Speaker
Dr
Vishagan Sivanesan
(Institut'd Astrophysique de Paris)
Description
Galileon field theory plays an important role in modified
theories of gravity. It arises as the scalar mode in Massive
gravity, DGP
etc and describes the leading order interactions thereby
capturing the
salient features of these theories, such as Vainshtein
screening and
strong coupling. The distinctive aspect of these theories
are that they
possess derivative interactions that are non-linear in the
second
derivative of the field. In [1] the authors generalised the
Galileon field
(0-form) to gauge invariant p-form in a 'direct' way and
found that this
approach yields trivial field equations when p is odd. In
[2] the
existence of theories with non-linearity in the second
derivative of a
gauge invariant vector field was investigated and it was
proved that such
theories do not exist . Here we investigate the existence of
'Galileon
like' theories when p > 1 and odd, using tools from the
representation
theory of the permutation group. Remarkably, we find such
theories do
exist for p>1 in a subtle way, and construct them explicitly
for some
special cases. Moreover, this approach can be considered as
a step towards
the classification of all gauge invariant theories of p-forms.
[1]: 'Arbitrary p-form Galileons' Phys.Rev. D82 (2010) 061501'
[2]: 'A no-go theorem for generalized vector Galileons on
flat spacetime'
JHEP 1404 (2014) 082
