Once Before Time - Martin Bojowald [117]
Energy companies had at first supported wide-scale horizon broadening, too, but for another reason: They had realized the danger of the continued expansion of the universe. The consequent dilution of matter would, very slowly but unavoidably, not allow even heavy black holes, the last sources of energy, to exist for long. They lobbied for the Buchert decelerator: Dark energy as the source of accelerated expansion had long been recognized as a consequence of inhomogeneity in a universe having become more structured after the big bang. In the belief that the inhomogeneity would weaken when numerous galaxies disappeared in black holes, horizon broadenings were initially undertaken without restriction.
This was doomed to be an immense failure, for matter fallen into black holes contributes to their mass and does not sufficiently weaken the gravitational force and its inhomogeneous distribution. Except for the expurgation of galaxies, excessive horizon broadenings had had hardly any consequences. Still, they did contribute somewhat to a weakened acceleration, which quite naturally occurred as a result of the dilution of inhomogeneity in an expanding universe. Of course, the intergalactic government celebrated this as a success of military- and energy-political adventures.
While such memories from the history books passed through his mind, the gravonomist concluded that his latest observation was a natural explosion after the evaporation of a black hole, and he almost returned to his reading. But this signal was slightly different: When his glance once more glided over the screen, which showed the gravitational wave spectrum in all its details, he noticed something remarkable.
The evaporation and explosion of black holes had successfully been described by stoop theory, established after millennia-long efforts as the theory of quantum gravity. It combined the advantages of all its predecessor theories. Developed just in time, the theory had been tested on the last breaths of the ever more rapidly paling cosmic background radiation: it was a spectacular success. Later on, when the first black holes had exploded, these details too were very precisely described by stoop theory, which was ever since considered the final and fundamental theory of the universe. In the latest event the gravonomist easily recognized the characteristic features of the gravitational wave spectrum of an exploding black hole. But there was a weak, unaccounted-for high-frequency contribution rising just above the measurement uncertainties. Might stoop theory not be the last word of theoretical physics after all?
The news of possible deviations between theory and observations—the first after many centuries—spread like a brushfire. New calculations were undertaken and modifications of stoop theory postulated, which all turned out to be unsuccessful. Compared to this, the final explanation of the deviations initially looked more down-to-earth: It was a historian who in old records found references to the capsule Kruskal and its long-ago mission flown into the central black hole of an average galaxy. Details were no longer to be found, but now scientists easily managed to trace back the high-frequency part of the gravitational wave measurement to the capsule’s signal on its way into the center, to its own demise. And thus the new observation did, after all, contribute to a triumph of the theory, for the first clearly identifiable signal was seen that, unlike light, was able to penetrate the extremely hot and dense central region of a black hole. Once the origin of the signal was known, the observation could clearly be reconciled with theory …
7. THE ARROW OF TIME
AN AGING WORLD
We fought with the Megadae who are born old, and grow younger and younger every year, and die when they are little children …
—OSCAR WILDE, The Fisherman and His Soul
Time is often annoying. Everything would be so much easier if time would only behave like space. One could then simply take a step back in time to correct