The Black Hole Wars

I was part of a “podcast with video” series on the “Black Hole Wars” that the students at DAMTP organized as part of the 2021 Cambridge Festival. This was the concluding episode in a series exploring the information paradox.

I tried to explain how theories of gravity store quantum information differently from other quantum field theories; how this is an effect that was missed in Hawking’s argument for information loss; and how replacing Hawking’s “principle of ignorance” (about the interior) with a “principle of holography of information” provides a neat resolution to the paradox.

The festival is a public outreach program at the University, and so I was told not to target Cambridge undergraduates and to keep things at a high school level i.e. not even assume the Gauss law or the uncertainty principle! I’m not sure I succeeded at that but hopefully some of it is accessible to undergraduate students.

I’ve also never tried to explain a complex scientific topic in a “podcast style” conversation. This has its own challenges. In a popular talk, one can start at a basic level and then organize topics in some clever way to communicate an advanced idea or at least build up a sequence of analogies. But here the idea was to bring out the physics as part of a conversation.

Anyway, it was a new experience, so I had fun.

Thanks to Ayngaran Thavanesan for organizing this and to Rifath Khan and Goncalo Regado for anchoring the conversation.