RT Journal Article
T1 The Effect of a Positive Cosmological Constant on the Bounce of Loop Quantum Cosmology
A1 Martín Benito, Mercedes
A1 Neves, Rita B.
AB We provide an analytical solution to the quantum dynamics of a flat Friedmann-Lemaître- Robertson-Walker model with a massless scalar field in the presence of a small and positive cosmological constant, in the context of Loop Quantum Cosmology. We use a perturbative treatment with respect to the model without a cosmological constant, which is exactly solvable. Our solution is approximate, but it is precisely valid at the high curvature regime where quantum gravity corrections are important. We compute explicitly the evolution of the expectation value of the volume. For semiclassical states characterized by a Gaussian spectral profile, the introduction of a positive cosmological constant displaces the bounce of the solvable model to lower volumes and to higher values of the scalar field. These displacements are state dependent, and in particular, they depend on the peak of the Gaussian profile, which measures the momentum of the scalar field. Moreover, for those semiclassical states, the bounce remains symmetric, as in the vanishing cosmological constant case. However, we show that the behavior of the volume is more intricate for generic states, leading in general to a non-symmetric bounce.
PB MDPI
SN 2227-7390
YR 2020
FD 2020-02-04
LK https://hdl.handle.net/20.500.14352/8100
UL https://hdl.handle.net/20.500.14352/8100
LA eng
NO Ministerio de Ciencia e Innovación (MICINN)/FEDER
NO Fundação para a Ciência e a Tecnologia (FCT)
DS Docta Complutense
RD 23 abr 2025