Quantum fields can sometimes have negative energy density. In gravitational contexts, this threatens to permit exotic phenomena such as traversable wormholes, warp drives, and time machines. I will discuss a new thermodynamics principle that can help to rule out such pathological situations. Despite the gravitational motivation, this principle has led us to an interesting lower bound on the energy, even for field theories in flat spacetime! This bound has since been shown to hold in several kinds of field theories.
Title
What prevents negative energy from violating causality?
Published
Berkeley, CA, University of California, Berkeley, Dept. of Physics, October 24, 2016
Full Collection Name
Physics Colloquia
Type
Video
Extent
1 streaming video file
Other Physical Details
digital, sd., col.
Archive
Physics Library
Note
Recorded at a colloquium held on October 24, 2016, sponsored by the Dept. of Physics, University of California, Berkeley.
originally produced as an .mts file in 2016
Speakers: Aron Wall.
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