Negative Energy and the Focussing of Light Rays

Date and Time


MacN 222



Aron Wall


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.


Coffee and Refreshments will be available prior to the colloquium in MacN 218.

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