English
Related papers

Related papers: The high-density regime of kinetic-dominated loop …

200 papers

The present work deals with the dynamical system investigation of interacting dark energy models (quintessence and phantom) in the framework of Loop Quantum Cosmology by taking into account a broad class of self-interacting scalar field…

General Relativity and Quantum Cosmology · Physics 2017-11-01 Hmar Zonunmawia , Wompherdeiki Khyllep , Nandan Roy , Jibitesh Dutta , Nicola Tamanini

The resonant state of the open quantum system is studied from the viewpoint of the outgoing momentum flux. We show that the number of particles is conserved for a resonant state, if we use an expanding volume of integration in order to take…

Quantum Physics · Physics 2016-09-08 Naomichi Hatano , Keita Sasada , Hiroaki Nakamura , Tomio Petrosky

We derive stochastic master equations for a quantum system interacting with a Bose field prepared in a superposition of continuous-mode coherent states. To determine a conditional evolution of the quantum system we use a collision model…

Quantum Physics · Physics 2020-02-11 Anita Dabrowska

A model of phantom scalar field dark energy under exponential potential coupling to barotropic dark matter fluid in loop quantum cosmology is addressed here. We derive a closed-autonomous system for cosmological dynamics in this scenario.…

General Relativity and Quantum Cosmology · Physics 2008-04-18 Burin Gumjudpai

We study the dynamics of a bipartite quantum system in a way such that its formal description keeps holding even if one of its parts becomes macroscopic: the problem is related with the analysis of the quantum-to-classical crossover, but…

Quantum Physics · Physics 2017-01-04 Caterina Foti , Alessandro Cuccoli , Paola Verrucchi

The global dynamics of a homogeneous universe in Loop Quantum Cosmology is viewed as a scattering process of its geometrodynamical equivalent. This picture is applied to build a flexible (easy to generalize) and not restricted just to…

General Relativity and Quantum Cosmology · Physics 2010-04-22 Wojciech Kaminski , Tomasz Pawlowski

As an alternative to the paradigm of slow roll inflation, we propose an extended scenario of the matter bounce cosmology in which the Universe has experienced a quasi-matter contracting phase with a variable background equation of state…

General Relativity and Quantum Cosmology · Physics 2015-09-04 Jaume de Haro , Yi-Fu Cai

We compute second-order quantum corrections, as quantum dispersions and correlations, to a cosmological model coupling a single scalar perturbation mode to a bouncing background within Loop Quantum Cosmology (LQC). Using an effective…

General Relativity and Quantum Cosmology · Physics 2026-05-19 Héctor Hernández Hernández , Hugo Morales Técotl , Gustavo Sánchez Herrera

For general number of spatial dimensions we investigate the cosmological dynamics driven by a cosmological constant and by a source with barotropic equation of state. It is assumed that for both those sources the energy density can be…

General Relativity and Quantum Cosmology · Physics 2022-11-09 A. A. Saharian , R. M. Avagyan , E. R. Bezerra de Mello , V. Kh. Kotanjyan , T. A. Petrosyan , H. G. Babujyan

This paper studies the energy decoherence of an interacting quantum system. It first reviews the experiments that motivated the postulates of quantum mechanics. It then discusses a decoherence that occurs dynamically in a closed system.…

Quantum Physics · Physics 2024-12-03 Henry Crumley

We present a review on basic aspects of quantum cosmology in the presence of cut-off physics. We first analyze how the Wheeler-DeWitt equation in a pure metric approach describes the quantum Universe, showing how the singularity is not…

General Relativity and Quantum Cosmology · Physics 2021-09-20 Gabriele Barca , Eleonora Giovannetti , Giovanni Montani

We perform a detailed investigation of the simplest possible cosmological model in which a bounce can occur, namely that where the dynamics is led by a simple massive scalar field in a general self-interacting potential and a background…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Felipe T. Falciano , Marc Lilley , Patrick Peter

We study the behavior of an open quantum system, with an $N$--dimensional space of states, whose density matrix evolves according to a non--unitary map defined in two steps: A unitary step, where the system evolves with an evolution…

Quantum Physics · Physics 2009-11-07 Pablo Bianucci , Juan Pablo Paz , Marcos Saraceno

Simple states, such as isobaric analog states or giant resonances, embedded into continuum are typical for mesoscopic many-body quantum systems. Due to the coupling to compound states in the same energy range, a simple mode acquires a…

Nuclear Theory · Physics 2016-09-08 V. V. Sokolov , V. G. Zelevinsky

A union of matter bounce and Ekpyrotic scenarios is often studied in an attempt to combine the most promising features of these two models. Since non-perturbative quantum geometric effects in loop quantum cosmology (LQC) result in natural…

General Relativity and Quantum Cosmology · Physics 2021-03-31 Bao-Fei Li , Sahil Saini , Parampreet Singh

The rate of the trace distance is used to evaluate quantum speed-up for arbitrary mixed states. Compared with some present methods, the approach based on trace distance can provide an optimal bound to the speed of the evolution. The…

Quantum Physics · Physics 2016-11-04 Xiang Hao , Wenjiong Wu

Although quintessence cosmologies seem to explain the amount of cosmological constant today, the required conditions are severe. For example, an extremely slowly varying and light scalar field that rolls toward the vanishing vacuum energy…

High Energy Physics - Phenomenology · Physics 2007-05-23 Tomohiro Matsuda

The recent transition from decelerated to accelerated expansion can be seen as a reflection (or "bounce") in the connection variable, defined by the inverse comoving Hubble length ($b=\dot a$, on-shell). We study the quantum cosmology of…

General Relativity and Quantum Cosmology · Physics 2022-10-06 Bruno Alexandre , Joao Magueijo

We present the method of describing an evolution in quantum cosmology in the framework of the reduced phase space quantization of loop cosmology. We apply our method to the flat Friedman-Robertson-Walker model coupled to a massless scalar…

General Relativity and Quantum Cosmology · Physics 2012-03-06 Jakub Mielczarek , Wlodzimierz Piechocki

We study the dynamics of the Bianchi I universe in modified loop quantum cosmology (mLQC-I) and uncover a robust mechanism for isotropization: the shear is dynamically suppressed after the bounce and decays rapidly in the quantum…

General Relativity and Quantum Cosmology · Physics 2026-05-26 Wen-Cong Gan , Leila L. Graef , Rudnei O. Ramos , Gustavo S. Vicente , Anzhong Wang