English
Related papers

Related papers: Differential Equations for Cosmological Correlator…

200 papers

A new phase of temporal evolution of the one-dimensional self-gravitating system is numerically discovered. Fractal structure is dynamically created from non-fractal initial conditions. Implication to astrophysics and mathematical physics…

Astrophysics · Physics 2009-10-31 Hiroko Koyama , Tetsuro Konishi

The theory of cosmological perturbations has become a cornerstone of modern quantitative cosmology since it is the framework which provides the link between the models of the very early Universe such as the inflationary Universe scenario…

High Energy Physics - Theory · Physics 2017-08-23 Robert H. Brandenberger

The gravitational dynamics and cosmological implications of three classes of recently introduced multi-scale spacetimes (with, respectively, ordinary, weighted and q-derivatives) are discussed. These spacetimes are non-Riemannian: the…

High Energy Physics - Theory · Physics 2021-02-15 Gianluca Calcagni

Much of the structure of cosmological correlators is controlled by their singularities, which in turn are fixed in terms of flat-space scattering amplitudes. An important challenge is to interpolate between the singular limits to determine…

High Energy Physics - Theory · Physics 2022-09-21 Daniel Baumann , Wei-Ming Chen , Carlos Duaso Pueyo , Austin Joyce , Hayden Lee , Guilherme L. Pimentel

For a freely evolving granular fluid, the buildup of spatial correlations in density and flow field is described using fluctuating hydrodynamics. The theory for incompressible flows is extended to the general, compressible case, including…

Statistical Mechanics · Physics 2009-10-30 T. P. C. van Noije , M. H. Ernst , R. Brito

We present a set of equations describing the evolution of the scalar-type cosmological perturbation in a gravity with general quadratic order curvature coupling terms. Equations are presented in a gauge ready form, thus are ready to…

General Relativity and Quantum Cosmology · Physics 2011-08-17 H. Noh , J. Hwang

We are investigating if the double copy structure as product of scattering amplitudes of gauge theories applies to cosmological correlators computed in a class of theories for inflation by the operatorial version of the In-In formalism of…

High Energy Physics - Theory · Physics 2020-05-06 A. R. Fazio

We calculate the power spectrum of density fluctuations in the statistical non-equilibrium field theory for classical, microscopic degrees of freedom to first order in the interaction potential. We specialise our result to cosmology by…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-07 Matthias Bartelmann , Felix Fabis , Daniel Berg , Elena Kozlikin , Robert Lilow , Celia Viermann

In this paper, we investigate the evolution of the early universe within an emergent fractional cosmological framework. The underlying formulation is conceptually rooted in generalized measure constructions, closely related to fractal…

General Relativity and Quantum Cosmology · Physics 2026-04-16 S. M. M. Rasouli

It has recently been realized that many theories of physics beyond the Standard Model give rise to cosmological histories exhibiting extended epochs of cosmological stasis. During such epochs, the abundances of different energy components…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-17 Keith R. Dienes , Lucien Heurtier , Fei Huang , Tim M. P. Tait , Brooks Thomas

The general relativistic cosmological Friedmann equations which describe how the scale factor of the universe evolves are expanded explicitly to include energy forms not usually seen. The evolution of the universe as predicted by the…

Astrophysics · Physics 2008-11-26 Robert J. Nemiroff , Bijunath Patla

We follow up on previous work which found that commonly used graph evolution moves lead to conserved quantities that can be expressed in terms of the braiding of the graph in its embedding space. We study non-embedded graphs under three…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Fotini Markopoulou , Isabeau Prémont-Schwarz

A simple set of diagrammatic rules is formulated for perturbative evaluation of ``in-in" correlators, as is needed in cosmology and other nonequilibrium problems. These rules are both intuitive, and efficient for calculational purposes.

High Energy Physics - Theory · Physics 2014-11-21 Steven B. Giddings , Martin S. Sloth

The field equations of modified gravity theories, when considering a homogeneous and isotropic cosmological model, always become autonomous differential equations. This relies on the fact that in such models all variables only depend on…

General Relativity and Quantum Cosmology · Physics 2023-02-03 Christian G. Boehmer , Erik Jensko , Ruth Lazkoz

Any conformally invariant energy associated with a curve possesses tension-free equilibrium states which are self-similar. When this energy is the three dimensional conformal arc-length, these states are the natural spatial generalizations…

Soft Condensed Matter · Physics 2020-01-23 Jemal Guven

We consider the correlation function of an arbitrary number of local observables in quantum field theory. We show that, at tree level in the strong field regime, these correlations arise solely from fluctuations in the initial state. We…

High Energy Physics - Theory · Physics 2017-10-25 Francois Gelis

The degree by which a function can be differentiated need not be restricted to integer values. Usually most of the field equations of physics are taken to be second order, curiosity asks what happens if this is only approximately the case…

General Relativity and Quantum Cosmology · Physics 2014-06-23 Mark D. Roberts

The interplay between cosmology and strongly coupled dynamics can yield transient spectral features that vanish at late times, but which may leave behind phenomenological signatures in the spectrum of primordial fluctuations. Of particular…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-18 Jay Hubisz , Seung J. Lee , He Li , Bharath Sambasivam

We consider a cosmological model starting from (1) the(1+3+6)-dimensional space-times consisting of the outer space (the 3-dimensional expanding section) and the inner space (the 6-dimensional section) and reaching (2) the Friedmann model…

General Relativity and Quantum Cosmology · Physics 2015-12-24 Kenji Tomita

We consider scalar perturbations of energy--density for a class of cosmological models where an early phase of accelerated expansion evolves, without any fine--tuning for graceful exit, towards the standard Friedman eras of observed…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. Capozziello , G. Lambiase , G. Scarpetta