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Related papers: Hybrid Models in Loop Quantum Cosmology

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The quantum dynamics of the linearly polarized Gowdy T^3 model (compact inhomogeneous universes admitting linearly polarized gravitational waves) is analyzed within Loop Quantum Cosmology by means of an effective dynamics. The analysis,…

General Relativity and Quantum Cosmology · Physics 2014-11-04 David Brizuela , Guillermo A. Mena Marugan , Tomasz Pawlowski

..."but we do not have quantum gravity." This phrase is often used when analysis of a physical problem enters the regime in which quantum gravity effects should be taken into account. In fact, there are several models of the gravitational…

General Relativity and Quantum Cosmology · Physics 2010-12-23 Marcin Domagala , Kristina Giesel , Wojciech Kaminski , Jerzy Lewandowski

We develop a hybrid qubit-qumode framework for simulating quantum electrodynamics in 2+1 dimensions. In this approach, fermionic matter fields are represented by qubits, while U(1) gauge fields are encoded in continuous-variable bosonic…

Quantum Physics · Physics 2025-11-27 Victor Ale , Tommaso Rainaldi , Enrique Rico , Felix Ringer , George Siopsis

Aspects of the full theory of loop quantum gravity can be studied in a simpler context by reducing to symmetric models like cosmological ones. This leads to several applications where loop effects play a significant role when one is…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Martin Bojowald

In this paper, we address a foundational challenge in quantum field theory on curved spacetime by developing a consistent framework within loop quantum gravity. We introduce a methodology for defining meaningful superpositions of quantum…

General Relativity and Quantum Cosmology · Physics 2026-02-17 Gaoping Long , Cong Zhang

We introduce a class of states characterized by proposed conditions of homogeneity and isotropy in loop quantum gravity and construct concrete examples given by Bell-network states on a special class of homogeneous graphs. Such states…

General Relativity and Quantum Cosmology · Physics 2023-03-29 Bekir Baytas , Nelson Yokomizo

The goal of this work is to elaborate on new geometric methods of constructing exact and parametric quasiperiodic solutions for anamorphic cosmology models in modified gravity theories, MGTs, and general relativity, GR. There exist…

General Relativity and Quantum Cosmology · Physics 2017-10-24 Marcelo M. Amaral , Raymond Aschheim , Laurenţiu Bubuianu , Klee Irwin , Sergiu I. Vacaru , Daniel Woolridge

Since there are quantization ambiguities in constructing the Hamiltonian constraint operator in isotropic loop quantum cosmology, it is crucial to check whether the key features of loop quantum cosmology, such as the quantum bounce and…

General Relativity and Quantum Cosmology · Physics 2009-04-28 Jinsong Yang , You Ding , Yongge Ma

After short historical overview we describe the difficulties with application of standard QFT methods in quantum gravity (QG). The incompatibility of QG with the use of classical continuous space-time required conceptually new approach. We…

High Energy Physics - Theory · Physics 2014-12-01 Jerzy Lukierski

The paradigmatic models often used to highlight cosmological features of loop quantum gravity and group field theory are shown to be equivalent, in the sense that they are different realizations of the same model given by harmonic…

General Relativity and Quantum Cosmology · Physics 2019-05-29 Bekir Baytas , Martin Bojowald , Sean Crowe

Loop quantum gravity in its Hamiltonian form relies on a connection formulation of the gravitational phase space with three key properties: 1.) a compact gauge group, 2.) real variables, and 3.) canonical Poisson brackets. In conjunction,…

General Relativity and Quantum Cosmology · Physics 2024-12-09 Norbert Bodendorfer , Konstantin Eder , Xiangdong Zhang

The alternative dynamics of loop quantum cosmology is examined by the path integral formulation. We consider the spatially flat FRW models with a massless scalar field, where the alternative quantization inherit more features from full loop…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Li Qin , Guo Deng , Yongge Ma

In a paper of Ashtekar and Campiglia, residual diffeomorphisms have been used to single out the standard representation of the reduced holonomy-flux algebra in homogeneous loop quantum cosmology (LQC). We show that, in the homogeneous…

Mathematical Physics · Physics 2015-10-01 Maximilian Hanusch

This introductory review is addressed to beginning researchers. Some of the distinguishing features of loop quantum gravity are illustrated through loop quantum cosmology of FRW models. In particular, these examples illustrate: i) how…

General Relativity and Quantum Cosmology · Physics 2010-11-11 Abhay Ashtekar

An overview of some recent developments in inhomogeneous models is presented. As the volume and precision of cosmological data improves, it will become more and more essential to understand the non-linear behaviour of the Einstein field…

General Relativity and Quantum Cosmology · Physics 2010-01-06 Charles Hellaby

The Horizon Quantum Mechanics is an approach that allows one to analyse the gravitational radius of spherically symmetric systems and compute the probability that a given quantum state is a black hole. We first review the (global) formalism…

General Relativity and Quantum Cosmology · Physics 2018-05-09 Roberto Casadio , Andrea Giugno , Andrea Giusti , Octavian Micu

We introduce a class of hybrid quantum circuits, with random unitaries and projective measurements, which host long-range order in the area law entanglement phase of the steady state. Our primary example is circuits with unitaries…

Statistical Mechanics · Physics 2021-06-22 Shengqi Sang , Timothy H. Hsieh

It has been suggested that the homogeneous black hole interior spacetime, when quantized following the techniques of loop quantum cosmology, has a resolved singularity replaced by a black-to-white hole transition. This result has however…

General Relativity and Quantum Cosmology · Physics 2021-03-23 Francesco Sartini , Marc Geiller

In a metric variable based Hamiltonian quantization, we give a prescription for constructing semiclassical matter-geometry states for homogeneous and isotropic cosmological models. These "collective" states arise as infinite linear…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Viqar Husain , Oliver Winkler

We present a hybrid model of the unitary-evolution-based quantum computation model and the measurement-based quantum computation model. In the hybrid model part of a quantum circuit is simulated by unitary evolution and the rest by…

Quantum Physics · Physics 2011-05-19 Arun Sehrawat , Daniel Zemann , Berthold-Georg Englert