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Nonperturbative effects in event shape distributions can be characterized by shape functions derived in the eikonal approximation or, equivalently, from soft-collinear effective theory. The use of energy flow operators and the boost…

High Energy Physics - Phenomenology · Physics 2014-11-18 Christopher Lee , George Sterman

We perform adiabatic regularization of power spectrum in nonminimally coupled general single-field inflation with varying speed of sound. The subtraction is performed within the framework of earlier study by Urakawa and Starobinsky dealing…

General Relativity and Quantum Cosmology · Physics 2018-03-15 Allan L. Alinea , Takahiro Kubota

We develop a gauge-invariant formalism for the study of density perturbations in a Friedmann-Robertson-Walker universe with multiple interacting fluids and/or scalar fields. We show how N scalar fields may be described by N kinetic fluids…

Astrophysics · Physics 2009-11-10 Karim A. Malik , David Wands

We consider models of inflation that contain a transient non-slow-roll stage and investigate the conditions under which a dip appears in the power spectrum of the curvature perturbation. Using the $\delta N$ formalism, we derive a general…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-19 Tomohiro Fujita , Ryodai Kawaguchi , Misao Sasaki , Yuichiro Tada

We present a method for suppressing contributions from higher-order terms in perturbation theory, greatly increasing the amount of information which may be extracted from the matter power spectrum. In an evolved cosmological density field…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-30 Fergus Simpson , Alan F. Heavens , Catherine Heymans

We theoretically study nonadiabatic corrections for charge pumping in a noninteracting electron model of a single-level quantum dot. We derive a formula for the velocity limit of parameter driving to realize adiabatic pumping and illustrate…

Mesoscale and Nanoscale Physics · Physics 2022-06-15 Masahiro Hasegawa , Takeo Kato

In a typical scenario the diagrammatic many-body perturbation theory generates asymptotic series. Despite non-convergence, the asymptotic expansions are useful when truncated to a finite number of terms. This is the reason for popularity of…

Strongly Correlated Electrons · Physics 2016-01-19 Yaroslav Pavlyukh , Jamal Berakdar , Angel Rubio

We consider a dark energy fluid with arbitrary sound speed and equation of state and discuss the effect of its clustering on the cold dark matter distribution at the non-linear level. We write the continuity, Euler and Poisson equations for…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Stefano Anselmi , Guillermo Ballesteros , Massimo Pietroni

Two-parameter perturbation theory is a scheme tailor-made to consistently include nonlinear density contrasts on small scales ($<100\; \mathrm{Mpc}$), whilst retaining a traditional approach to cosmological perturbations in the…

General Relativity and Quantum Cosmology · Physics 2020-03-18 Christopher Gallagher , Timothy Clifton , Chris Clarkson

We discuss dissipative stochastic wave and diffusion equations resulting from an interaction of the inflaton with an environment in an external expanding metric. We show that a diffusion equation well approximates the wave equation in a…

General Relativity and Quantum Cosmology · Physics 2020-06-25 Z. Haba

We derive a non-perturbative equation for the large scale structure power spectrum of long-wavelength modes. Thereby, we use an operator product expansion together with relations between the three-point function and power spectrum in the…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-19 Mathias Garny , Thomas Konstandin , Rafael A. Porto , Laura Sagunski

Distances in cosmology are usually inferred from observed redshifts - an estimate that is dependent on the local peculiar motion - giving a distorted view of the three dimensional structure and affecting basic observables such as the…

Astrophysics · Physics 2008-12-18 J. Richard Shaw , Antony Lewis

The adaptive perturbation chooses a non-standard decomposition. The Hamiltonian becomes a sum of solvable and perturbation parts. We calculate the spectrum using the adaptive perturbation method at the leading-order to compare to numerical…

Quantum Physics · Physics 2021-07-08 Chen-Te Ma

The large scale structure bispectrum in the squeezed limit couples large with small scales. Since relativity is important at large scales and non-linear loop corrections are important at small scales, the proper calculation of the observed…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-24 Lina Castiblanco , Radouane Gannouji , Jorge Noreña , Clément Stahl

We find statistically significant correlations in the cosmological matter power spectrum over the full range of observable scales. While the correlations between individual modes are weak, the band-averaged power spectrum shows strong…

Astrophysics · Physics 2009-10-31 A. Meiksin , Martin White

We study the on-shell scattering amplitudes in quantum gravity for high-energy collisions in the eikonal approximation. We first evaluate the $n$-loop 2-particle scattering amplitude in the high energy and low momentum transfer limit. We do…

High Energy Physics - Theory · Physics 2023-12-04 Shreya Shrivastava

The coupled cluster iteration scheme is analysed as a multivariate discrete-time map using nonlinear dynamics and synergetics. The nonlinearly coupled set of equations to determine the cluster amplitudes are driven by a fraction of the…

Computational Physics · Physics 2021-10-13 Valay Agarawal , Chayan Patra , Rahul Maitra

The two-point summary statistics is one of the most commonly used tools in the study of cosmological structure. Starting from the theoretical power spectrum defined in the 3D volume and obtained via the process of ensemble averaging, we…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-02 Alvise Raccanelli , Zvonimir Vlah

We investigate one-loop quantum corrections to the power spectrum of adiabatic perturbation from entropy modes/adiabatic mode cross-interactions in multiple DBI inflationary models. We find that due to the non-canonical kinetic term in DBI…

High Energy Physics - Theory · Physics 2010-04-07 Xian Gao , Fanrong Xu

We use CMB (WMAP and ACBAR), large scale structure (SDSS luminous red galaxies) and supernova (SNLS) data to constrain the possible contribution of CDM isocurvature modes to the primordial perturbation spectrum. We consider three different…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-09 Ian Sollom , Anthony Challinor , Michael P. Hobson
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