The ultimate function of the city is to enable connections
between people. Cities fail either because segregation means that
those connections fail to occur or because those connections create
calamities, such as epidemic outbreaks. New data sources...
I will talk about three interesting ingredients that goes into
the results on H\"{o}rmander type operators I presented at
Princeton (joint with Shaoming Guo and Hong Wang). They are all
related to algebraic or geometric properties of multivariate...
The ruled hypersurfaces are distinguished by being comprised of
lines. When this characteristic exists as a consequence of
vanishing principal curvatures, it yields possibilities for
comparison with cylinders extending over lower-dimensional...
In double-scaled SYK, the chord diagrams of Berkooz et al. give
rise to a bulk algebra and geometry. The algebra is a "quantum
deformation" of the JT gravitational algebra that includes a
deformation of SL(2,R). The growth of operator size (in...
Spacetime wormholes can lead to surprises in black hole physics.
We show that a very old black hole can tunnel to a white
hole/firewall by emitting a large baby universe. We study the
process for a perturbed thermofield double black hole in
Jackiw...
One puzzling aspect of holography is that it conjectures a
duality between a physical theory with a single rigid causal
structure (the non-gravitational "boundary theory") and one whose
causal structure is state-dependent (the gravitational "bulk...
Cauchy slice holography gives a duality between the wavefunction
on a Cauchy slice and the partition function of a T2 deformed
field theory. I will review this correspondence and discuss
its implications for the black hole information puzzle.
The...
