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相关论文: Loop quantum cosmology: The horizon problem and th…

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We point out that the horizon problem encountered in standard text-books or review papers on cosmology is, in general, derived for world models based on Robertson-Walker line element where homogeneity and isotropy of the universe -- \`a la…

广义相对论与量子宇宙学 · 物理学 2024-04-18 Ashok K. Singal

Loop quantum cosmology (LQC) provides promising resolutions to the trans-Planckian issue and initial singularity arising in the inflationary models of general relativity. In general, due to different quantization approaches, LQC involves…

广义相对论与量子宇宙学 · 物理学 2015-12-10 Tao Zhu , Anzhong Wang , Gerald Cleaver , Klaus Kirsten , Qin Sheng , Qiang Wu

Anomaly-free perturbations of loop quantum cosmology with holonomy corrections reveal an $\Omega$ -deformed spacetime structure, $\Omega:=1-2\rho/\rho_c$, where $\Omega<0$ indicates a Euclidean-like space and $\Omega>0$ indicates a…

广义相对论与量子宇宙学 · 物理学 2016-12-21 Long Chen , Jian-Yang Zhu

Non-perturbative corrections from loop quantum cosmology (LQC) to the scalar matter sector is already known to imply inflation. We prove that the LQC modified scalar field generates exponential inflation in the small scale factor regime,…

广义相对论与量子宇宙学 · 物理学 2009-11-10 Ghanashyam Date , Golam Mortuza Hossain

In this paper we discuss the inflationary universe in the context of a Chaplygin gas equation of state within the framework of the effective theory of loop quantum cosmology. Under the slow-roll approximation, we calculate the primordial…

广义相对论与量子宇宙学 · 物理学 2009-08-20 Xin Zhang , Jingfei Zhang , Jinglei Cui , Li Zhang

Loop quantum cosmology of the closed isotropic model is studied with a special emphasis on a comparison with traditional results obtained in the Wheeler-DeWitt approach. This includes the relation of the dynamical initial conditions with…

广义相对论与量子宇宙学 · 物理学 2009-11-10 Martin Bojowald , Kevin Vandersloot

We investigate the quantum cosmological tunneling scenario for inflationary models. Within a path-integral approach, we derive the corresponding tunneling probability distribution. A sharp peak in this distribution can be interpreted as the…

广义相对论与量子宇宙学 · 物理学 2014-10-15 Gianluca Calcagni , Claus Kiefer , Christian F. Steinwachs

We contrast the possibility of inflation starting a) from the universe's inception or b) from an earlier non-inflationary state. Neither case is ideal since a) assumes quantum mechanical reasoning is straightforwardly applicable to the…

广义相对论与量子宇宙学 · 物理学 2009-10-31 D. H. Coule

We discuss how initial conditions for cosmological evolution can be defined in Loop Quantum Cosmology with massive scalar field and how the presence of the bounce influences the probability of inflation in this theory, compared with General…

广义相对论与量子宇宙学 · 物理学 2019-02-15 Suzana Bedić , Gregory Vereshchagin

In this paper we consider realistic model of inflation embedded in the framework of loop quantum cosmology. Phase of inflation is preceded here by the phase of a quantum bounce. We show how parameters of inflation depend on the initial…

广义相对论与量子宇宙学 · 物理学 2010-04-06 Jakub Mielczarek

Inflationary cosmology attempts to provide a natural explanation for the flatness and homogeneity of the observable universe. In the context of reversible (unitary) evolution, this goal is difficult to satisfy, as Liouville's theorem…

高能物理 - 理论 · 物理学 2010-07-09 Sean M. Carroll , Heywood Tam

The primordial Universe can be used as a laboratory to set constraints on quantum gravity. In the framework of Loop Quantum Cosmology, we show that such a proposal for quantum gravity not only solves for the big bang singularity issue but…

广义相对论与量子宇宙学 · 物理学 2012-06-08 Julien Grain

We give a detailed presentation of a recently proposed mechanism of generating the energy scale of inflation by loop effects in quantum cosmology. We discuss the quantum origin of the early inflationary Universe from the no-boundary and…

广义相对论与量子宇宙学 · 物理学 2011-08-17 A. O. Barvinsky , A. Yu. Kamenshchik , I. V. Mishakov

A brief review of the modern state of quantum cosmology is presented as a theory of quantum initial conditions for inflationary scenario. The no-boundary and tunneling states of the Universe are discussed as a possible source of probability…

广义相对论与量子宇宙学 · 物理学 2017-08-23 A. O. Barvinsky

An anthropic understanding of the cosmological constant requires that the vacuum energy at late time scans from one patch of the universe to another. If the vacuum energy during inflation also scans, the various patches of the universe…

高能物理 - 理论 · 物理学 2014-11-18 Brian Feldstein , Lawrence J. Hall , Taizan Watari

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…

高能物理 - 理论 · 物理学 2018-06-05 Seoktae Koh , Jung Hun Lee , Chanyong Park , Daeho Ro

This review article aims at presenting the theory of inflation. We first describe the background spacetime behavior during the slow-roll phase and analyze how inflation ends and the Universe reheats. Then, we present the theory of…

高能物理 - 理论 · 物理学 2009-11-10 Jerome Martin

A self-consistent pre-inflationary extension of the inflationary scenario with the Starobinsky potential, favored by Planck data, is studied using techniques from loop quantum cosmology (LQC). The results are compared with the quadratic…

广义相对论与量子宇宙学 · 物理学 2016-05-25 Béatrice Bonga , Brajesh Gupt

This thesis is dedicated to studying cosmological inflation, which is a period of accelerated expansion in the very early Universe that is required to explain the observed anisotropies in the cosmic microwave background. Inflation, when…

宇宙学与河外天体物理 · 物理学 2021-02-02 Chris Pattison

The horizon problem in the standard model of cosmology (LDCM) arises from the observed uniformity of the cosmic microwave background radiation, which has the same temperature everywhere (except for tiny, stochastic fluctuations), even in…

宇宙学与河外天体物理 · 物理学 2018-09-26 Fulvio Melia