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

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The probability of there being sufficient inflation to solve the fine-tuning associated with the horizon and flatness problems has recently been shown to be exponentially small, within the context of classical general relativity. Here this…

广义相对论与量子宇宙学 · 物理学 2007-08-27 William Nelson

Using a Liouville measure, similar to the one proposed recently by Gibbons and Turok, we investigate the probability that single-field inflation with a polynomial potential can last long enough to solve the shortcomings of the standard hot…

广义相对论与量子宇宙学 · 物理学 2008-11-26 Cristiano Germani , William Nelson , Mairi Sakellariadou

On the one hand, inflation is an extremely convincing scenario: it solves most cosmological paradoxes and generates fluctuations that became the seeds for the growth of structures. It, however, suffers from a "naturalness" problem:…

广义相对论与量子宇宙学 · 物理学 2011-08-04 Aurelien Barrau

Inflationary models of the early universe provide a natural mechanism for the formation of large scale structure. This success brings to forefront the question of naturalness: Does a sufficiently long slow roll inflation occur generically…

广义相对论与量子宇宙学 · 物理学 2015-05-27 Abhay Ashtekar , David Sloan

Warm inflation is analyzed in the context of Loop Quantum Cosmology (LQC). The bounce in LQC provides a mean through which a Liouville measure can be defined, which has been used previously to characterize the a priori probability for…

广义相对论与量子宇宙学 · 物理学 2018-08-01 L. L. Graef , Rudnei O. Ramos

The standard model of cosmology assumes a homogeneous and isotropic universe that undergoes a period of exponential expansion very early on, named inflation. This stretches quantum fluctuations from the onset of inflation to cosmological…

广义相对论与量子宇宙学 · 物理学 2024-10-22 Rita B. Neves

In loop quantum gravity, modifications to the geometrical density cause a self-interacting scalar field to accelerate away from a minimum of its potential. In principle, this mechanism can generate the conditions that subsequently lead to…

广义相对论与量子宇宙学 · 物理学 2009-11-10 Martin Bojowald , James E. Lidsey , David J. Mulryne , Parampreet Singh , Reza Tavakol

We investigate uniform rate inflationary universe in the framework of loop quantum cosmology (LQC) and find that this seemingly simple inflationary model is interlinked with various concepts such as cyclic evolution, HNI inflation and…

广义相对论与量子宇宙学 · 物理学 2025-12-24 Bikash Chandra Paul , Sahil Saini

Loop quantum cosmology provides an efficient framework to study the evolution of the Universe beyond the classical Big Bang paradigm. Because of holonomy corrections, the singularity is replaced by a "bounce". The dynamics of the background…

广义相对论与量子宇宙学 · 物理学 2015-03-13 Jakub Mielczarek , Thomas Cailleteau , Julien Grain , Aurelien Barrau

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…

广义相对论与量子宇宙学 · 物理学 2015-07-21 Gianluca Calcagni , Claus Kiefer , Christian F. Steinwachs

In a previous paper we proposed a new approach to the beginning of inflation -- a lingering universe. The universe begins in a lingering state with a nearly vanishing Hubble parameter. This calls into question the absolute age of the…

宇宙学与河外天体物理 · 物理学 2025-01-09 Brandon Melcher , Arnab Pradhan , Scott Watson

We consider the measure problem in standard slow-roll inflationary models from the perspective of loop quantum cosmology (LQC). Following recent results by Ashtekar and Sloan, we study the probability of having enough e-foldings and focus…

广义相对论与量子宇宙学 · 物理学 2011-05-12 Alejandro Corichi , Asieh Karami

At the level of heuristic effective dynamics, we investigate the cosmological inflation with holonomy corrections of loop quantum cosmology (LQC) in the $k=0$ Friedmann-Robertson-Walker model with a single inflaton field subject to a simple…

广义相对论与量子宇宙学 · 物理学 2010-04-29 Dah-Wei Chiou , Kai Liu

We investigate how various inflationary and bouncing cosmologies can be realized by imperfect fluids with a generalized equation of state, in the context of both classical and loop quantum cosmology. With regards to the inflationary…

广义相对论与量子宇宙学 · 物理学 2017-09-06 V. K. Oikonomou

Loop Quantum Gravity (L.Q.G.) is one of the two most promising tentative theory for a quantum description of gravity. When applied to the entire universe, the so-called Loop Quantum Cosmology (L.Q.C.) framework offers microscopical models…

广义相对论与量子宇宙学 · 物理学 2014-11-20 J. Grain

In loop quantum cosmology there may be a super-inflation phase in the very early universe, in which a single scalar field with a negative power-law potential $V= -M^4(\phi/M)^\beta$ plays important roles. Since the effective horizon…

广义相对论与量子宇宙学 · 物理学 2009-11-19 Masahiro Shimano , Tomohiro Harada

Inflation creates large-scale cosmological density perturbations that are characterized by an isotropic, homogeneous, and Gaussian random distribution about a locally flat background. Even in a flat universe, the spatial curvature measured…

宇宙学与河外天体物理 · 物理学 2015-06-04 Matthew Kleban , Marjorie Schillo

Phenomenological effect of the super-inflation in loop quantum cosmology (LQC) is discussed. We investigate the case that the Universe is filled with the interacting field between massive scalar field and radiation. Considering the damping…

广义相对论与量子宇宙学 · 物理学 2013-11-28 Kui Xiao , Xiao-Kai He , Jian-Yang Zhu

It is proposed that if quantum states of space-time are coherent on null surfaces, holographic Planck-scale fluctuations of inflationary horizons dominate the formation of primordial scalar curvature perturbations. It is shown that the…

宇宙学与河外天体物理 · 物理学 2020-06-17 Craig Hogan

We study how the initial inhomogeneities of the spatial curvature affect the onset of inflation in the closed universe. We consider a cosmological model which contains a radiation and a cosmological constant. In order to treat the…

广义相对论与量子宇宙学 · 物理学 2011-07-19 O. Iguchi , H. Ishihara , J. Soda
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