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Related papers: Loop Corrections in Bispectrum in USR Inflation wi…

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The spectrum of primordial fluctuations from inflation can be obtained using a mathematically controlled, and systematically extendable, uniform approximation. Closed-form expressions for power spectra and spectral indices may be found…

Phenomenological studies of cosmological collider physics in recent years have identified many 1-loop inflation correlators as leading channels for discovering heavy new particles around or above the inflation scale. However, complete…

High Energy Physics - Theory · Physics 2023-05-10 Zhong-Zhi Xianyu , Hongyu Zhang

Small-scale scalar perturbations amplified during inflation can induce primordial gravitational waves through tensor-scalar interactions. A long-standing controversial issue is whether the one-loop corrections to tensor perturbations exist…

General Relativity and Quantum Cosmology · Physics 2025-09-03 Cheng-Jun Fang , Han-Wen Hu , Zong-Kuan Guo

Probing correlations among short and long-wavelength cosmological fluctuations is known to be decisive for deepening the current understanding of inflation at the microphysical level. Spectral distortions of the CMB can be caused by…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Emanuela Dimastrogiovanni , Razieh Emami

In loop quantum cosmology, the universe avoids a big bang singularity and undergoes an early and short super-inflation phase. During super-inflation, non-perturbative quantum corrections to the dynamics drive an inflaton field up its…

Astrophysics · Physics 2011-02-23 Shinji Tsujikawa , Parampreet Singh , Roy Maartens

We present a complete one-loop analysis of charged scalar boson pair production in photon-photon collisions, $\gamma\gamma \to H^\pm H^\mp$, within the framework of the Inert Doublet Model (IDM). The calculation is carried out in the…

High Energy Physics - Phenomenology · Physics 2026-04-17 Hamza Abouabid , Abdesslam Arhrib , Jaouad El Falaki , Bin Gong , Qi-Shu Yan

Cosmological $\alpha$-attractors stand out as particularly compelling models to describe inflation in the very early universe, naturally meeting tight observational bounds from cosmic microwave background (CMB) experiments. We investigate…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-22 Laura Iacconi , Hooshyar Assadullahi , Matteo Fasiello , David Wands

Evaluating quantum loop corrections to curvature perturbations in non-attractor inflation presents theoretical ambiguities. A crucial aspect of this challenge lies in the unconstrained finite contributions in renormalization counterterms…

General Relativity and Quantum Cosmology · Physics 2026-05-14 Cheng-Jun Fang , Zong-Kuan Guo

The bispectrum of single-field inflationary trajectories in which the speed of sound of the inflationary trajectories $c_s$ is constant but not equal to the speed of light $c=1$ is explored. The trajectories are generated as random…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-30 Jonathan S. Horner , Carlo R. Contaldi

The observed power spectrum of the cosmic microwave background (CMB) is consistent with inflationary cosmology, which predicts a nearly scale-invariant power spectrum of quantum fluctuations of the inflaton field as they exit the Hubble…

High Energy Physics - Theory · Physics 2007-05-23 Leonard Parker

Based on the stochastic gravity, we study the loop corrections to the scalar and tensor perturbations during inflation. Since the loop corrections to scalar perturbations suffer infrared (IR) divergence, we consider the IR regularization to…

High Energy Physics - Theory · Physics 2010-01-11 Yuko Urakawa , Kei-ichi Maeda

In this paper we compute one-loop corrections to masses and couplings in the minimal supersymmetric standard model. We present explicit formulae for the complete corrections and a set of compact approximations which hold over the unified…

High Energy Physics - Phenomenology · Physics 2009-03-12 Damien M. Pierce , Jonathan A. Bagger , Konstantin T. Matchev , Ren-Jie Zhang

We investigate a model of $R^2$-gravity with a non-minimally coupled scalar field that gives rise to two-stage inflation with a break, that is, with an intermediate stage where inflation momentarily halts. We find that the power spectrum of…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-06 Xinpeng Wang , Ying-li Zhang , Misao Sasaki

We consider the classical attractor regime of the spectator Abelian Higgs model in power-law inflation, and compute the one-loop corrections to its evolution. For computations we utilize dimensional regularization and the propagators in the…

High Energy Physics - Phenomenology · Physics 2024-07-30 Dražen Glavan , Tomislav Prokopec

In this paper, we revisit the linear perturbation (including the comoving curvature perturbation and field perturbation) dynamics in the SR-USR-SR inflation with instantaneous transitions. Using the junction method and asymptotic expansions…

General Relativity and Quantum Cosmology · Physics 2026-02-17 Wen Li , Chao Chen

The era of precision cosmology has allowed us to accurately determine many important cosmological parameters, in particular via the CMB. Confronting Loop Quantum Cosmology with these observations provides us with a powerful test of the…

General Relativity and Quantum Cosmology · Physics 2012-04-06 Ivan Agullo , Abhay Ashtekar , William Nelson

Inflation is often described through the dynamics of a scalar field, slow-rolling in a suitable potential. Ultimately, this inflaton must be identified as the expectation value of a quantum field, evolving in a quantum effective potential.…

High Energy Physics - Phenomenology · Physics 2021-05-11 Jens O. Andersen , Magdalena Eriksson , Anders Tranberg

We calculate the quadra-spectrum and quint-spectrum, corresponding to five and six point correlation functions of the curvature perturbation. For single field inflation with standard kinetic term, the quadra-spectrum and quint-spectrum are…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-16 Chunshan Lin , Yi Wang

We compute the one loop corrections from quantum gravity to the self-mass-squared of a massless, minimally coupled scalar on a locally de Sitter background. The calculation was done using dimensional regularization and renormalized by…

General Relativity and Quantum Cosmology · Physics 2008-11-26 E. O. Kahya , R. P. Woodard

We calculate the one-loop QCD corrections for the decay of an off-shell vector boson with vector couplings into two pairs of quarks of equal or unequal flavours keeping all orders in the number of colours. These matrix elements are relevant…

High Energy Physics - Phenomenology · Physics 2008-11-26 E. W. N. Glover , D. J. Miller
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