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Related papers: Bootstrapping Large Graviton non-Gaussianities

200 papers

We use astrophysical data to shed light on fundamental physics by constraining parametrized theoretical cosmological and gravitational models. Gravitational parameters are those constants that parametrize possible departures from Einstein's…

Astrophysics · Physics 2008-08-18 Yi Mao

We revisit the squeezed-limit non-Gaussianity in the single-field non-attractor inflation models from the viewpoint of the cosmological soft theorem. In the single-field attractor models, inflaton's trajectories with different initial…

High Energy Physics - Theory · Physics 2023-12-06 Teruaki Suyama , Yuichiro Tada , Masahide Yamaguchi

In [1], a most general higher curvature non-local gravity action was derived that admits a particular $R^2$-like inflationary solution predicting the spectral index of primordial scalar perturbations $n_s(N)\approx 1-\frac{2}{N}$, where $N$…

High Energy Physics - Theory · Physics 2023-07-18 Alexey S. Koshelev , K. Sravan Kumar , Alexei A. Starobinsky

Bootstrapped Newtonian gravity was developed with the purpose of estimating the impact of quantum physics in the nonlinear regime of the gravitational interaction, akin to corpuscular models of black holes and inflation. In this work, we…

General Relativity and Quantum Cosmology · Physics 2021-02-22 Roberto Casadio , Andrea Giusti

Observations of the Cosmic Microwave Background (CMB) have cemented the notion that the large-scale Universe is both statistically homogeneous and isotropic. But is it invariant also under reflections? To probe this we require…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-25 Oliver H. E. Philcox

Studying the primordial non-Gaussianity of inflationary perturbations is crucial for testing the inflation paradigm of the early universe. In this work, we conduct a comprehensive analysis of the angular bispectrum and trispectrum of…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-30 Jun-Peng Li , Sai Wang , Zhi-Chao Zhao , Kazunori Kohri

Very few explicit inflationary scenarios are known to generate a large bispectrum of orthogonal shape. Dirac-Born-Infeld Galileon inflation, in which an induced gravity term is added to the DBI action, is one such model. We formulate it in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Sebastien Renaux-Petel

In arXiv:0908.4089, we have proposed a model where natural inflation is realized on a steep potential as a consequence of the interaction of the inflaton with gauge fields through an axion-like coupling. In the present work we study the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Mohamed M. Anber , Lorenzo Sorbo

We extend the \delta N formalism so that it gives all of the stochastic properties of the primordial curvature perturbation \zeta if the initial field perturbations are gaussian. The calculation requires only the knowledge of some family of…

Astrophysics · Physics 2011-06-08 David H. Lyth , Yeinzon Rodriguez

We investigate primordial tensor non-Gaussianity in single field inflation, during a phase of non-attractor evolution when the spectrum of primordial tensor modes can be enhanced to a level detectable at interferometer scales. Making use of…

High Energy Physics - Theory · Physics 2019-09-25 Ogan Ozsoy , Maria Mylova , Susha Parameswaran , Cari Powell , Gianmassimo Tasinato , Ivonne Zavala

We develop a mathematical construction of non-Gaussian fields whose bispectra satisfy the single-clock inflation consistency relation. At the same order that our basis for bispectra recovers the two simplest single clock templates, we also…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-17 Bekir Baytaş , Sarah Shandera

Future measurements of primordial non-Gaussianity can reveal cosmologically produced particles with masses of order the inflationary Hubble scale and their interactions with the inflaton, giving us crucial insights into the structure of…

High Energy Physics - Phenomenology · Physics 2018-05-15 Soubhik Kumar , Raman Sundrum

The tree-level wavefunction coefficient for four gravitons in de Sitter space was recently bootstrapped using the Cosmological Optical Theorem, flat space limit, and Manifestly Local Test \cite{Bonifacio:2022vwa}. Inspired by the double…

High Energy Physics - Theory · Physics 2023-09-04 Connor Armstrong , Harry Goodhew , Arthur Lipstein , Jiajie Mei

We derive bounds on Wilson coefficients in gravitational effective field theories using fully crossing symmetric dispersion relations. These sum rules naturally isolate finite subsets of low-energy couplings without relying on the forward…

High Energy Physics - Theory · Physics 2026-05-26 Celina Pasiecznik

We obtain a new 3D gravity model from two copies of parity-odd Einstein-Cartan theories. Using Hamiltonian analysis, we demonstrate that the only local degrees of freedom are two massive spin-2 modes. Unitarity of the model in anti-de…

High Energy Physics - Theory · Physics 2019-07-19 Mehmet Ozkan , Yi Pang , Utku Zorba

Modifications of general relativity provide an alternative explanation to dark energy for the observed acceleration of the universe. We calculate quasilinear effects in the growth of structure in f(R) models of gravity using perturbation…

Astrophysics · Physics 2009-10-29 Alex Borisov , Bhuvnesh Jain

We employ an unregulated computation the graviton self-energy from gravitons on de Sitter background to infer the renormalized result. This is used to quantum-correct the linearized Einstein equation. We solve this equation for the…

General Relativity and Quantum Cosmology · Physics 2022-07-11 L. Tan , N. C. Tsamis , R. P. Woodard

We construct invariant differential operators acting on sections of vector bundles of densities over a smooth manifold without using a Riemannian metric. The spectral invariants of such operators are invariant under both the diffeomorphisms…

High Energy Physics - Theory · Physics 2009-11-10 Ivan G. Avramidi

We consider a simple inflation model with a complex scalar field coupled to gravity non-minimally. Both the modulus and the angular directions of the complex scalar are slowly rolling, leading to two-field inflation. The modulus direction…

High Energy Physics - Phenomenology · Physics 2015-05-28 Jinn-Ouk Gong , Hyun Min Lee

A scale-invariant universe can have a period of accelerated expansion at early times: inflation. We use a frame-invariant approach to calculate inflationary observables in a scale invariant theory of gravity involving two scalar fields -…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-26 Pedro G. Ferreira , Christopher T. Hill , Johannes Noller , Graham G. Ross