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Related papers: Four-mode squeezed states in de Sitter space: A st…

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We analyze the quantum walk on a cycle using discrete Wigner functions as a way to represent the states and the evolution of the walker. The method provides some insight on the nature of the interference effects that make quantum and…

Quantum Physics · Physics 2009-11-10 C. C. Lopez , J. P. Paz

Multifield models with a curved field space have already been shown to be able to provide viable quintessence models for steep potentials that satisfy swampland bounds. The simplest dynamical systems of this type are obtained by coupling…

High Energy Physics - Theory · Physics 2020-10-28 Michele Cicoli , Giuseppe Dibitetto , Francisco G. Pedro

The position variance of a single-mode Yuen states can go below the standard quantum limit. For two-mode squeezed states, it is shown that the time-dependent evolution of the entanglement of formation can be contractive, going below that of…

Quantum Physics · Physics 2007-05-23 R. W. Rendell , A. K. Rajagopal

We construct semiclassical solutions of the symplectically covariant Schroedinger phase-space equation rigorously studied in a previous paper; we use for this purpose an adaptation of Littlejohn's nearby-orbit method. We take the…

Quantum Physics · Physics 2007-05-23 Maurice de Gosson , Serge de Gosson

The generated magnitude of quadrature squeezing in a cavity-coupled ensemble, which is continuously driven using a coherent off-axis field, is theoretically explored. Using a truncated set of equations-of-motion derived from a Dicke…

Quantum Physics · Physics 2021-02-05 Haitham A. R. El-Ella

The Euclidean or Bunch-Davies O(4,1) invariant 'vacuum' state of quantum fields in global de Sitter space is shown to be unstable to small perturbations, even for a massive free field with no self-interactions. There are perturbations of…

General Relativity and Quantum Cosmology · Physics 2014-05-28 Paul R. Anderson , Emil Mottola

In this thesis, I go through the well-known solutions to the one and two-particle systems trapped in a quantum harmonic oscillator and then continue to the three, four and many-body quantum systems. This is done by developing new analytical…

Quantum Gases · Physics 2018-01-17 A. S. Dehkharghani

(1+1)-dimensional locally de Sitter Friedmann-Robertson-Walker cosmologies with compact spatial sections allow cosh, sinh and exponential evolution laws, each with a freely-specifiable spatial circumference parameter, and the value of this…

General Relativity and Quantum Cosmology · Physics 2024-01-19 Vladimir Toussaint , Jorma Louko

We apply the squeezed state formalism to scalar field dark matter (e.g. axion) perturbations generated during inflation. As for the inflationary perturbations, the scalar field state becomes highly squeezed as modes exit the horizon. For as…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-29 Jondalar L. J. Kuß , David J. E. Marsh

The primary aim of the present paper is to attract the attention of particle physicists to new developments in studying squeezed and correlated states of the electromagnetic field as well as of those working on the latest topic to new…

High Energy Physics - Phenomenology · Physics 2019-08-17 V. V. Dodonov , I. M. Dremin , O. V. Man'ko , V. I. Man'ko , P. G. Polynkin

A quantum mechanical formulation of de Sitter cosmological spacetimes still eludes string theory. In this paper we conjecture a potentially rigorous framework in which the status of de Sitter space is the same as that of a resonance in a…

High Energy Physics - Theory · Physics 2017-03-15 Jonathan Maltz , Leonard Susskind

Understanding the mechanism through which an open quantum system exchanges information with an environment is central to the creation and stabilization of quantum states. This theme has been explored recently, with attention mostly focused…

Quantum Physics · Physics 2023-02-22 R. Gutiérrez-Jáuregui , A. Asenjo-Garcia , G. S. Agarwal

We propose precise effective field theory criteria to obtain a four-dimensional de Sitter space within M-theory. To this effect, starting with the state space described by the action of metric perturbations, fluxes etc over the…

High Energy Physics - Theory · Physics 2024-10-25 Joydeep Chakravarty , Keshav Dasgupta

We study entanglement concentration of continuous variable Gaussian states by local photon subtractions enhanced by coherent displacements. Instead of the previously considered symmetric two-mode squeezed vacuum states, we investigate the…

Quantum Physics · Physics 2012-12-06 Ondřej Černotík , Jaromír Fiurášek

Spins in solids and molecules are promising for applications of quantum sensing technology. The sensitivity of the quantum sensing depends on how precisely spin observables can be determined in the measurement, and is intrinsically limited…

Quantum Physics · Physics 2025-11-21 Yifan Song , Nabiha Hasan , Susumu Takahashi

We investigate the cosmological dynamics of non-minimally coupled scalar field system described by $F(\phi)R$ coupling with $F(\phi)=(1-\xi\phi^N)R$($N\ge2$) and the field potential, $V(\phi)=V_0\phi^n$. We use a generic set of dynamical…

High Energy Physics - Theory · Physics 2013-05-30 M. Sami , M. Shahalam , M. Skugoreva , A. Toporensky

In this thesis, we aim to understand the microscopic details and origin of the Cosmological Horizon, produced by a static observer in four-dimensional de Sitter (dS$_4$) spacetime. We consider a deformed extension of dS spacetime by means…

High Energy Physics - Theory · Physics 2019-12-24 Felipe Diaz

We present a quantum Monte-Carlo simulation for a pumped atom in a strong coupling cavity with dissipation, where two ordered spatial modes are formed for the atomic probability density, with the peaks distributed either only in the odd…

Quantum Physics · Physics 2015-06-16 Zhen Fang , Baoguo Yang , Xuzong Chen , Xiaoji Zhou

The dynamics of the Brans-Dicke theory with a quadratic scalar field potential function and barotropic matter is investigated. The dynamical system methods are used to reveal complexity of dynamical evolution in homogeneous and isotropic…

General Relativity and Quantum Cosmology · Physics 2013-12-11 Orest Hrycyna , Marek Szydlowski

We study QED$_2$ in de Sitter space as a minimal interacting gauge theory in which cosmological expansion directly competes with quantum dynamics. In cosmic time, the hopping redshifts as $1/a(t)$ while the electric term grows as $g^2…

High Energy Physics - Theory · Physics 2026-04-06 Kazuki Ikeda , Yaron Oz