Departamento de Física

Facultad de Ciencia
Universidad de Santiago de Chile

Seminario Altas Energías y Gravitación: Inflación sin Inflatón

Fecha: 
04/12/2017 - 13:00

Título: Inflation without Inflaton

Dr. Jorge Gamboa
Departamento de Física
Universidad de Santiago de Chile

Abstract:
The interaction between two  initially causally disconnected regions of  the  universe  is  studied using  analogies  of  non-commutative quantum  mechanics  and  deformation of  Poisson  manifolds.   These causall disconnect   regions  are  governed  by   two  independent Friedmann-Lema\^{\i}tre-Robertson-Walker  (FLRW) metrics  with scale factors  $a$  and $b$  and  cosmological  constants $\Lambda_a$  and $\Lambda_b$. The  interaction between causally  disconnected regions is   turn   on  by   positing   the   non-trivial  Poisson   bracket $[ {\cal  P}_{\alpha}, {\cal P}_{\beta} ]  = \epsilon_{\alpha \beta} \frac{\kappa}{G}   $,  where   $G$  is   the  Newton  constant  and $\kappa \ll 1$ is a dimensionless parameter.  The modified FLRW equations are found  and we show that in the  RHS of both equations, there are  special combinations  of $a (t)$  and $b  (t)$ consistentwith  the conservation  of  the full  energy  momentum tensor.   The system of coupled  equations is solved by  using perturbation theory at first order  in $\kappa$ and we show how  $a(t)$ can experience a rapid  expansion  due to  the  combination  between $\Lambda_a$  and $\Lambda_b$  without  needing an  extra  scalar  field.  After  this inflation  the universe  can expand  as in  the present  epoch, {\it  i.e.} even  though $\Lambda_a$ can  be very small,  but satisfying $\frac{\Lambda_a}{\Lambda_b}  \ll1$, we  conclude that  the universe accelerate basically by the presence of $\Lambda_b$.

Miércoles 12 de abril 2017
a las 13:00 hrs.
Sala de Conferencias 3er Piso
Departamento de Física
Universidad de Santiago de Chile

Carrera: 
Doctorado en Ciencia con Mención en Física