Saturday, February 11, 2012

WORMHOLE

wormhole


wormhole
A hypothetical "tunnel" connecting two different points in spacetime in such a way that a trip through the wormhole could take much less time than a journey between the same starting and ending points in normal space. The ends of a wormhole could, in theory, be intra-universe (i.e. both exist in the same universe) or inter-universe (exist in different universes, and thus serve as a connecting passage between the two). 

Wormholes arise as solutions to the equations of Einstein's general theory of relativity. In fact, they crop up so readily in this context that some theorists are encouraged to think that real counterparts may eventually be found or fabricated and, perhaps, used for high-speed space travel and/or time travel. However, a known property of wormholes is that they are highly unstable and would probably collapse instantly if even the tiniest amount of matter, such as a single photon, attempted to pass through them. A possible way around this problem is the use of exotic matter to prevent the wormhole from pinching off. 


A brief history of wormholes

The theory of wormholes goes back to 1916, shortly after Einstein published his general theory, when Ludwig Flamm, an obscure Austrian physicist, looked at the simplest possible solution of Einstein's field equations, known as the Schwarzschild solution (or Schwarzschild metric). This describes the gravitational field around a spherically-symmetric non-rotating mass. If the mass is sufficiently compact, the solution describes a particular form of the phenomenon now called a black hole – the Schwarzschild black hole. Flamm realized that Einstein's equations allowed a second solution, now known as a white hole, and that the two solutions, describing two different regions of (flat) spacetime were connected (mathematically) by a spacetime conduit.1 Because the theory has nothing to say about where these regions of spacetime might be in the real world, the black hole "entrance" and white hole "exit" could be in different parts of the same universe or in entirely different universes. 

In 1935, Einstein and Nathan Rosen further explored, it can be appreciated with hindsight, the theory of intra- or inter-universe connections in a paper2 whose actual purpose was to try to explain fundamental particles, such as electrons, in terms of spacetime tunnels threaded by electric lines of force. Their work gave rise to the formal name Einstein-Rosen bridge for what the physicist John Wheeler would later call a "wormhole." (Wheeler also coined the terms "black hole" and "quantum foam".) Wheeler's 1955 paper3 discusses wormholes in terms of topological entities called geons and, incidentally, provides the first (now familiar) diagram of a wormhole as a tunnel connecting two openings in different regions of spacetime. 


Traversable wormholes

wormhole diagram
Interest in so-called traversable wormholes gathered pace following the publication of a 1987 paper by Michael Morris, Kip Thorne, and Uri Yertsever (MTY) at the California Institute of Technology.4, 5 This paper stemmed from an inquiry to Thorne by Carl Sagan who was mulling over a way of conveying the heroine in his novel Contact across interstellar distances at trans-light speed. Thorne gave the problem to his Ph.D. students, Michael Morris and Uri Yertsever, who realized that such a journey might be possible if a wormhole could be held open long enough for a spacecraft (or any other object) to pass through. MTY concluded that to keep a wormhole open would require matter with a negative energy density and a large negative pressure – larger in magnitude than the energy density. Such hypothetical matter is called exotic matter.

Although the existence of exotic matter is speculative, a way is known of producing negative energy density: theCasimir effect. As a source for their wormhole, MTY turned to the quantum vacuum. "Empty space" at the smallest scale, it turns out, is not empty at all but seething with violent fluctuations in the very geometry of spacetime. At this level of nature, ultra-small wormholes are believed to continuously wink into and out of existence. MTY suggested that a sufficiently advanced civilization could expand one of these tiny wormholes to macroscopic size by adding energy. Then the wormhole could be stabilized using the Casimir effect by placing two charged superconducting spheres in the wormhole mouths. Finally, the mouths could be transported to widely-separated regions of space to provide a means of FTL communication and travel. For example, a mouth placed aboard a spaceship might be carried to some location many light-years away. Because this initial trip would be through normal spacetime, it would have to take place at sublight speeds. But during the trip and afterwards instantaneous communication and transport through the wormhole would be possible. The ship could even be supplied with fuel and provisions through the mouth it was carrying. Also, thanks to relativistic time-dilation, the journey need not take long, even as measured by Earth-based observers. For example, if a fast starship carrying a wormhole mouth were to travel to Vega, 25 light-years away, at 99.995% of the speed of light (giving a time-dilation factor of 100), shipboard clocks would measure the journey as taking just three months. But the wormhole stretching from the ship to Earth directly links the space and time between both mouths – the one on the ship and the one left behind on (or near) Earth. Therefore, as measured by Earthbound clocks too, the trip would have taken only three months – three months to establish a more-or-less instantaneous transport and communications link between here and Vega. 

Star Trek wormhole
Star Trek's Deep Space 9 is located alongside a natural wormhole that leads to the other side of the Galaxy
Of course, the MTY scheme is not without technical difficulties, one of which is that the incredibly powerful forces needed to hold the wormhole mouths open might tear apart anything or anyone that tried to pass through. In an effort to design a more benign environment for travelers using a wormhole, Matt Visser of Washington University in St. Louis conceived an arrangement in which the spacetime region of a wormhole mouth is flat (and thus force-free) but framed by struts of exotic matter that contain a region of very sharp curvature.6 Visser envisages a cubic design, with flat-space wormhole connections on the square sides and cosmic strings as the edges. Each cube-face may connect to the face of another wormhole-mouth cube, or the six cube faces may connect to six different cube faces in six separated locations. 

In 2011, Panagiota Kanti (University of Ioannina) and Burkhard Kleihaus (Universität Oldenburg) showed how it might be possible to construct traversable wormholes without using exotic matter by resorting to a form of string theory.10 

Given that our technology is not yet up to the task of building a wormhole subway, the question arises of whether they might already exist. One possibility is that advanced races elsewhere in the Galaxy or beyond have already set up a network of wormholes that we could learn to use. Another is that wormholes might occur naturally. David Hochberg and Thomas Kephart of Vandebilt University have discovered that, in the earliest moments of the Universe, gravity itself may have given rise to regions of negative energy in which natural, self-stabilizing wormholes may have formed. Such wormholes, created in the Big Bang, might be around today, spanning small or vast distances in space. 
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GENESIS 14

Mountains_spitzer_f800

ZAANUSSII

18

SOL PRIMUS

The Sun Gif

RIGELAN DEFENCE FORCE


BARUUL MERC

THE TWINS

http://a52.g.akamaitech.net/f/52/827/1d/www.space.com/images/h_et_planets_02.jpg

AZRIL

MATRIX 33

KELEV

STEINMAN CLASS B HEAVY HAULER

Steinman Class B Heavy Hauler

While it will never get the glory of a Crossbow, or even the quiet respect of a Starmaster, the Steinman is, arguably, the most important starship in human space. The vessel, over 70 years old, is quite simply the lynchpin in all interstellar human commerce, without which there could be no Protectorate.

Little more than a command module, a pair of engines and a cargo hold, the Steinman is a simple, but effective design that has kept colonies, core worlds, and the military supplied through peace, war, and across a hundred varying climates.

Not at all fast, and usually completely unarmed, the ship’s only defense is a powerful passive sensor system, and a negative mass drive with the shortest warm-up time of any non-military human ship in operation. Often traveling in convoys with a few escort vessels, a pack of Steinman under attack will quickly go to FTL using preset coordinates, so that there is a much shorter navigational computation time. An average ship takes 1D4 minutes to perform a jump, but a Steinman can usually do it in half that (most military ships have the same jump time).

With a crew of six, a modular cargo hold that can haul up to 500 tons, and a very reasonable price tag, it is the ship of choice for most large corporations, and is the transport of choice for the military as well. But even the military versions rarely have armaments. To keep space consumption to a minimum, the Steinman has a very small power plant. At most, it might be able to be fitted with a turret, but not a very powerful one. A much more reasonable option for arming the Steinman is to put missiles on it, which need no large power source.

Steinman haulers are most often encountered hauling food, raw materials, dry goods, water, large groups of people and military supplies. Pirates tend to avoid them because highly valuable cargo is much more likely to be on a smaller, better armed, light or medium transport. Some budget colony operations also use them to transport colonization supplies and colonists. By dividing the massive cargo bay into two decks filled with bunk beds, the Steinman can carry up to 600 passengers.

Model: C-98 Class B Heavy Hauler

Class: Freighter

Crew: 6, capable of carrying up to 600 passengers

M.D.C. by location

Sensor array – 150

Engine pods (2) – 400 each

*Main body – 2,000

Command module – 800

*Depleting the M.D.C. of the main body would disable the vessel, causing the command module to detach as a life pod. Steinmans rarely explode; usually only when they are carrying highly flammable or volatile cargo.

Speed

Maximum Sublight Speed: .2 C, or 20% of the speed of light

Maximum Acceleration/Deceleration Rate: 4 Gs per melee round

Maximum FTL: 365 x C, or one light year per day, half that speed for civilian models.

Top Atmospheric Manuevering Speed: Mach 1.5, but can attain escape velocity on a full engine burn (cannot maneuver)

Statistical Data

Height: 44 ft

Length: 210 ft

Width: 115 ft

Cargo: 500 tons

Power Plant: Fusion Reactor

FTL Drive: NMD-365 (military) or NMD-183 (Civilian)

Range: varies with supplies carried. Estimated it could travel 400 light years, but none has ever tried.

Market Cost: 2 million credits new, 1 million credits used.

Weapon Systems: None

Sensors: The Steinman has a powerful early-warning system that gives it mass and electromagnetic field sensors with a range of 1 million miles, and powerful short-range sensors with a 300,000-mile range.

Followers