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Related papers: Holography for Cosmology

200 papers

It has recently been suggested that a strongly coupled phase of inflation may be described holographically in terms of a weakly coupled quantum field theory (QFT). Here, we explore the possibility that the wave function of an inflationary…

High Energy Physics - Theory · Physics 2015-06-15 Jaume Garriga , Yuko Urakawa

Previously defined covariant and gauge-invariant perturbation variables, representing, e.g., the fractional spatial energy density gradient on hypersurfaces of constant expansion, are used to simplify the linear perturbation analysis of a…

Astrophysics · Physics 2009-10-30 Winfried Zimdahl

Cosmic inflation provides a window to the highest energy densities accessible in nature, far beyond those achievable in any realistic terrestrial experiment. Theoretical insights into the inflationary era and its observational probes may…

In this paper the relevance of holographic entropy bounds in the context of inflation is investigated. We distinguish between entropy on large and small scales and confront the entropy of quantum fluctuations in an inflating cosmology with…

High Energy Physics - Theory · Physics 2009-11-10 Ulf H. Danielsson

We investigate the holographic quantum entanglement of a visible universe in an inflationary cosmology. To do so, we consider an AdS space with a dS boundary which represents an expanding space in time. In an inflationary cosmology, there…

High Energy Physics - Theory · Physics 2018-06-05 Seoktae Koh , Jung Hun Lee , Chanyong Park , Daeho Ro

We quantize to completion an inflationary universe with small inhomogeneities in the framework of loop quantum cosmology. The homogeneous setting consists of a massive scalar field propagating in a closed, homogeneous scenario. We provide a…

General Relativity and Quantum Cosmology · Physics 2012-07-20 Mikel Fernández-Méndez , Guillermo A. Mena Marugán , Javier Olmedo

We show that standard puzzles of hot Big Bang cosmology that motivated the introduction of cosmological inflation, such as the smoothness and horizon problem, the flatness problem and the relic problem are also solved by holographic models…

High Energy Physics - Theory · Physics 2020-01-29 Horatiu Nastase , Kostas Skenderis

We propose a new four-parameter entropy function that generalizes the Tsallis, R\'{e}nyi, Barrow, Sharma-Mittal, Kaniadakis and Loop Quantum Gravity entropies for suitable limits of the parameters. Consequently, we address the early and…

General Relativity and Quantum Cosmology · Physics 2022-06-15 Shin'ichi Nojiri , Sergei D. Odintsov , Tanmoy Paul

We analyse slow-roll inflationary cosmologies that are holographically dual to a three-dimensional conformal field theory deformed by a nearly marginal scalar operator. We show the cosmological power spectrum is inversely proportional to…

High Energy Physics - Theory · Physics 2013-10-15 Paul McFadden

The early universe according to the big bang and the grand unified theories is discussed. The shortcomings of big bang are summarized together with their resolution by inflationary cosmology. Inflation, the subsequent oscillation and decay…

High Energy Physics - Phenomenology · Physics 2007-05-23 George Lazarides

In this note we show explicitly that, applying an extension of Maldacena's map for the wavefunction of the Universe $Z[\phi]=\Psi[\phi]$ from de Sitter inflation to holographic cosmology, we find the relations previously derived for 2-point…

High Energy Physics - Theory · Physics 2023-08-29 Matheus Cravo , Horatiu Nastase

The most radical version of the holographic principle asserts that all information about physical processes in the world can be stored on its surface. This formulation is at odds with inflationary cosmology, which implies that physical…

High Energy Physics - Theory · Physics 2009-09-29 Nemanja Kaloper , Andrei Linde

We interpret cosmological evolution holographically as a renormalisation group flow in a dual Euclidean field theory, as suggested by the conjectured dS/CFT correspondence. Inflation is described by perturbing around the infra-red fixed…

High Energy Physics - Theory · Physics 2009-11-07 Finn Larsen , Jan Pieter van der Schaar , Robert G. Leigh

This essay outlines the Holographic Space-time (HST) theory of cosmology and its relation to conventional theories of inflation. The predictions of the theory are compatible with observations, and one must hope for data on primordial…

High Energy Physics - Theory · Physics 2018-12-19 T. Banks , W. Fischler

The linear cosmological perturbation theory of almost homogeneous and isotropic perfect fluid and scalar field universes is reconsidered and formally simplified. Using the existence of a covariant conserved quantity on large perturbation…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Winfried Zimdahl

Inflationary cosmology provides a natural mechanism for the generation of primordial perturbations which seed the formation of observed cosmic structure and lead to specific signals of anisotropy in the cosmic microwave background…

Astrophysics · Physics 2011-07-19 Salman Habib , Andreas Heinen , Katrin Heitmann , Gerard Jungman

The early stages of the universe evolution are discussed according to the hot big bang model and the grand unified theories. The shortcomings of big bang are summarized and their resolution by inflationary cosmology is sketched.…

High Energy Physics - Phenomenology · Physics 2008-11-26 George Lazarides

We discuss the validity of the holographic principle in a $(4+n)$ dimensional universe in an asymmetric inflationary phase.

High Energy Physics - Theory · Physics 2009-10-31 Elcio Abdalla , L. Alejandro Correa-Borbonet

A new version of holographic principle for cosmology is proposed, which dictates that particle entropy within `cosmological apparent horizon' should not exceed gravitational entropy associated with the apparent horizon. It is shown that, in…

High Energy Physics - Theory · Physics 2010-04-06 Dongsu Bak , Soo-Jong Rey

We propose a method to extract predictions from quantum cosmology for inflation that can be confronted with observations. Employing the tunneling boundary condition in quantum geometrodynamics, we derive a probability distribution for the…

General Relativity and Quantum Cosmology · Physics 2015-07-21 Gianluca Calcagni , Claus Kiefer , Christian F. Steinwachs