Although "wormhole" may be easier to remember, the name "Einstein-Rosen Bridge" is also used in physics.
Wormholes in Popular Fiction and Einstein's Relativity
Einstein-Rosen Bridges (ERBs), or wormholes, are a popular feature in science fiction. They were featured prominently in shows such as Star Trek: Voyager and Sliders. These portals have their basis in Einstein's Theory of General Relativity.
A wormhole exists at the center of a black hole. A black hole is a star which has collapsed; its massive gravitational field sucks in everything which passes the boundary, called the event horizon. For more information on black holes, see Isaac McPhee's 2008 Suite101 article, "What is a Black Hole?"
If a particle (or object) were to travel down into the "throat" or center of a black hole in space, it would enter a different area of both space and time. The process would kill any living being; Einstein postulated that gravity would increase to infinity at the center of the black hole, tearing apart even the atoms of whatever passed through.
White Holes
A white hole, the exit point to the ERB, is a black hole which runs backward in time. Black holes swallow whatever comes into contact with them, while white holes regurgitate them.
White holes should not be able to exist, because they would spontaneously create order out of disorder, effectively violating the Second Law of Thermodynamics.
Roy Kerr and the Spinning Black Hole
In 1963, mathematician Roy Kerr remedied a major difficulty of Einstein's theory by proving that, due to the principle of conservation of angular momentum, a star in the process of collapse would increase its rotation. It would have at its center a ring of neutrons manifesting extraordinary centrifugal force outward, countering the force of gravity on the inside.
A particle, object, or traveller would then not be crushed by the forces, but would travel through the point of singularity and exit the other side of the black hole, or white hole, perhaps within the same universe at a different location or time, or perhaps in a parallel universe.
However, any travel through this Kerr ring would be necessarily one-way. The gravity created by the collapse, though no longer sufficient to kill the individual, would prevent a return trip.
Complications with Travel through a Kerr Ring
Physicists calculating the logistics of this form of travel find that a traveler may not survive travel through this medium. A light beam which followed an individual would acquire so much energy in the length of the ERB that it would kill the person and create such a high gravitational field that it would close the bridge.
How to Keep an ERB Open
John Wheeler, in 1962, (who first used the term "wormhole") found that an ERB is unstable in space, and if it opened, it would close again instantly, before a photon could travel through it.
An ERB would need a supply of negative energy in order to stay open, through a process such as the Casimir effect, which generates negative energy. Unfortunately, the Casimir effect only generates very small amounts of negative energy.
Physicists speculate that if large amounts of negative energy could be discovered, perhaps by an advanced society, then the creation of an ERB may be possible.
Consulted Works on ERB
This article reviews information from theoretical physicist Michio Kaku's 2004 book Parallel Worlds, published by Anchor Press.
 |
