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We present a hypothesis for the universal properties of operators evolving under Hamiltonian dynamics in many-body systems. The hypothesis states that successive Lanczos coefficients in the continued fraction expansion of the Green's…

Statistical Mechanics · Physics 2019-10-25 Daniel E. Parker , Xiangyu Cao , Alexander Avdoshkin , Thomas Scaffidi , Ehud Altman

Bosonic two-mode squeezed states are paradigmatic entangled Gaussian states that have wide utility in quantum information and metrology. Here, we show that the basic structure of these states can be generalized to arbitrary bipartite…

Quantum Physics · Physics 2025-02-27 Mikhail Mamaev , Martin Koppenhöfer , Andrew Pocklington , Aashish A. Clerk

We use a numerical code for accurate computation of the amplitude of linear density perturbations and gravitational waves generated by single-field inflation models to study the accuracy of existing analytic results based on the slow-roll…

Astrophysics · Physics 2009-10-28 Ian J Grivell , Andrew R Liddle

We study the planar regime of curvature perturbations for single field inflationary models in an axially symmetric Bianchi I background. In a theory with standard scalar field action, the power spectrum for such modes has a pole as the…

High Energy Physics - Theory · Physics 2014-06-13 Anindya Dey , Ely D. Kovetz , Sonia Paban

We investigate a calculation method for solving the Mukhanov-Sasaki equation in slow-roll $k$-inflation based on the uniform approximation (UA) in conjunction with an expansion scheme for slow-roll parameters with respect to the number of…

General Relativity and Quantum Cosmology · Physics 2016-07-18 Allan L. Alinea , Takahiro Kubota , Wade Naylor

The evolution of gauge invariant second-order scalar perturbations in a general single field inflationary scenario are presented. Different second order gauge invariant expressions for the curvature are considered. We evaluate…

General Relativity and Quantum Cosmology · Physics 2008-11-26 F. Finelli , G. Marozzi , G. P. Vacca , G. Venturi

We present an inflationary model preceded by a bounce in a metric theory a l\'{a} $f(R)$ where $R$ is the scalar curvature of the space-time. The model is asymptotically de Sitter such that the gravitational action tends asymptotically to a…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-05 Mariam Bouhmadi-Lopez , Joao Morais , Alfredo B. Henriques

The GW approximation is widely used for reliable and accurate modeling of single-particle excitations. It also serves as a starting point for many theoretical methods, such as its use in the Bethe-Salpeter equation (BSE) and dynamical…

Computational Physics · Physics 2024-03-25 Weiwei Gao , Zhao Tang , Jijun Zhao , James R. Chelikowsky

The large-scale power deficit in the cosmic microwave background fluctuations might be relevant with the physics of pre-inflation, a bounce, or a superinflationary phase preceding slow-roll inflation, which can provide a singular-free…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-15 Yong Cai , Yu-Tong Wang , Yun-Song Piao

The full set of cosmological observables coming from linear scalar and tensor perturbations of loop quantum cosmology is computed in the presence of inverse-volume corrections. Background inflationary solutions are found at linear order in…

General Relativity and Quantum Cosmology · Physics 2011-03-28 Martin Bojowald , Gianluca Calcagni

We revisit a two-component inflaton model with a turning trajectory in the field space, where the field slowly rolls down along the trajectory. We consider the case when the effective mass in the direction perpendicular to the trajectory,…

High Energy Physics - Theory · Physics 2012-11-09 Shi Pi , Misao Sasaki

We study a simple extension of Linde's hybrid inflation model, with the inflaton mass term replaced by the most general renormalizable potential for $\phi$. The unprocessed power spectrum of density perturbations can have two minima and one…

Astrophysics · Physics 2009-10-22 Yun Wang

Assuming only a known dispersion relation of a single mode in the spectrum of a meromorphic two-point function (in the complex frequency plane at fixed wavevector) in some quantum field theory, we investigate when and how the reconstruction…

High Energy Physics - Theory · Physics 2023-02-15 Sašo Grozdanov , Timotej Lemut

The maximum amount of entanglement achievable under passive transformations by continuous-variable states is called the entanglement potential. Recent work has demonstrated that the entanglement potential is upper-bounded by a simple…

Quantum Physics · Physics 2023-07-24 Bohan Li , Aritra Das , Spyros Tserkis , Prineha Narang , Ping Koy Lam , Syed M. Assad

We propose a new approach for calculating the curvature perturbations produced during inflation in the stochastic formalism. In our formalism, the fluctuations of the e-foldings are directly calculated without perturbatively expanding the…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-06 Tomohiro Fujita , Masahiro Kawasaki , Yuichiro Tada , Tomohiro Takesako

We study the impact of the use of the power series expression for the primordial tensor spectrum on parameter estimation from future direct detection gravitational wave experiments. The spectrum approximated by the power series expansion…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Sachiko Kuroyanagi , Tomo Takahashi

We consider the large-N Calogero model in the \h\ collective-field approach based on the $1/N$ expansion. The Bogomol'nyi limit appears and the corresponding equation for the semiclassical configuration gives the correct ground-state…

High Energy Physics - Theory · Physics 2008-02-03 I. Andrić , V. Bardek , L. Jonke

We study an inflationary model driven by a single minimally coupled standard kinetic term scalar field with a step in its mass modeled by an Heaviside step function. We present an analytical approximation for the mode function of the…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-04 Frederico Arroja , Antonio Enea Romano , Misao Sasaki

We study the classic hybrid inflation model in its original and modified forms and show the shape of the inflationary potentials and analyze the amount of primordial gravitational waves each model predicts. We compare the resulting EE-mode…

General Relativity and Quantum Cosmology · Physics 2021-09-01 N. Malsawmtluangi

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