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No. 56: Mar-Apr 1988

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Do black holes exist?

Can we believe our eyes? Dare anyone suggest that black holes do not lurk out in the cosmos sucking in stars and unwary spaceships? It's all true; an arti cle bearing the above title appeared in the January 1988 number of Sky and Telescope. Doubts do surface once in a while, despite all the TV documentaries, all the textbooks, and all the newspaper jottings, where black holes are described in the hushed tones used only with profound truths of nature.

To set the stage, we quote a paragraph from said article:

"There is, however, a serious problem with black holes, one that leaves some scientists skeptical about their existence. The overarching mystery lies hidden at a hole's center. Einstein's general theory of relativity predicts that we will find there an object more massive than a million Earths and yet smaller than an atom -- so small, in fact, that its density approches infinity. The idea of any physical quantity becoming infinite flies in the face of everything we know about how nature behaves. So there is good reason to be skeptical that such a nasty thing could happen anywhere at all."

Among the observations that hint at the reality of black holes are the X-ray binaries. In a typical X-ray binary, prodigious, flickering fluxes of X-rays reveal the presence of an ultradense star and an orbiting companion. The rapid orbital motion of the companion star tells us that the central X-ray star has a mass of more than three suns. General Relativity assures us that such a star can only collapse further to form a black hole. Therefore, black holes must exist.

J. McClintock, the author of this article, does not buy this reasoning. General Relativity, he says, has been shown to be valid so far only in weak gravitational fields, not in the very powerful gravitational fields of an X-ray star. "...we presume that Einstein's theory correctly describes strong gravity when we argue that certain X-ray stars are black holes, yet, at the same time, these alleged black holes are the acid test of Einstein's theory of strong gravity." (McClintock, Jeffrey; "Do Black Holes Exist?" Sky and Telescope, 75:30, 1988.)

Comment. The long history of science teaches us that all theories are eventually displaced by more accurate, more all-inclusive formulations. Unfortunately, this makes textbook writing difficult.

From Science Frontiers #56, MAR-APR 1988. 1988-2000 William R. Corliss

Science Frontiers Sourcebook Project Reviewed in:

Quotes

  • "A sourcebook of unexplained phenomena is therefore a valuable addition to a collection of scientific literature. William R. Corliss has provided this in the past with his source books of scientific anomalies in several subjects, and now he has provided it for astronomy. He has done an excellent job of collecting and editing a large amount of material, taken in part from scientific journals and in part from scientific reporting in the popular or semi-scientific press." -- "The Mysterious Universe: A Handbook of Astronomical Anomalies", reviwed by Thomas Gold, Cornell University, in Icarus, vol.41, 1980

  • "An interesting, systematic presentation of unusual weather [..] This book is recommended for a general audience" --"Corliss, William R., Tornados, Dark Days, Anomalous Precipitation, and Related Weather Phenomena, Sourcebook Project, 1983.", revieweed in Choice, September 1983
  • "..the science is necessarily somewhat speculative, but Corliss's symthesis is based on reputable sources." -- "Corliss, William R. (Compiler). Lightning, Auroras, Nocturnal Lights, and Related Luminous Phenomena" reviwed by Joseph M. Moran, Univ. of Wisconsin in Science Books and Films, Sep/Oct 1983

  • "Before opening the book, I set certain standards that a volume which treads into dangerous grounds grounds like this must meet. The author scrupulously met, or even exceeded those standards. Each phenomenon is exhaustively documented, with references to scientific journals [..] and extensive quotations" -- "Book Review: The moon and planets: a catalog of astronomical anomalies", The Sourcebook Project, 1985., Corliss, W. R., Journal of the Royal Astronomical Society of Canada, Vol. 81, no. 1 (1987), p. 24., 02/1987