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Quantum Effects in Strong, Classical Potentials

Friday, October 21, 2016

Dark Energy and Condensate Stars: A Massless Scalar in Low Energy Gravity

This week we had a really interesting colloquium talk by Dr. Emil Mottola, from the Theory Division at Los Alamos National Laboratory on black holes, some of their theoretical issues and the possibility of a massless scalar particle in low energy gravity that might also couple to (if weakly) and therefore be detectable, by QED.
It was great to see a really nice discussion develop after the talk, especially with quite a few of the grad students in the audience
Below is the full abstract for Emil's talk and I hope to be able to post the slides soon.




Colloquium
October 19, 2016
John Archibald Wheeler Lecture Hall
RLM 4.102, 4:00 pm

“Dark Energy and Condensate Stars: A Massless
Scalar in Low Energy Gravity”
Dr. Emil Mottola
Los Alamos National Laboratory

Abstract

With the impressive success of both the Standard Model of Particle Physics and Einstein's Theory of General Relativity (GR) comes the need comes the need for bridging the gulf between them. This need is most acute in understanding the physics of black 'holes,' and the nature and magnitude of cosmological vacuum dark energy, both of which suggest something is missing in low energy gravity coupled to the quantum vacuum. By methods of Effective Field Theory one does find quantum corrections to classical gravity from the conformal anomaly of massless or nearly massless fields in curved space, which leads to a pair-correlated massless scalar not present in classical GR. It is suggested that this conformal anomaly scalar can have macroscopically large effects on black 'holes,' replacing their classical horizons with
a quantum boundary layer, where the effective value of the gravitational vacuum energy density can change. In the effective theory, the cosmological term becomes a dynamical condensate, whose value in the interior depends upon boundary conditions near the horizon. The resulting gravitational condensate star configuration resolves all black hole paradoxes, and provides a testable alternative to black holes as the final state of complete gravitational collapse. The observed dark energy of our universe likewise may be a macroscopic finite size effect whose value depends not on microphysics but on the cosmological horizon scale. The possibility of producing and/or detecting the scalar 'conformalon' of low energy gravity by its axion-like coupling to two photons in terrestrial experiments, including by high power lasers will be discussed.