This workshop dealt with various "analog models" for GR. These analog models include acoustics in flowing fluids, quasi-particles in superfluids, flowing Bose-Einstein condensates, slow light in flowing fluids, nonlinear electrodynamics, the Scharnhorst effect, and more.
The common theme in all these analog models is the presence of an effective Lorentzian metric that governs perturbative fluctuations and/or quasi-particles. This effective metric forces the fluctuations to exhibit many of the kinematic features of general relativity, though dynamic features [those specifically based on the Einstein-Hilbert action] typically do not carry over.
It seems plausible that we might be able to construct analog horizons
in the laboratory in the not too distant future. Such analog horizons
are expected to exhibit Hawking radiation, but possibly without any
analog of Bekenstein entropy. Analog models of GR are useful probes
of Hawking radiation: Because the short-distance physics is explicitly
known (atomic physics), the cutoff is physically understood---this
helps clarify the role of trans-Planckian frequencies in GR, which in
these condensed-matter GR analogs are replaced by "trans-Bohrian"
physics.
Comments to:
visser@mcs.vuw.ac.nz