In the 1930s, the theoretical physicist J. Robert Oppenheimer and one of his graduate students at the University of California, Hartland Snyder, proposed what seemed like a wildly improbable idea. When the nuclear fires of extremely massive stars die out, they suggested, the stars collapse so completely under the pull of their own gravity that they literally crush themselves out of existence, leaving only a "black hole" in space as evidence of their passing. Now, just as scientists are beginning to study the first tentative signs that there really may be such black holes (TIME, April 5), they are also being asked to consider another fantastic notion: the existence of "white holes."
In Nature, Astrophysicist Robert M. Hjellming of the National Radio Astronomy Observatory at Green Bank, W. Va., argues the possibility of holes that are the complete antithesis of black holes. Such opposites are common enough—for example, the negatively charged electron and its antimatter version, the positively charged positron. But Hjellming's white holes are more than simply mirror images of black holes. They are sources of matter that could literally come from out of this world.
Popping Matter. Hjellming's hypothesis may be the answer to a question that has bothered scientists ever since the existence of black holes was proposed: If matter really vanishes inside black holes, as if they were bottomless pits, where has the matter gone? British Theorist Roger Penrose suggested some time ago that the missing matter may pop out elsewhere in the universe —or even in an entirely different universe.
Picking up where Penrose left off, Hjellming says that the point at which the matter re-emerges in the other universe would be a white hole. Even more intriguing, this passage of matter would not be a one-way street. Matter would also leave the other universe through black holes, says Hjellming, and appear in ours through white holes. Thus the flow of matter between the two universes would be kept in balance.
Hjellming admits that such strange funnels between universes sound about as real as the rabbit hole through which Alice tumbled into Wonderland. But, he adds, some evidence may already be at hand that white holes do exist. One of the great puzzles of contemporary astrophysics is the huge amount of energy —cosmic rays, X rays, infrared radiation —that is apparently coming from distant quasars and from the centers of galaxies, including the earth's own Milky Way; the output seems to be greater than can be accounted for by known physical processes, including the conversion of matter into energy by thermonuclear explosions. If it could be shown that matter and energy were coming from another universe, Hjellming says, that problem would be neatly solved.
Source: Time
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