Do Black Holes Delete Reality?

"Around 38 percent of websites that were on the Internet in 2013 are gone now. Half of Wikipedia pages reference dead links. Information seems to be disappearing all around us, and that's nothing new. Over geological time, information loss is the norm, not the exception. Yet according to physics, information is never destroyed. In principle, a burned book is just as readable as the originalif you analyze the ashes of the fire, the smoke and the flames to re-create the incinerated words."

"If you know everything about the cosmos in the present, then you should be able to rewind it and understand everything about it in the past and predict everything about it in the future. In other words, knowledge is always preserved; destroying information is impossible, according to the fundamental laws of physics. Or is it? In some special parts of the universe, such as inside black holes, information seems to get lost."

Approximately 38 percent of websites present in 2013 have disappeared, and half of Wikipedia pages cite dead links, illustrating pervasive information loss in practice. Over geological timescales, information loss is common, yet quantum mechanics' unitarity principle implies reversible evolution and preservation of information. In principle, destroyed records could be reconstructed from physical remnants. Black holes, however, present an apparent contradiction by seeming to eradicate information, creating a long-standing paradox. Recent theoretical advances suggest mechanisms by which information can escape black holes, but resolving the issue requires understanding how gravity behaves at the quantum level. Investigating information's fate may guide development of quantum gravity.

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