jacky
问题补充说明：black hole
blackhole:
Anareaofspace-timewithaquantumsingularityatitscenter.Thesingularityhasatheoreticallyinfinitemass,makingitimpossibleforevenlighttoescape.AroundthesingularityisanEvent-Horizon.Thisisalsoknownasthepo训intofnoreturnbe来自causeitisthecriticalareathatlightcannolongerescapefrom,andtimeitselfcomestoanend,orisatthesametimead-infinitum.Muchworkhasbeendoneonthis360问答subjectbyStephenHawking.
