Barjavel in his book Future times three (Le voyageur imprudent, 1943). ... In general relativity, the Kerr metric describes the geometry of spacetime around a rotating massive body, such as a rotating black hole. ... In general relativity, the van Stockum dust is an exact solution of the Einstein field equation in which the gravitational field is generated by dust particles which are rotating about an axis of cylindrical symmetry. ... In general relativity, a dust solution is an exact solution of the Einstein field equation in which the gravitational field is produced entirely by the mass, momentum, and stress density of a perfect fluid which has positive mass density but vanishing pressure. ...

Some physicists argue that since Tipler Cylinders allow Closed Timelike Curves they violate Roger Penrose's cosmic censorship hypothesis, as naked singularities would be visible. Others argue that since causality is not built into Einstein's field equation, these regions may actually be able to exist (see also Godel's universe). A physicist is a scientist trained in physics. ... Roger Penrose Sir Roger Penrose, OM, FRS (born 8 August 1931) is an English mathematical physicist and Emeritus Rouse Ball Professor of Mathematics at the University of Oxford. ... This article is in need of attention from an expert on the subject. ... blah blah blah, some people believe God made the universe and that is all there is. ... Although causality, the relationship between causes and effects, is often examined in the fields of philosophy, computer science, and statistics, it has a place in the study of physics as well. ... In physics, the Einstein field equation or Einstein equation is a differential equation in Einsteins theory of general relativity. ... In mathematics, the constructible universe (or Gödels constructible universe), denoted , is a particular class of sets which can be described entirely in terms of simpler sets. ...

A limitation of the Tipler Cylinder is that it is only possible to travel to times (and places) in which the cylinder already exists. Thus, one could not travel backwards further than the date that the cylinder was activated, nor beyond a point after which the cylinder was destroyed (assuming such destruction is even possible). One could hypothesize that this is why humans have not yet encountered a time traveler. [[{{{diversity_link}}}|Diversity]] {{{diversity}}} Binomial name Homo sapiens Linnaeus, 1758 Trinomial name {{{trinomial}}} Type Species {{{type_species}}} Subspecies Homo sapiens idaltu (extinct) Homo sapiens sapiens [[Image:{{{range_map}}}|{{{range_map_width}}}|]] Synonyms {{{synonyms}}} Homo (genus). ...

Though Tipler's paper originally suggested that the cylinder might have to be of infinite length, later calculations indicated that the model would function if it were "only" a few thousand kilometers long. In scientific publishing, a paper is a scientific article that is published in a scientific journal. ... Infinity is a word carrying a number of different meanings in mathematics, philosophy, theology and everyday life. ... In general English usage, length (symbols: l, L) is but one particular instance of distance – an objects length is how long the object is – but in the physical sciences and engineering, the word length is in some contexts used synonymously with distance. Height is vertical distance; width (or breadth... A calculation is a deliberate process for transforming one or more inputs into one or more results. ... A kilometre (American spelling: kilometer) (symbol: km) is a unit of length equal to 1000 metres (from the Greek words khilia = thousand and metro = count/measure). ...

Tipler Cylinders in fiction

• John DeChancie's Starrigger series uses vertically-aligned Tipler Cylinders (officially called Kerr-Tipler objects) to create spacetime gateways along an intergalactic highway.
• The C°ntinuum role-playing game postulates the use of Tipler Cylinders for "deep" time travel such as to the end of the universe.
• Larry Niven wrote a short story (whose titled, he admitted, borrowed from Tipler's paper) in which the Tipler Cylinder was known to be a functional mode of time travel, but any race that tried to build one saw their work destroyed by a natural disaster before the Cylinder was complete.
• Poul Anderson in The Avatar.
• The Astranagant in Super Robot Wars uses time-based weaponry inspired by the Tipler Cylinder.
• In Terry Pratchett's Discworld series the History Monks use Procrastinators, rotating stone cylinders that are an obvious spoof of Tipler Cylinders, to move amounts of time around and fix temporal disturbances.

John DeChancie is an American author. ... Cover of the main rulebook C°ntinuum: roleplaying in The Yet is a science fiction role-playing game about time travel created by Chris Adams, Dave Fooden and Barbara Manui and published by Aetherco/Dreamcatcher. ... A role-playing game (RPG) is a type of game in which players assume the roles of characters and collaboratively create narratives. ... Many religions have postulated an end to the Universe. ... Larry Niven Laurence van Cott Niven (born April 30, 1938) is a US science fiction author. ... This article is in need of attention. ... A natural disaster is a catastrophe that occurs when a hazardous physical event (such as a volcanic eruption, earthquake, landslide, hurricane, or any of the other natural phenomena listed below) precipitates extensive damage to property, a large number of casualties, or both. ... Poul William Anderson (November 25, 1926 – July 31, 2001) was a prolific science fiction author of the genres Golden Age; some of his short stories were first published using the pseudonyms A. A. Craig, Michael Karageorge, and Winston P. Sanders. Poul Anderson also wrote fantasy such as the King... Astranagant Astranagant(アストラナガン) is a fictional giant robot from the Japanese video game series Super Robot Wars. ... Super Robot Wars: Alpha Gaiden, one of many SRW games released by Banpresto in Japan. ... Terence David John Pratchett OBE is an English fantasy author (born April 28, 1948, in Beaconsfield, Buckinghamshire, England), best known for his Discworld series. ... The Discworld is a series of 35 humorous fantasy novels and a number of shorter works by Terry Pratchett set on the Discworld. ... The Order of Wen the Eternally Surprised, better known as the History Monks, and also sometimes referred to as the Men In Saffron (see Men in Black) and No Such Monastery (see NSA), is a highly secretive religious organisation in the Discworld novels of Terry Pratchett, based in the Monastery...

References

• Tipler, Frank J. "Rotating Cylinders and the Possibility of Global Causality Violation." Physical Review D 9 (1974): 2203-2206.
• Penrose, Roger. "The Question of Cosmic Censorship." Journal of Astrophysics and Astronomy Vol. 20 (September, 1999): 233.
• Robert, Wald (ed). Black Holes and Relativistic Stars. University of Chicago Press, 1998. ISBN 0226870340