Chromo-Natural Inflation

I will describe a new model for inflation -
Chromo-Natural Inflation - consisting of an axionic scalar field coupled to a
set of three non-Abelian gauge fields. The model's novel requirement is that
the gauge fields begin inflation with a rotationally invariant vacuum
expectation value (VEV) that is preserved through identification of

SU(2) gauge invariance with rotations in three
dimensions. The gauge VEV interacts with the background value of the axion,
leading to an attractor solution that exhibits slow roll inflation even when
the axion decay constant has a natural value ($<M_{\rm Pl}$).  Assuming a sinusoidal potential for the
axion, inflation continues until the axionic potential vanishes. The speed at
which the axion moves along its potential is modulated by its interactions with
the gauge VEV, rather than being determined by the slope of its potential. Of
the four free parameters in the theory, only one appears tuned: The parameter
that controls the interaction strength between the axion and the gauge fields
must be $\mathcal{O}$(100).

Event Type: 
Scientific Area(s): 
Event Date: 
Jeudi, Décembre 6, 2012 - 11:00 to 12:30
The Space Room (400)
Room #: