English
Related papers

Related papers: Quantum Nature of the Big Bang

200 papers

Analytical and numerical methods are developed to analyze the quantum nature of the big bang in the setting of loop quantum cosmology. They enable one to explore the effects of quantum geometry both on the gravitational and matter sectors…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Abhay Ashtekar , Tomasz Pawlowski , Parampreet Singh

An improved Hamiltonian constraint operator is introduced in loop quantum cosmology. Quantum dynamics of the spatially flat, isotropic model with a massless scalar field is then studied in detail using analytical and numerical methods. The…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Abhay Ashtekar , Tomasz Pawlowski , Parampreet Singh

We discuss the way non-perturbative quantization of cosmological spacetimes in loop quantum cosmology provides insights on the physics of Planck scale and the resolution of big bang singularity. In recent years, rigorous examination of…

General Relativity and Quantum Cosmology · Physics 2009-03-27 Parampreet Singh

Several examples are known where quantum gravity effects resolve the classical big bang singularity by a bounce. The most detailed analysis has probably occurred for loop quantum cosmology of isotropic models sourced by a free, massless…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Martin Bojowald

Loop quantum cosmology homogeneous models with a massless scalar field show that the big-bang singularity can be replaced by a big quantum bounce. To gain further insight on the nature of this bounce, we study the semi-discrete loop quantum…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Pablo Laguna

We study the polymeric nature of quantum matter fields using the example of a Friedmann-Lemaitre-Robertson-Walker universe sourced by a minimally coupled massless scalar field. The model is treated in the symmetry reduced regime via…

General Relativity and Quantum Cosmology · Physics 2015-09-16 Andreas Kreienbuehl , Tomasz Pawlowski

Isotropic models in loop quantum cosmology allow explicit calculations, thanks largely to a completely known volume spectrum, which is exploited in order to write down the evolution equation in a discrete internal time. Because of genuinely…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Martin Bojowald

The exactly solvable quantum model of the homogeneous, isotropic and closed universe in the matter-energy production epoch is considered. It is assumed that the universe is originally filled with a uniform scalar field and a perfect fluid…

General Relativity and Quantum Cosmology · Physics 2011-07-19 V. E. Kuzmichev , V. V. Kuzmichev

When quantum gravity is used to discuss the big bang singularity, the most important, though rarely addressed, question is what role genuine quantum degrees of freedom play. Here, complete effective equations are derived for isotropic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald

The closed, k=1, FRW model coupled to a massless scalar field is investigated in the framework of loop quantum cosmology using analytical and numerical methods. As in the k=0 case, the scalar field can be again used as emergent time to…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Abhay Ashtekar , Tomasz Pawlowski , Parampreet Singh , Kevin Vandersloot

We investigate the emergence of a quantum Big-Bounce in the context of an isotropic Universe, filled by a self-interacting scalar field, which plays the role of a physical clock. The bouncing cosmology is the result of a scattering process,…

General Relativity and Quantum Cosmology · Physics 2024-10-04 S. Lo Franco , G. Montani

Quantum effects are expected to modify the cosmological dynamics of the early universe while maintaining some (potentially discrete) notion of space-time structure. In one approach, loop quantum cosmology, current models are shown here to…

General Relativity and Quantum Cosmology · Physics 2026-04-29 Martin Bojowald , Manuel Diaz , Erick I. Duque

The quantum nature of the Big Bang is reexamined in the framework of Loop Quantum Cosmology. The strict application of a regularization procedure to the Hamiltonian, originally developed for the Hamiltonian in loop quantum gravity, leads to…

General Relativity and Quantum Cosmology · Physics 2018-08-29 Mehdi Assanioussi , Andrea Dapor , Klaus Liegener , Tomasz Pawłowski

A simple model for a scalar field and gravity admits homogeneous isotropic cosmological solutions which cross the Big Bang singularity. In the scaling frame with field dependent effective Planck mass these solutions are regular. They become…

General Relativity and Quantum Cosmology · Physics 2021-07-27 C. Wetterich

The absence of isotropic singularity in loop quantum cosmology can be understood in an effective classical description as the universe exhibiting a Big Bounce. We show that with scalar matter field, the big bounce is generic in the sense…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Ghanashyam Date , Golam Mortuza Hossain

It is shown that the cosmological singularity in isotropic minisuperspaces is naturally removed by quantum geometry. Already at the kinematical level, this is indicated by the fact that the inverse scale factor is represented by a bounded…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald

Singularities in general relativity such as the big bang and big crunch, and exotic singularities such as the big rip are the boundaries of the classical spacetimes. These events are marked by a divergence in the curvature invariants and…

General Relativity and Quantum Cosmology · Physics 2015-10-01 Parampreet Singh

The comprehensive formulation for loop quantum cosmology in the spatially flat, isotropic model was recently constructed. In this paper, the methods are extended to the anisotropic Bianchi I cosmology. Both the precursor and the improved…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Dah-Wei Chiou

The initial cosmological singularity in the framework of the general theory of relativity is resolved by introducing the effect of the uncertainty principle of quantum theory without violating conventional laws of physics. A plausible…

Astrophysics · Physics 2009-11-07 D. C. Choudhury

Since the past Iagrg meeting in December 2004, new developments in loop quantum cosmology have taken place, especially with regards to the resolution of the Big Bang singularity in the isotropic models. The singularity resolution issue has…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ghanashyam Date
‹ Prev 1 2 3 10 Next ›