Showing papers by "Roger Penrose published in 1971"
TL;DR: In this article, the authors consider the extraction of rotational energy from a black hole, not least because the rotational energies should be comparable with the total mass energy of the black hole.
Abstract: THERE has been considerable interest recently in the question of the gravitational collapse of a massive body and of the possible astrophysical consequences of the existence of the “black hole” which general relativity predicts should sometimes be the result of such a collapse. In particular, the question has arisen whether the mass-energy content of a black hole could, under suitable circumstances, be a source of available energy. We now consider the extraction of rotational energy from a black hole, not least because the rotational energy (defined appropriately) of a black hole should, in general, be comparable with its total mass-energy1.
431 citations
TL;DR: Werner10 has presented a plausible case for believing that his detectors may indeed have monitored frequent and sharply pulsed gravitational waves, which seem to be emanating from the centre of the authors' galaxy.
Abstract: IT has long been recognized that Einstein's gravitational equations admit wave-like solutions. But because of the smallness of the gravitational constant it would require an exceedingly violent astronomical process to generate gravitational waves of sufficient intensity to be detectable with available apparatus. Weber10 has, however, presented a plausible case for believing that his detectors may indeed have monitored frequent and sharply pulsed gravitational waves, which seem to be emanating from the centre of our galaxy. Because such waves could give some very significant information about extraordinary processes which may be taking place in certain regions of the universe, the detection of gravitational waves may be important in the observational astronomy of the future.
294 citations