Bubbles of nothing in the Kaluza-Klein Vacuum (link)
A review of Witten's classic construction of the bubble of nothing spacetime, a discussion of instantons, a rumination on higher dimensional generalizations.
Can the Standard Model arise from Kaluza-Klein compactification alone? (link)
Obtaining gauge symmetry from diffeomorphism invariance, analysis on homogenous spaces, index theorems for Dirac operators on compact spaces.
Path integrals for the symmetric double well (link)
Generalities with the path integral, evaluation of fluctuation determinants, interacting fluctuation expansions, degeneracy splitting by instantons in the dilute gas approximation.
Unitarity theorems for black hole evolution (link)
Page's theorem 'proven' two ways, measures and metrics on the space of mixed quantum states, the Hayden-Preskill thought experiment, comments on black hole complementarity and matrix ensembles.