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Related papers: Knot Universes in Bianchi Type I Cosmology

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The nature of cosmological solutions for a homogeneous, anisotropic Universe given by a Bianchi type-I (BI) model in the presence of a Cosmological constant $\Lambda$ is investigated by taking into account dissipative process due to…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Bijan Saha , V. Rikhvitsky

We examine solutions to the classical IKKT matrix model equations in three space-time dimensions. Closed, open and static two-dimensional universes naturally emerge from such models in the commutative limit. We show that tachyonic modes are…

High Energy Physics - Theory · Physics 2014-12-24 A. Stern

We present a new method to produce simple formulas for 1-cocycles of knots over the integers, inspired by Polyak-Viro's formulas for finite-type knot invariants. We conjecture that these formulas always represent finite-type cohomology…

Geometric Topology · Mathematics 2015-09-16 Arnaud Mortier

We consider a simple cosmological model consisting of an empty Bianchi I Universe, whose Hamiltonian we deparametrise to provide a natural clock variable. The model thus effectively describes an isotropic universe with an induced clock…

General Relativity and Quantum Cosmology · Physics 2022-01-26 Przemysław Małkiewicz , Patrick Peter , S. D. P. Vitenti

Is the universe finite or infinite, and what shape does it have? These fundamental questions, of which relatively little is known, are typically studied within the context of the standard model of cosmology where the universe is assumed to…

General Relativity and Quantum Cosmology · Physics 2022-06-02 Gregory J. Galloway , Marcus A. Khuri , Eric Woolgar

The Bianchi type $\mathrm{VI}_{-1/9}$, $\mathrm{VIII}$ and $\mathrm{IX}$ vacuum models all have 4-dimensional Hubble-normalized state spaces and are expected to have a generic initial oscillatory singularity, but the invariant boundary sets…

General Relativity and Quantum Cosmology · Physics 2025-09-01 Phillipo Lappicy , Claes Uggla

The Bianchi type-I universe filled with dark energy from a wet dark fluid has been considered. A new equation of state for the dark energy component of the universe has been used. It is modeled on the equation of state $p=\gamma (\rho…

General Relativity and Quantum Cosmology · Physics 2014-11-21 T. Singh , R. Chaubey

The quest to understand better the nature of the initial cosmological singularity is with us since the discovery of the expanding universe. Here, we propose several non-flat models, among them the standard cosmological scenario with a…

General Relativity and Quantum Cosmology · Physics 2021-12-28 Andres Felipe Estupinan Salamanca , Sergio Bravo Medina , Marek Nowakowski , Davide Batic

We analyze the dynamics of the Bianchi I model in the presence of stiff matter, an ultrarelativistic component and a small negative cosmological constant. We quantize this model in the framework of the polymer quantum mechanics, in order to…

General Relativity and Quantum Cosmology · Physics 2018-05-16 Giovanni Montani , Andrea Marchi , Riccardo Moriconi

We provide a quantum picture for the emergence of a bouncing cosmology, according to the idea that a semiclassical behavior of the Universe towards the singularity is not available in many relevant Minisuperspace models. In particular, we…

General Relativity and Quantum Cosmology · Physics 2022-09-07 Eleonora Giovannetti , Giovanni Montani

We solve the Ricci-flat equations of extended general relativity to obtain an interesting class of cosmological models. The solutions are analogous to the 4D ones of Bianchi type-I of Kasner type and have significant implications for…

General Relativity and Quantum Cosmology · Physics 2008-12-18 J. Ponce de Leon , P. S. Wesson

In this article we study closed inflationary universe models proposed by Linde in a brane world cosmological context. In this scenario we determine and characterize the existence of a closed universe, in presence of one self-interacting…

High Energy Physics - Theory · Physics 2009-11-10 Sergio del Campo , Ramon Herrera , Joel Saavedra

We compute the Lema{\^i}tre-Hubble diagram for axial Bianchi IX universes with comoving dust. We motivate our choice by defining a {\it minimal} symmetry breaking of the cosmological principle. This criterium admits only two possibilities:…

General Relativity and Quantum Cosmology · Physics 2023-12-19 Galliano Valent , André Tilquin , Thomas Schücker

In this paper, the knotlike cosmic strings in the Riemann-Cartan space-time of the early universe are discussed. It has been revealed that the cosmic strings can just originate from the zero points of the complex scalar quintessence field.…

High Energy Physics - Theory · Physics 2014-11-18 Yi-shi Duan , Xin Liu

In this paper, we discuss the Bianchi type-I cosmological model in the framework of symmetric teleparallel gravity say $f(Q)$ gravity in which the non-metricity term $Q$ is responsible for the gravitational interaction. We consider a…

General Relativity and Quantum Cosmology · Physics 2023-04-05 M. Koussour , S. H. Shekh , M. Govender , M. Bennai

The non-diagonal Bianchi models are studied in the loop framework for their classical and quantum formulation. The expressions of the Ashtekar-Barbero-Immirzi variables and their properties are found to provide a loop quantization of these…

General Relativity and Quantum Cosmology · Physics 2023-06-19 Matteo Bruno , Giovanni Montani

Some cosmological solutions of massive strings are obtained in Bianchi I space-time following the techniques used by Letelier and Stachel. A class of solutions corresponds to string cosmology associated with/without a magnetic field and the…

General Relativity and Quantum Cosmology · Physics 2021-06-16 A. Banerjee , Abhik Kumar Sanyal , S. Chakraborty

We introduce "anamorphic" cosmology, an approach for explaining the smoothness and flatness of the universe on large scales and the generation of a nearly scale-invariant spectrum of adiabatic density perturbations. The defining feature is…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-02 Anna Ijjas , Paul J. Steinhardt

We extend the entanglement bootstrap approach to (3+1)-dimensions. We study knotted excitations of (3+1)-dimensional liquid topological orders and exotic fusion processes of loops. As in previous work in (2+1)-dimensions, we define a…

High Energy Physics - Theory · Physics 2024-02-29 Jin-Long Huang , John McGreevy , Bowen Shi

The "improved dynamics" of loop quantum cosmology is extended to include anisotropies of the Bianchi I model. As in the isotropic case, a massless scalar field serves as a relational time parameter. However, the extension is non-trivial…

General Relativity and Quantum Cosmology · Physics 2010-04-14 Abhay Ashtekar , Edward Wilson-Ewing
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