宇宙中有黑洞，还有白洞吗？（唠“科”）

Group 1 - The article discusses the theoretical concept of white holes, which are considered the opposite of black holes, expelling matter and energy instead of absorbing them [2][3]. - Black holes were once doubted in their existence until observational evidence, such as the detection of a black hole in the Cygnus X-1 system in 1971, confirmed their presence [2][3]. - The mathematical relationship between black holes and white holes suggests that they share the same properties, with the only difference being the direction of time [2][3]. Group 2 - There is currently no observational evidence supporting the existence of white holes, and some scientists argue that there is no reasonable mechanism for their formation [4]. - Some theories propose that white holes could explain certain cosmic phenomena, such as the energy output of quasars or even the origin of the universe, but these ideas lack observational support [4]. - A new hypothesis suggests that black holes could transform into white holes through a process of quantum rebound when matter is compressed to its limits, potentially allowing every black hole in the universe to become a white hole in the future [5].