In 1982 Ed Witten discovered one of the most astounding solutions to Einstein's equation: bubbles of nothing - topological holes in the fabric of space-time. More recently Samir Mathur and others drafted those bubbles of nothing to construct fuzzballs - black holes that solve the information paradox while preserving causality. When we had an impromptu discussion of this topic a couple of weeks ago I pointed out some potential issues with bubbles of nothing dynamics. Turns out these concerns result from unwarranted implicit assumptions. A more careful examination resolves those issues and clarifies the options for bubbles dynamics.
Time permitting I will also show that black holes can have lower entropy density than implied by Beckenstein's ground-breaking analysis.
The discussions will be informal, phenomenological, and based only on undergrad math at most.
Moshe Rozenblit PhD