Could We Find a Door To A Parallel Universe?

p1234 writes "Though no direct evidence for wormholes has been observed, this could be because they are disguised as black holes. Now Alexander Shatskiy of the Lebedev Physical Institute in Moscow, Russia, is suggesting a possible way to tell the two kinds of object apart. His idea assumes the existence of a bizarre substance called "phantom matter", which has been proposed to explain how wormholes might stay open. Phantom matter has negative energy and negative mass, so it creates a repulsive effect that prevents the wormhole closing. 'US expert Dr Lawrence Krauss, from Case Western Reserve University in Cleveland, Ohio, points out that the idea rests on untested assumptions. He told New Scientist magazine: "It is an interesting attempt to actually think of what a real signature for a wormhole would be, but it is more hypothetical than observational. Without any idea of what phantom matter is and its possible interactions with light, it is not clear one can provide a general argument."'"

Comments

We published this already

[Geoffrey.landis]

This is interesting, but looking at the article, i can't see that it's much different from work that we published over a decade back in a paper where we pointed out properties of wormholes, and noted that they might be visible by the signature of the negative effective mass on the bending of light: Natural Wormholes as Gravitational Lenses, John G. Cramer, Robert L. Forward, Michael S. Morris, Matt Visser, Gregory Benford, Geoffrey A. Landis. U.C. Irvine even wrote a press release about this paper, which I've put on my website.

It's a little hard to tell from this very brief article, but what he calls "phantom matter" is what other physicists call "exotic matter" or sometimes "negative matter," which violates one of the positive energy-conditions, and thus has negative energy (in some reference frame). Matt Visser's book Lorentzian Wormholes has a lot more technical details about the various formulations of the positive-energy conditions.