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High Energy Theory Group Seminar: "Massless multi gravity: Covariant, stable, two-derivative interacting massless multi-graviton theories" | The Racah Institute of Physics

High Energy Theory Group Seminar: "Massless multi gravity: Covariant, stable, two-derivative interacting massless multi-graviton theories"

Date: 
Wed, 25/05/201612:00-13:00
Location: 
Kaplun building, Room No. 200
Lecturer: Dr. Idan Talshir
Affiliation: Racah Institute of Physics,
The Hebrew University of Jerusalem
Abstract:
We present a general model of
interacting metric fields with the sum
of massless non-interacting spin 2
fields as the linear limit. In the
noninteracting limit the model is
reduced to a sum of general relativity
actions, with the usual Einstein-
Hilbert kinetic term for each metric
field. Until now the accepted view
was that such theories are
inconsistent since it has been proven
that ghost terms and/or discontinuity
in the number of degrees of freedom
at the zero interaction limit, are
unavoidable. We do not refute these
results, but instead prove by
construction that they do not
necessarily lead to inconsistencies.
In particular, our suggested theories
are: 1. Energetically stable, i.e. their
Hamiltonian is bounded from below
and the multi-Minkowski metric
configuration is the unique ground
state. 2. Continuous in the zero
interaction limit so that general
relativity solutions are restored
smoothly. 3. Include no higher than
two derivative Lagrangian terms. In
addition, the dominant energy
condition is maintained with respect
to all metric fields for all field
configurations.
Additional details of the upcoming
High Energys' seminars
can be found on the following link.