1-5 July 2019
The University of Manchester
Europe/London timezone
- pascos2019@manchester.ac.uk
- +44 (0)161 275 4171
The Local Organising Committee
Attractor inflation beyond the poles
Presented by Dr. Sotirios KARAMITSOS
on
1 Jul 2019
from
15:50
to
16:10
Type: oral presentation
Track: Cosmological Probes
Content
We offer a geometric interpretation of attractor theories with singular kinetic terms as a union of
multiple canonical models. We demonstrate that different domains (separated by poles) can drastically
differ in their phenomenology. We illustrate this with the help of a "master model'' that leads to
distinct predictions depending on which side of the pole the field evolves before examining the more
realistic example of α-attractor models. Such models lead to quintessential inflation within the poles
when featuring an exponential potential. However, beyond the poles, we discover a novel behaviour: the
scalar field responsible for the early-time acceleration of the Universe reaches the boundary of the
field-space manifold, indicating that the theory is incomplete and that a boundary condition must be
imposed in order to determine the late-time behaviour of such theories. Turning to multifield models with
singular kinetic terms, we see that poles generalise straightforwardly to singular curves, which act as
"model walls'' between distinct pole-free inflationary models. As an example, we study a simple two-field
α-attractor-inspired model, whose evolution of isocurvature perturbations is sensitive to where the
non-canonical field begins its trajectory. We finally discuss initial conditions in attractor theories,
where the existence of multiple disconnected canonical models implies that we must make a fundamental
choice: in which domain we impose a distribution for the inflaton in order to then determine the
likelihood of inflation.
Place
Location: Schuster
Room: Annex: Bell Burnell Lecture Theatre