"Negative Energy and the Focussing of Light Rays," by Aron Wall (Institute for Advanced Study)

Thursday, February 25, 2016 - 10:00am to 11:00am
TEP Seminars

TEP Seminar

Physics & Astronomy Building (PAB) 4-330
Thursday, February 25, 2016

Guest Speaker: Aron Wall (Institute for Advanced Study)

Talk Title: "Negative Energy and the Focussing of Light Rays"


In any quantum field theory, the energy flux at a point of spacetime can be negative. This would produce a repulsive gravitational field causing nearby light rays to defocus. This in turn threatens to produce a variety of exotic phenomena including traversable wormholes, warp drives, time machines, and evasion of singularity theorems.  I will describe a new "quantum focussing conjecture" that prevents such pathologies. In the flat spacetime limit it reduces to a novel lower bound on the energy density, which can be proven for several classes of field theories.

Event Attachments: 
PAB 4-330