M Theory Visionists - Van Stokum Cylinder (Sol's Time Travelling Guide of Mandalics Origins)

Van Stokum Cylinder (Sol's Time Travelling Guide of Mandalics Origins)

Sol - Feb 4, 2004 6:18 pm

Edited Sep 11, 2004 4:09 pm

A time machine based on an immense cylinder spinning at near-light speed. The physicist W. J. van Stokum realized in 1937 that such an object would effectively stir spacetime as if it were treacle, dragging it along as the cylinder turned. What van Stokum didn't realize is that circumnavigating such a cylinder can lead to closed time-like paths. Anyone orbiting the cylinder in the direction of the spin would be caught in the current and, from the perspective of a distant observer, exceed the speed of light and thus travel back in time. Circling the cylinder in the other direction with just the right trajectory would project the subject into the future. The van Stokum time machine is based on the Lense-Thiring effect and uses ordinary matter but of enormous density - many orders of magnitude greater than that of nuclear matter.

http://www.daviddarling.info/encyclopedia/V/vanStokum_cylinder.html

Sol

- Feb 4, 2004 7:23 pm (#1 of 38)

Edited Feb 6, 2004 10:28 pm

Will UConn physicist Ronald Mallett build the first time machine?

Imagine then--and put aside the engineering problems for a moment--a machine big enough to walk into. As you would walk forward within the confines of the light beam, (see diagram below) you'd have the impression of moving forward, but because of the space-time vortex, you'd actually be moving backward. You could walk back through time--maybe even passing yourself as you entered the ring.

http://www.walterzeichner.com/thezfiles/timetravel.html

Return to Solidifing the Experience

Sol

- Feb 4, 2004 7:28 pm (#2 of 38)

Weak gravitational field of the electromagnetic radiation

Ronald L. Mallett Department of Physics, 2152 Hillside Road and UniÍersity of Connecticut, Storrs, CT 06269, USA Received 19 January 2000; accepted 3 April 2000 Communicated by P.R. Holland

Abstract The gravitational field due to the circulating flow of electromagnetic radiation of a unidirectional ring laser is found by solving the linearized Einstein field equations at any interior point of the laser ring. The general relativistic spin equations are then used to study the behavior of a massive spinning neutral particle at the center of the ring laser. It is found that the particle exhibits the phenomenon known as inertial frame-dragging. q2000 Elsevier Science B.V. All rights reserved.

http://temporology.bio.msu.ru/EREPORTS/mallett.pdf

Sol

- Feb 4, 2004 7:33 pm (#3 of 38)

What Time Is It There?

The century-old dream of time travel remains one of our greatest control fantasies—irrational and irresistible, supremely conducive to megalomania, born of morbid curiosity and mortal dread. Barring the odd literary anachronism (Rip Van Winkle's big-sleep displacement, the Connecticut Yankee's Camelot stopover), it wasn't until 1895, when H.G. Wells unveiled The Time Machine, that the concept crystallized in the public consciousness, spanning nuts-and-bolts mechanics to abstruse metaphysics.

http://www.villagevoice.com/issues/0216/edlim.php

Sol

- Feb 4, 2004 7:46 pm (#4 of 38)

A Primer onTime Travel

But the easiest and most plausible time machine that can be constructed is what's known as a Tipler Cylinder. The materials may be practically "exotic" and the energy requirements enormous, but according to Dr. Frank Tipler of Tulane University in 1974, the construction of a time machine is theoretically feasible. He determined that if you somehow rotate an infinitely long massive cylinder fast enough, it would also "tip" a series of light cones into a CTC. (See B) The speed at the outer surface of the cylinder, though, would have to be greater than half the speed of light. But if something were to rotate this fast, part of it would likely collapse into a singularity - an infinitely small point of space-time, usually caused by a star collapsing under its own gravity, that has infinite mass and where the laws of physics break down. And Tipler stresses, "The stability of massive rotational bodies is questionable. The energy associated with a strong angular momentum would have to be about equal to the rest-mass energy, energy so great that the accompanying centrifugal force may tear the rotating body apart."

http://www.readmag.com/Columns/timetravel.htm

Sol

- Feb 4, 2004 7:51 pm (#5 of 38)

Time Travel in Einstein's Universe: The Physical Possibilities of Travel through Time

The notion of closed timelike curves in the real world is hard to reconcile with our intuitive understanding of causality. Perhaps one can find global solutions to general relativity incorporating closed timelike curves. These, in effect, would be time machines. But it may be impossible to construct such a system in a local region of space. Theorems along these lines were proved by Frank Tipler in the 1970s. Tipler assumed that the energy density was never negative and showed that closed timelike curves could never arise in a local region without also creating a singularity. This was reassuring, as we could hope that both the singularity and the closed timelike curves were hidden behind an event horizon (although this was not part of the proof).

http://pancake.uchicago.edu/~carroll/gottreview.html

Sol

- Feb 4, 2004 7:57 pm (#6 of 38)

How to Build a Time Machne

by Paul Davies

In science fiction, wormholes are sometimes called stargates; they offer a shortcut between two widely separated points in space. Jump through a hypothetical wormhole, and you might come out moments later on the other side of the galaxy. Wormholes naturally fit into the general theory of relativity, whereby gravity warps not only time but also space. The theory allows the analogue of alternative road and tunnel routes connecting two points in space. Mathematicians refer to such a space as multiply connected. Just as a tunnel passing under a hill can be shorter than the surface street, a wormhole may be shorter than the usual route through ordinary space.

http://www.sciam.com/article.cfm?articleID=0004226A-F77D-1D4A-90FB809EC5880000&pageNumber=2&catID=2

Sol

- Feb 4, 2004 8:01 pm (#7 of 38)

In the beginning - It's hard to grasp, but the Universe may have made itself

Gott and Li found that a time loop could have existed before the big bang without violating any laws of physics. Space would have been in a loop of time, perpetually re-creating itself. If so, the Universe could be viewed as having given birth to itself. Gott says that asking what the first event in the Universe was becomes meaningless. "Every event in the Universe could have an event preceding it," he says.

One consequence of the idea is a natural explanation for the so-called arrow of time. Theories of general relativity and electromagnetism do not rule out the idea that waves can affect events that occurred in the past. For instance, they do not forbid light from travelling back in time.

Yet in our Universe light always travels with us into the future. The reason, say Gott and Li, has to do with what would happen to waves that regressed in time in the kind of universe they envisage. "They would travel back to the epoch of the time loop and circle forever, constantly reinforcing each other," says Gott. Such a universe could not exist, Gott concludes, because the time loop would quickly become unstable.

http://cfa-www.harvard.edu/~lli/personal/html/beginning.html

Sol

- Feb 4, 2004 8:06 pm (#8 of 38)

Will We Travel Back (Or Forward) in Time? by RICHARD GOTT III

Einstein proved we can travel forward by moving near light speed. Backward requires a wormhole, cosmic string and a lot of luck

Do the laws of physics permit time travel, even in principle? They may in the subatomic world. A positron (the antiparticle associated with the electron) can be considered to be an electron going backward in time. Thus, if we create an electron-positron pair and the positron later annihilates in a collision with another, different electron, we could view this as a single electron executing a zigzag, N-shaped path through time: forward in time as an electron, then backward in time as a positron, then forward in time again as an electron.

http://www.time.com/time/reports/v21/science/time.html

Sol

- Feb 4, 2004 8:11 pm (#9 of 38)

A User's Guide to Time Travel, By Michio Kaku

Not anymore. Having examined Einstein's equations more closely, physicists now realize that the river of time may be diverted into a whirlpool - called a closed timelike curve - or even a fork leading to a parallel universe. In particular, the more mass you can concentrate at a single point, the more you can bend the flow.

http://www.wired.com/wired/archive/11.08/pwr_timetravel_pr.html

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