Fredagskollokvium: Massive gravity and cosmology

 The search for a consistent theory of finite-range gravity
is a longstanding problem and well motivated by both theoretical and
observational considerations. On the theoretical side, whether there
exists such a consistent extension of general relativity by a mass
term is a basic question of classical field theory. After Fierz and
Pauli's pioneering attempt in 1939, this issue has been attracting a
great deal of interest. On the observational side, continuing
experimental probes of gravity have revealed new unexpected phenomena
at large scales. One of the most profound discovery is the cosmic
acceleration, which was found in 1998. The extremely tiny energy-scale
associated with the cosmic acceleration hints that gravity might need
to be modified in the infrared. The massive gravity is one of the most
interesting attempts in this direction. In this talk, after reviewing
the history and recent developments of massive gravity, I will
describe cosmological solutions and their stability.