English
Related papers

Related papers: Inverse volume corrections from loop quantum gravi…

200 papers

This article is devoted to the study of scalar perturbations in loop quantum cosmology. It aims at clarifying the situation with respect to the way initial conditions are set and to the specific choice of an inflaton potential. Several…

General Relativity and Quantum Cosmology · Physics 2018-10-10 Aurélien Barrau , Pierre Jamet , Killian Martineau , Flora Moulin

Recent data suggest that the Universe could be positively curved. Combined with an inflationary stage, this might lead to a curvature bounce instead of the Big Bang. The background evolution is presented, as a function of the parameters…

General Relativity and Quantum Cosmology · Physics 2021-01-20 Cyril Renevey , Aurélien Barrau , Killian Martineau , Selim Touati

We study cosmological tensor perturbations generated during de Sitter inflation in the conformal gravity with mass parameter $m^2=2H^2$. It turns out that tensor power spectrum is scale-invariant.

General Relativity and Quantum Cosmology · Physics 2015-10-21 Yun Soo Myung , Taeyoon Moon

For most initial conditions, cosmologically relevant physical modes were trans-planckian at the bounce time, often by many magnitude orders. We improve the usual loop quantum cosmology calculation of the primordial power spectra -- in the…

General Relativity and Quantum Cosmology · Physics 2018-05-23 Killian Martineau , Aurélien Barrau , Julien Grain

We find several missing one-loop-order contributions in previous considerations about secondary gravitational waves induced at nonlinear order in cosmological perturbations. We consider a consistent perturbative expansion to third-order in…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-03 Chao Chen , Atsuhisa Ota , Hui-Yu Zhu , Yuhang Zhu

We investigate a set of cosmological models for which the primordial power spectrum has a large-scale power deficit. The standard power-law spectrum is subject to long-wavelength modifications described by some new parameters, resulting in…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-13 Sandro D. P. Vitenti , Patrick Peter , Antony Valentini

We consider the k=1 Friedman-Lemaitre-Robertson-Walker (FLRW) model within loop quantum cosmology (LQC), from the perspective of the two available quantization prescriptions. We focus our attention on the existence of the so called `inverse…

General Relativity and Quantum Cosmology · Physics 2016-04-28 Alejandro Corichi , Asieh Karami

We consider the effects of entanglement in the initial quantum state of scalar and tensor fluctuations during inflation. We allow the gauge-invariant scalar and tensor fluctuations to be entangled in the initial state and compute…

High Energy Physics - Theory · Physics 2017-01-13 Nadia Bolis , Andreas Albrecht , R. Holman

Large corrections to the inflationary tensor power spectrum have been speculated to emerge either as second-order scalar-induced classical effects, or as 1-loop quantum corrections. These two sources are not independent of each other.…

High Energy Physics - Phenomenology · Physics 2026-05-28 A. Hauser , M. Laine

After a brief review of the different approaches to predict the possible quantum gravity corrections to quantum field theory, we discuss in some detail the formulation based on a Gaussian reference frame fixing. Then, we implement this…

General Relativity and Quantum Cosmology · Physics 2023-06-12 Giulia Maniccia , Giovanni Montani , Leonardo Torcellini

We consider general relativity with a cosmological constant as a perturbative expansion around a completely solvable diffeomorphism invariant field theory. This theory is the $\Lambda\to\infty$ limit of general relativity. This allows an…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Rodolfo Gambini , Jorge Pullin

In this paper we study the non-Gaussian features of the primordial fluctuations in loop quantum cosmology with the inverse volume corrections. The detailed analysis is performed in the single field slow-roll inflationary models. However,…

General Relativity and Quantum Cosmology · Physics 2012-09-25 Li-Fang Li , Rong-Gen Cai , Zong-Kuan Guo , Bin Hu

Loop quantum gravity introduces two characteristic modifications in the classical constraints of general relativity: the holonomy and inverse-triad corrections. In this paper, a systematic construction of anomaly-free effective constraints…

General Relativity and Quantum Cosmology · Physics 2022-08-12 Asier Alonso-Bardaji , David Brizuela

I present a streamlined review of how the separate universe approach to cosmological perturbation theory can be used to study the dynamics of long-wavelength scalar perturbations in loop quantum cosmology, and then use it to calculate how…

General Relativity and Quantum Cosmology · Physics 2016-08-03 Edward Wilson-Ewing

We estimate fermion loop corrections to the two-point correlation function of primordial tensor perturbations in a slow-roll inflationary background. We particularly compute an explicit term of one-loop correction from a massless fermion,…

High Energy Physics - Theory · Physics 2012-11-22 Kaixi Feng , Yi-Fu Cai , Yun-Song Piao

Although the cosmological perturbations with inverse-volume corrections from loop quantum cosmology have been studied using the anomaly-free algebra approach in much of the literature, there still remains an important issue that some…

General Relativity and Quantum Cosmology · Physics 2018-10-18 Yu Han

We study corrections to the power spectra of curvature and tensor perturbations and the tensor-to-scalar ratio in single field slow roll inflation due to initial conditions imprinted by a fast-roll stage prior to slow roll. For a wide range…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-22 Louis Lello , Daniel Boyanovsky

We study one-loop corrections to the two-point correlation function of tensor perturbations in primordial cosmology induced by massless spectator matter fields. Using the Schwinger-Keldysh formalism in cosmological perturbation theory, we…

General Relativity and Quantum Cosmology · Physics 2020-11-02 H. S. Tan

Recently, it has been claimed that inflationary models with an inflection point in the scalar potential can produce a large resonance in the power spectrum of curvature perturbation. In this paper however we show that the previous analyses…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-06 Cristiano Germani , Tomislav Prokopec

We extend the scalar-tensor reconstruction techniques for classical cosmology frameworks, in the context of loop quantum cosmology. After presenting in some detail how the equations are generalized in the loop quantum cosmology case, we…

General Relativity and Quantum Cosmology · Physics 2016-08-24 V. K. Oikonomou