这种说法与量子力学的相关理论出现相互矛盾之处。因为现代量子物理学认定这种物质信息是永远不会完全消失的。30多年来，汇祥跑步机 dp 138。一旦这个黑洞浓缩并蒸发消失后，该理论提到的黑洞辐射中并不包括黑洞内部物质的任何信息，还不断在以能量的形式向外界发出辐射。这就是著名的“霍金辐射”理论。汇康跑步机。但是，黑洞在形成过程中其质量减少的同时，霍金称自己通过计算得出结论，事实上被吸入黑洞深处的物质的某些信息可能会在某个时候释放出来。看着霍金。
“经典黑洞理论认为，它的运动就像人在跑步机上奔跑一样，自我。光线其实是可以穿越视界的。当光线逃离黑洞核心时，汇康跑步机。自己最初有关视界的认识是有缺陷的，否定。又会被重新释放到宇宙中。他在论文中承认，物质和能量在被黑洞困住一段时间以后，事实上不存在。而黑洞内的任何物质和辐射均不能穿出视界。听听汇祥跑步机 dp 138。
在这篇名为《黑洞的信息保存与气象预报》（Information Preservation and WeatherForecasting For BlackHoles）的论文中，黑洞其实是不存在的，英国著名科学家斯蒂芬•霍金教授再次以其与黑洞有关的理论震惊物理学界。他在日前发表的一篇论文中承认，
Raphael Bousso, a theoretical physicist at the University ofCalifornia, Berkeley, and a former student of Hawking’s, says thatthis latest contribution highlights how “abhorrent” physicists findthe potential existence of firewalls. However, he is also cautiousabout Hawking’s solution. “The idea that there are no points fromwhich you cannot escape a black hole is in some ways an even moreradical and problematic suggestion than the existence offirewalls,” he says. “But the fact that we’re still discussing suchquestions 40 years after Hawking’s first papers on black holes andinformation is testament to their enormous significance.”
Polchinski, however, is sceptical that black holes without anevent horizon could exist in nature. The kind of violentfluctuations needed to erase it are too rare in the Universe, hesays. “In Einstein’s gravity, the black-hole horizon is not sodifferent from any other part of space,” says Polchinski. “We neversee space-time fluctuate in our own neighbourhood: it is just toorare on large scales.”
“It would be worse than trying to reconstruct a book that youburned from its ashes,” says Page. In his paper, Hawking comparesit to trying to forecast the weather ahead of time: in theory it ispossible, but in practice it is too difficult to do with muchaccuracy.
If Hawking is correct, there could even be no singularity at thecore of the black hole. Instead, matter would be only temporarilyheld behind the apparent horizon, which would gradually move inwardowing to the pull of the black hole, but would never quite crunchdown to the centre. Information about this matter would notdestroyed, but would be highly scrambled so that, as it is releasedthrough Hawking radiation, it would be in a vastly different form,making it almost impossible to work out what the swallowed objectsonce were.
Unlike the event horizon, the apparent horizon can eventuallydissolve. Page notes that Hawking is opening the door to a scenarioso extreme “that anything in principle can get out of a blackhole”. Although Hawking does not specify in his paper exactly howan apparent horizon would disappear, Page speculates that when ithas shrunk to a certain size, at which the effects of bothquantummechanics and gravity combine, itis plausible that it could vanish. At that point, whatever was oncetrapped within the black hole would be released (although not ingood shape).
Although Page accepts Hawking’s proposal that a black hole couldexist without an event horizon, he questions whether that alone isenough to get past the firewallparadox. Thepresence of even an ephemeral apparent horizon, he cautions, couldwell cause the same problems as does an event horizon.
“The picture Hawking gives sounds reasonable,” says Don Page, aphysicist and expert on black holes at the University of Alberta inEdmonton, Canada, who collaborated with Hawking in the 1970s. “Youcould say that it is radical to propose there’s no event horizon.But these are highlyquantumconditions, and there’s ambiguityabout what space-time even is, let alone whether there is adefinite region that can be marked as an event horizon.”
Conversely, in the 1970s, Hawking also showed that black holescan slowly shrink, spewing out ‘Hawking radiation’. In that case,the event horizon would, in theory, become smaller than theapparent horizon. Hawking’s new suggestion is that the apparenthorizon is the real boundary. “The absence of event horizons meansthat there are no black holes — in the sense of regimes from whichlight can’t escape to infinity,” Hawking writes.
In place of the event horizon, Hawking invokes an “apparenthorizon”, a surface along which light rays attempting to rush awayfrom the black hole’s core will be suspended. In generalrelativity, for an unchanging black hole, these two horizons areidentical, because light trying to escape from inside a black holecan reach only as far as the event horizon and will be held there,as though stuck on a treadmill. However, the two horizons can, inprinciple, be distinguished. If more matter gets swallowed by theblack hole, its event horizon will swell and grow larger than theapparent horizon.
Now Hawking proposes athird, tantalizingly simple, option.Quantummechanics and general relativity remain intact, but black holessimply do not have an event horizon to catch fire. The key to hisclaim is thatquantumeffects around the black holecause space-time to fluctuate too wildly for a sharp boundarysurface to exist.
Beyond the horizon
This was alarming because, although the firewall obeyedquantumrules, it flouted Einstein’sgeneral theory of relativity. According to that theory, someone infree fall should perceive the laws of physics as being identicaleverywhere in the Universe — whether they are falling into a blackhole or floating in empty intergalactic space. As far as Einsteinis concerned, the event horizon should be an unremarkableplace.
But on analysing the situation in detail, Polchinski’s team cameto the startling realization that the laws ofquantummechanics, which govern particles on small scales, change thesituation completely.Quantumtheory, they said, dictates thatthe event horizon must actually be transformed into a highlyenergeticregion, or ‘firewall’, thatwould burn the astronaut to a crisp.
In a thought experiment, the researchers asked what would happento an astronaut unlucky enough to fall into a black hole. Eventhorizons are mathematically simple consequences of Einstein’sgeneral theory of relativity that were first pointed out by theGerman astronomer Karl Schwarzschild in a letter he wrote toEinstein in late 1915, less than a month after the publication ofthe theory. In that picture, physicists had long assumed, theastronaut would happily pass through the event horizon, unaware ofhis or her impending doom, before gradually being pulled inwards —stretched out along the way, like spaghetti — and eventuallycrushed at the ‘singularity’, the black hole’s hypotheticalinfinitely dense core.
Hawking’s new work isan attempt to solve what is known as the black-hole firewallparadox, which has been vexing physicistsfor almost two years, after it was discovered by theoreticalphysicist Joseph Polchinski of the Kavli Institute and hiscolleagues (see ‘Astrophysics: Fire in the hole!’).
Hawking posted his paper on the arXiv preprint server on 22January1. He titled it, whimsically, ‘Information preservation andweather forecasting for black holes’, and it has yet to pass peerreview. The paper was based on a talk he gave via Skype at ameeting at the Kavli Institute for Theoretical Physics in SantaBarbara, California, in August 2013 (watch video of the talk).
“There is no escape from a black hole in classical theory,”Hawking told Nature.Quantumtheory, however, “enables energyand information to escape from a black hole”. A full explanation ofthe process, the physicist admits, would require a theory thatsuccessfully merges gravity with the other fundamental forces ofnature. But that is a goal that has eluded physicists for nearly acentury. “The correct treatment,” Hawking says, “remains amystery.”
In its stead, Hawking’s radical proposal is a much more benign“apparent horizon”, which only temporarily holds matter and energyprisoner before eventually releasing them, albeit in a more garbledform.
Notion of an ‘event horizon’, from which nothing can escape, isincompatiblewithquantumtheory,physicist claims.
Stephen Hawking: ‘There are no blackholes’