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Related papers: Path integral for multi-field inflation

200 papers

One essence in capturing the history of primordial fluctuations that arise during inflation and eventually lead to formation of large scale structures in the universe, relies on quantizing general relativity coupled to a scalar field. This…

High Energy Physics - Theory · Physics 2018-07-24 Gizem Sengor

We develop a frame-covariant formulation of inflation in the slow-roll approximation by generalizing the inflationary attractor solution for scalar-curvature theories. Our formulation gives rise to new generalized forms for the potential…

High Energy Physics - Phenomenology · Physics 2016-06-22 Daniel Burns , Sotirios Karamitsos , Apostolos Pilaftsis

We study the evolution of various measures of quantumness of the curvature perturbation by integrating out the inaccessible entropic fluctuations in the multi-field models of inflation. In particular, we discuss the following measures of…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-17 Rathul Nath Raveendran , Sumanta Chakraborty

We derive general analytic formulae for the power spectrum and spectral index of the curvature perturbation produced during inflation driven by a multi-component inflaton field, up to the second order in the slow-roll approximation. We do…

Astrophysics · Physics 2009-10-28 Takahiro T. Nakamura , Ewan D. Stewart

In this review, we discuss how non-Gaussianity of cosmological perturbations arises from inflation. After introducing the in-in formalism to calculate the $n$-point correlation function of quantum fields, we present the computation of the…

High Energy Physics - Theory · Physics 2014-11-20 Kazuya Koyama

In the present paper, we study the non-Gaussianity of multiple-field inflation model using the method of the field equation. We start from reviewing the background and the perturbation theory of multiple-field inflation, and then derive the…

Astrophysics · Physics 2008-04-04 Shi-Wen Li , Wei Xue

In this paper, we study several issues in the linear equation-of-motion (EoM) and in-in approaches of computing the two-point correlation functions in multi-field inflation. We prove the equivalence between this EoM approach and the…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-20 Xingang Chen , Mohammad Hossein Namjoo , Yi Wang

The latest results from PLANCK impose strong constraints on features in the spectrum of the curvature perturbations from inflation. We analyse the possibility of particle production induced by sharp turns of the trajectory in field space in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Maciej Konieczka , Raquel H. Ribeiro , Krzysztof Turzynski

We show how to construct path integrals for quantum mechanical systems where the space of configurations is a general non-compact symmetric space. Associated with this path integral is a perturbation theory which respects the global…

High Energy Physics - Theory · Physics 2015-06-26 Noah Linden , Malcolm Perry

We derive semi-analytic formulae for the local bispectrum and trispectrum in general two-field inflation and provide a simple geometric recipe for building observationally allowed models with observable non-Gaussianity. We use the \delta N…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Courtney M. Peterson , Max Tegmark

We develop an approach for linking the power spectra, bispectrum, and trispectrum to the geometric and kinematical features of multifield inflationary Lagrangians. Our geometric approach can also be useful in determining when a complicated…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-26 Courtney M. Peterson , Max Tegmark

A perturbative strategy for inflation described by two-inflaton fields is developed using a mathematical analogy with the renormalization-group. Two small quantities, $\alpha$ and $\lambda$, corresponding to standard slow-roll parameters…

High Energy Physics - Theory · Physics 2025-06-10 Bohdan Grzadkowski , Marco Piva

We explore the homogeneous background dynamics and the evolution of generated perturbations of cosmological inflation that is driven by multiple scalar fields interacting with a perfect fluid.Then we apply the method to warm inflation…

General Relativity and Quantum Cosmology · Physics 2018-04-04 Yang-Yang Wang , Jian-Yang Zhu , Xiao-Min Zhang

We solve numerically exactly a simple toy model to quantum general relativity or more properly to path integral on a curved space. We consider the thermal equilibrium of a quantum many body problem on the sphere, the surface of constant…

Quantum Gases · Physics 2026-03-25 Riccardo Fantoni

We investigate non-Gaussianity in general multiple-field inflation using the formalism we developed in earlier papers. We use a perturbative expansion of the non-linear equations to calculate the three-point correlator of the curvature…

Astrophysics · Physics 2009-11-13 G. I. Rigopoulos , E. P. S. Shellard , B. J. W. van Tent

We study the emergence of quantum entanglement in multi-field inflation. In this scenario, the perturbations of one field contribute to the observable curvature perturbation, while multi-field dynamics with the other fields affect the…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Nadia Bolis , Tomohiro Fujita , Shuntaro Mizuno , Shinji Mukohyama

Currently, a method has been developed for the cosmological inflation model with a single scalar field to calculate cosmological parameters such as the power spectrum of scalar and tensor perturbations, their spectral indices, and the…

General Relativity and Quantum Cosmology · Physics 2025-01-06 Katerina Bolshakova , Sergey Chervon

We introduce a numerical method specifically designed for investigating generic multifield models of inflation where a number of scalar fields $\phi^K$ are minimally coupled to gravity and live in a field space with a non-trivial metric…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-14 William Giarè , Mariaveronica De Angelis , Carsten van de Bruck , Eleonora Di Valentino

We revisit an extension of the well-known formalism for gauge-invariant scalar metric fluctuations, to study the spectrums for both, the inflaton and gauge invariant (scalar) metric fluctuations in the framework of a single field…

General Relativity and Quantum Cosmology · Physics 2009-11-13 Mariano Anabitarte , Mauricio Bellini

We perform the analysis of the trispectrum of curvature perturbations generated by the interactions characterizing a general theory of single-field inflation obtained by effective field theory methods. We find that curvature-generated…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Nicola Bartolo , Matteo Fasiello , Sabino Matarrese , Antonio Riotto