Category:Black hole

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The term black hole was popularised by John Wheeler in the 1960s to refer to bodies under GR1960 that had a radius equal or less than the critical radius r=2M, and therefore could not radiate directly.

Black holes vs dark stars

A black hole is qualitatively different to a Newtonian dark star, even though they have the same critical horizon radius – a dark star is still capable of indirect radiation, and can therefore still transmit information, lose massenergy, and shrink, whereas the horizon of a GR1960 black hole is completely, totally black, with a temperature of absolute zero. Coupled with the absence of emitted radiation - a black hole presents a view to the outside universe that, apart from the "fossil" signals of infallen objects that are frozen into the event horizon region, is essentially a void – makes the term "black hole" appropriate.

Black holes under QM aren't black, or holes

According to quantum mechanics, black holes must radiate and leak information - the defining features of a GR1960 black hole are not present in the QM description – this means that technically,a QM black hole is not actually a black hole in the original sense, and that if QM is correct, Wheeler-style black holes do not actually exist in reality as originally described - the QM description seems more reminiscent of a statistical description of indirect radiation from a dark star.

However, the name "black hole" is now so popular that it is popularly used as the default name for almost any object bounded by an event horizon, regardless of what they horizon physics might actually be.

Subcategories

This category has only the following subcategory.

Pages in category "Black hole"

The following 2 pages are in this category, out of 2 total.