275 citations · 1.2k across the 23 of their papers we have counts for
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Cosmic tango between the very small and the very large: Addressing CMB anomalies through Loop Quantum Cosmology
Abhay Ashtekar, Brajesh Gupt, V. Sreenath
While the standard, six-parameter, spatially flat CDM model has been highly successful, certain anomalies in the cosmic microwave background bring out a tension between this mod…
Phenomenology with fluctuating quantum geometries in loop quantum cosmology
Ivan Agullo, Abhay Ashtekar, Brajesh Gupt
The goal of this paper is to probe phenomenological implications of large fluctuations of quantum geometry in the Planck era, using cosmology of the early universe. For the backgro…
Initial conditions for cosmological perturbations
Abhay Ashtekar, Brajesh Gupt
Penrose proposed that the big bang singularity should be constrained by requiring that the Weyl curvature vanishes there. The idea behind this past hypothesis is attractive because…
Quantum Gravity in the Sky: Interplay between fundamental theory and observations
Abhay Ashtekar, Brajesh Gupt
Observational missions have provided us with a reliable model of the evolution of the universe starting from the last scattering surface all the way to future infinity. Furthermore…
Generalized effective description of loop quantum cosmology
Abhay Ashtekar, Brajesh Gupt
The effective description of loop quantum cosmology (LQC) has proved to be a convenient platform to study phenomenological implications of the quantum bounce that resolves the clas…
Phenomenological investigation of a quantum gravity extension of inflation with the Starobinsky potential
Béatrice Bonga, Brajesh Gupt
We investigate the pre-inflationary dynamics of inflation with the Starobinsky potential, favored by recent data from the Planck mission, using techniques developed to study cosmol…
Inflation with the Starobinsky potential in Loop Quantum Cosmology
Béatrice Bonga, Brajesh Gupt
A self-consistent pre-inflationary extension of the inflationary scenario with the Starobinsky potential, favored by Planck data, is studied using techniques from loop quantum cosm…
Numerical evolution of squeezed and non-Gaussian states in loop quantum cosmology
Peter Diener, Brajesh Gupt, Miguel Megevand +1
In recent years, numerical simulations with Gaussian initial states have demonstrated the existence of a quantum bounce in loop quantum cosmology in various models. A key issue per…
Numerical simulations of a loop quantum cosmos: robustness of the quantum bounce and the validity of effective dynamics
Peter Diener, Brajesh Gupt, Parampreet Singh
A key result of isotropic loop quantum cosmology is the existence of a quantum bounce which occurs when the energy density of the matter field approaches a universal maximum close…
Chimera: A hybrid approach to numerical loop quantum cosmology
Peter Diener, Brajesh Gupt, Parampreet Singh
The existence of a quantum bounce in isotropic spacetimes is a key result in loop quantum cosmology (LQC), which has been demonstrated to arise in all the models studied so far. In…
A quantum gravitational inflationary scenario in Bianchi-I spacetime
Brajesh Gupt, Parampreet Singh
We investigate the inflationary model in the Bianchi-I spacetime using effective spacetime description of loop quantum cosmology to understand the issues of the resolution of…
Quantum gravitational Kasner transitions in Bianchi-I spacetime
Brajesh Gupt, Parampreet Singh
Due to non-perturbative quantum gravitational effects, the classical big bang singularity is replaced by a quantum big bounce of the mean scale factor in loop quantization of Bianc…
Contrasting features of anisotropic loop quantum cosmologies: the role of spatial curvature
Brajesh Gupt, Parampreet Singh
A characteristic feature of loop quantization of the isotropic and Bianchi-I spacetimes is the existence of universal bounds on the energy density and the expansion and shear scala…