The black hole information paradox
Throw a book into a black hole. Is its information gone forever — or would that break physics itself?
What makes this fascinating
Hawking's puzzle — Black holes slowly evaporate — but that seems to destroy information, which quantum mechanics forbids.
A clash of two pillars — General relativity says the information is lost; quantum theory says it can't be. Both can't be right.
Recent progress — New “island” calculations suggest information does escape — but the full mechanism is still unsettled.
Frequently asked questions
- What is the black hole information paradox?
- Quantum mechanics says information cannot be destroyed, but Stephen Hawking showed black holes radiate and eventually evaporate — seemingly erasing the information of whatever fell in.
- Is the paradox resolved?
- Not definitively. Recent work on 'islands' and the Page curve suggests information does escape, but a complete, universally accepted resolution does not yet exist.
- Why does it matter?
- It sits exactly where general relativity and quantum mechanics collide, so resolving it is widely seen as a crucial clue toward a theory of quantum gravity.
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The nature of dark energy
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The quantum measurement problem
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