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Related papers: Singularities in Cosmological Loop Correlators

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In this final part of a series of three papers, we will assemble supersymmetric expressions for one-loop correlators in pure-spinor superspace that are BRST invariant, local, and single valued. A key driving force in this construction is…

High Energy Physics - Theory · Physics 2019-09-11 Carlos R. Mafra , Oliver Schlotterer

We study the one loop renormalization in the most general metric-dilaton theory with the second derivative terms only. The general theory can be divided into two classes, models of one are equivalent to conformally coupled with gravity…

High Energy Physics - Theory · Physics 2016-09-06 I. L. Shapiro , Hiroyuki Takata

We derive a cutting rule for equal-time in-in correlators including cosmological correlators based on Keldysh $r/a$ basis, which decomposes diagrams into fully retarded functions and cut-propagators consisting of Wightman functions. Our…

High Energy Physics - Theory · Physics 2024-12-11 Yohei Ema , Kyohei Mukaida

We construct a diagrammatic coaction acting on one-loop Feynman graphs and their cuts. The graphs are naturally identified with the corresponding (cut) Feynman integrals in dimensional regularization, whose coefficients of the Laurent…

High Energy Physics - Theory · Physics 2018-02-02 Samuel Abreu , Ruth Britto , Claude Duhr , Einan Gardi

The analytic structure of non-Gaussian correlators in inflationary cosmologies has recently been proposed as a test of the quantum origin of structure in the universe. To further understand this proposal, we explore the analogous equal-time…

High Energy Physics - Theory · Physics 2022-08-17 Daniel Green , Yiwen Huang

In this article, we explore the structure of IR singularity of Feynman diagrams at one loop via power counting in loop momentum. The emphasis is on many known results which follow from this simple analysis.

High Energy Physics - Phenomenology · Physics 2010-08-27 Ambresh Shivaji

Correlation functions of light scalar fields in de Sitter spacetime, computed via standard perturbation theory, often exhibit secular growth characterized by time-dependent divergent terms in the form of powers of $\ln a(t)$, where $a(t)$…

High Energy Physics - Theory · Physics 2025-01-06 Javier Huenupi , Ellie Hughes , Gonzalo A. Palma , Spyros Sypsas

Generic models of cosmological inflation and the recently proposed scenarios of a recycling universe and the string theory landscape predict spacetimes whose global geometry is a stochastic, self-similar fractal. To visualize the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sergei Winitzki

We generalize Integration-By-Parts (IBP) and differential equations methods to de Sitter correlators related to inflation. While massive correlators in de Sitter spacetime are usually regarded as highly intricate, we find they have…

High Energy Physics - Theory · Physics 2024-10-29 Jiaqi Chen , Bo Feng

We study loop corrections to correlation functions of inflationary perturbations. Previous calculations have found that the two-point function can have a logarithmic running of the form log(k/mu), where k is the wavenumber of the…

High Energy Physics - Theory · Physics 2010-12-09 Leonardo Senatore , Matias Zaldarriaga

We examine scalar quantum electrodynamics in power-law inflation space-time, and compute the one-loop correction to electric and magnetic field correlators at superhorizon separations. The effect at one-loop descends from the coupling of…

General Relativity and Quantum Cosmology · Physics 2024-07-30 Dražen Glavan , Gerasimos Rigopoulos

The space of inflationary models is vast, containing wide varieties of mechanisms, symmetries, and spectra of particles. Consequently, the space of observational signatures is similarly complex. Hence, it is natural to look for boundaries…

High Energy Physics - Theory · Physics 2020-10-29 Daniel Green , Enrico Pajer

We calculate IR divergent graviton one-loop corrections to scalar correlators in de Sitter space, and show that the leading IR contribution may be reproduced via simple semiclassical consistency relations. One can likewise use such…

High Energy Physics - Theory · Physics 2011-01-27 Steven B. Giddings , Martin S. Sloth

We consider an infrared truncated massless minimally coupled scalar field with a quartic self-interaction in the locally de Sitter background of an inflating universe. We compute the two-point correlation function of the scalar at one and…

General Relativity and Quantum Cosmology · Physics 2015-06-03 V. K. Onemli

We use dimensional regularization to evaluate the one loop contribution to the graviton self-energy from a massless, minimally coupled scalar on a locally de Sitter background. For noncoincident points our result agrees with the stress…

General Relativity and Quantum Cosmology · Physics 2011-05-12 Sohyun Park , R. P. Woodard

We study 1-loop corrections to the primordial stochastic background of gravitational waves produced during inflation. While in single-clock, at the leading order in slow-roll, quantum corrections keep the amplitude scale-free this is not…

High Energy Physics - Theory · Physics 2022-02-11 Denis Comelli , Maicol Di Giambattista , Luigi Pilo , Rocco Rollo

In this paper we compute 1-loop corrections to the bispectrum in the decoupling limit of the Effective Field Theory of Inflation (EFToI). We regulate the divergences by employing dimensional regularization and work in $d=3+\delta$…

High Energy Physics - Theory · Physics 2024-10-11 Supritha Bhowmick , Diptimoy Ghosh , Farman Ullah

We combine spectral- and split representations to factorize multi-loop momentum space diagrams, in the Schwinger-Keldysh formulation for cosmological correlators, with massive scalars in the loop. This allows us to extend the resummation of…

High Energy Physics - Theory · Physics 2026-02-11 Jonathan Gräfe , Ivo Sachs

We calculate 1-loop corrections to the Schwinger-Keldysh propagators of Standard-Model-like fields of spin-0, 1/2, and 1, with all renormalizable interactions during inflation. We pay special attention to the late-time divergences of loop…

High Energy Physics - Theory · Physics 2016-08-16 Xingang Chen , Yi Wang , Zhong-Zhi Xianyu

Singularities in General Relativity are regions where the description of spacetime in terms of a pseudo-Riemannian geometry breaks down. The theory seems unable to predict the evolution of the physical degrees of freedom around and beyond…

General Relativity and Quantum Cosmology · Physics 2019-10-16 Flavio Mercati