Speaker
Fawad Hassan
(Stockholm University)
Description
The interactions of the gravitational metric with other spin-2 fields are strongly constrained by the absence of the so called ghost instabilities in the theory. Although the study of such ghost free interactions are well motivated theoretically, their construction and even the question of their existence have been long standing problems. I will motivate the study of such theories and then describe the ghost free theories of two interacting spin-2 fields (bimetric theories) and their known extensions to multiple spin-2 fields (multimetric theories). I will also comment on some implications and on the basic geometry of spacetime in such theories.
Primary author
Fawad Hassan
(Stockholm University)
