Stephen Hawking made a number of memorable contributions to physics, but perhaps his greatest was a puzzle: what happens to information that falls into a black hole? The question sits squarely at the overlap of quantum mechanics and gravitation, an area in which direct experimental input is hard to come by, so a great number of leading theoretical physicists have been thinking about it for decades. Now there is a possibility that physicists might have made some progress, by showing how subtle effects relate the radiation leaving a black hole to what’s going on inside. Netta Engelhardt is one of the contributors to these recent advances, and together we go through the black hole information puzzle: what it is, what we have learned about it, and what it all might teach us about quantum gravity.

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