(invited by Tsvi)
Title: Bimetric MOND gravity
Abstract:
I shall describe a new class of relativistic formulations of MOND in the
form of a bimetric theory, with one metric on which matter moves, and
another, auxiliary metric. The  inter-metric interaction is designed to give
MOND phenomenology in the nonrelativistic limit. The theory involves one
dimensionful constant: the MOND  acceleration constant a0. The theory tends
to GR, with a cosmological constant of order a0^2, in the limit a0 goes to
0. Interestingly, the theory suggests the existence of a putative ``twin
matter'' that couples directly only to the auxiliary metric. I shall discuss
the nonrelativistic limit of the theory, with and without twin matter, as
well as some preliminary results on cosmology and structure formation.