Speaker
Garattini Remo
Description
We compute the Zero Point Energy in a spherically
symmetric background distorted at high energy as
predicted by Gravity's Rainbow. In this context we setup
a Sturm-Liouville problem with the cosmological constant
considered as the associated eigenvalue. The
eigenvalue equation is a reformulation of the Wheeler-
DeWitt equation. With the help of a canonical
decomposition, we find that the relevant contribution to
one loop is given by the graviton quantum fluctuations
around the given background. By means of a variational
approach based on gaussian trial functionals, we find
that the ordinary divergences can here be handled by an
appropriate choice of the rainbow's functions, in contrast
to what happens in other conventional approaches. A
generalization including f(R) theories of gravity is
presented, where f(R) is a generic analytic function of
the Ricci curvature scalar R in 4D and in 3D. The explicit
calculation is performed for a Schwarzschild metric. A
final discussion on the connection of our result with the
observed cosmological constant is also reported.
