Scrambling Time and Causal Structure of the Photon Sphere of a Schwarzschild Black Hole

Understand

Recently, physicists have started applying quantum information theory to black holes.

• This led to the conjecture that black holes are the fastest scramblers of information, and that they scramble it in time order M log M, where M is the mass of the black hole in natural units.
• As stated above, the conjecture is not completely defined, as there are several possible definitions of scrambling times.
• It appears that not all papers that refer to this conjecture interpret it the same way.