1,105 research outputs found
Generalized Noether symmetry in f(T) gravity
We consider modified teleparallel gravity, (f(T) gravity), as a framework to
explain the present accelerated expansion of the universe. The matter component
is assumed to be cold dark matter. To find the explicit form of the function
, we utilize generalized Noether theorem and use generalized vector fields
as variational symmetries of the corresponding Lagrangian. We study the
cosmological consequences of the obtained results.Comment: 14 pages, 3 figure
Warm inflation with an oscillatory inflaton in the non-minimal kinetic coupling model
In the cold inflation scenario, the slow roll inflation and reheating via
coherent rapid oscillation, are usually considered as two distinct eras. When
the slow roll ends, a rapid oscillation phase begins and the inflaton decays to
relativistic particles reheating the Universe. In another model dubbed warm
inflation, the rapid oscillation phase is suppressed, and we are left with only
a slow roll period during which the reheating occurs. Instead, in this paper,
we propose a new picture for inflation in which the slow roll era is suppressed
and only the rapid oscillation phase exists. Radiation generation during this
era is taken into account, so we have warm inflation with an oscillatory
inflaton. To provide enough e-folds, we employ the non-minimal derivative
coupling model. We study the cosmological perturbations and compute the
temperature at the end of warm oscillatory inflation.Comment: 22 pages, typos fixed, accepted by EPJ
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