University
of California, Davis
Physics
Department
Cosmology
Seminar
" Moving Sources in a Ghost Condensate"
Ghost condensation has been recently proposed as a mechanism inducing the spontaneous breaking of Lorentz symmetry. Corrections to the Newton potential generated by a static source have been computed: they can develop on timescales of the order of the age of the Universe, in which case their typical lengthscale is of the order of 1000 km. As a consequence, they propagate at an extremely tiny velocity, whereas every realistic source will be moving at a much larger speed. I will discuss how the gravitational potential is modified if the motion of the source is taken into account. The standard Newton law is recovered in this case, with negligible corrections for any distance from the source up to astrophysical scales. In the absence of a direct coupling of the ghost to matter, signatures of this model will have to be searched in the form of exotic astrophysical events.
Thursday,
May 6, 2004
12:10 p.m., 416 PHY/GEO