English
Related papers

Related papers: Generalised DBI-Quintessence

200 papers

We consider a gas of ultracold two-level atoms confined in a cavity, taking into account for atomic center-of-mass motion and cavity mode variations. We use the generalized Dicke model, and analyze separately the cases of a Gaussian, and a…

Quantum Physics · Physics 2015-05-13 Jonas Larson , Maciej Lewenstein

We consider a class of generalised single mode Dicke Hamiltonians with arbitrary boson coupling in the pseudo-spin $x$-$z$ plane. We find exact solutions in the thermodynamic, large-spin limit as a function of the coupling angle, which…

Quantum Physics · Physics 2009-11-10 Clive Emary , Tobias Brandes

Quantum devices are preparing increasingly more complex entangled quantum states. How can one effectively study these states in light of their increasing dimensions? Phase spaces such as Wigner functions provide a suitable framework. We…

Quantum Physics · Physics 2021-01-04 Bálint Koczor , Robert Zeier , Steffen J. Glaser

We further elaborate on a phase-space picture for a system of $N$ qubits and explore the structures compatible with the notion of unbiasedness. These consist of bundles of discrete curves satisfying certain additional properties and…

Quantum Physics · Physics 2017-06-14 C. Munoz , A. B. Klimov , L. L. Sanchez-Soto

We present an alternative formalism of quantum mechanics tailored to statistical ensemble in phase space. The purpose of our work is to show that it is possible to establish an alternative autonomous formalism of quantum mechanics in phase…

Quantum Physics · Physics 2018-11-20 Chol Jong , Byong-Il Ri , Song-Guk Kim , Son-Il Jo , Shin-Hyok Jon , Namchol Choe

Density functional theory (DFT) is shown to provide a novel conceptual and computational framework for entanglement in interacting many-body quantum systems. DFT can, in particular, shed light on the intriguing relationship between quantum…

Quantum Physics · Physics 2009-11-11 L. -A. Wu , M. S. Sarandy , D. A. Lidar , L. J. Sham

Starting from the balance equations of mass, momentum and energy we formulate an integral 1D model for a poly-disperse mixture injected in the atmosphere. We write all the equations, either in their most general formulation or in the more…

Geophysics · Physics 2015-09-15 Matteo Cerminara

The purpose of this paper is twofold: On the one hand, after a thorough review of the matter free case, we supplement the derivations in our companion paper on 'loop quantum gravity without the Hamiltonian constraint' with calculational…

General Relativity and Quantum Cosmology · Physics 2013-05-14 Norbert Bodendorfer , Alexander Stottmeister , Andreas Thurn

Recent observations seem to suggest that our Universe is accelerating implying that it is dominated by a fluid whose equation of state is negative. Quintessence is a possible explanation. In particular, the concept of tracking solutions…

Astrophysics · Physics 2009-10-31 Philippe Brax , Jerome Martin

Dynamical phase transitions (DPTs) are signaled by the non-analytical time evolution of the dynamical free energy after quenching some global parameters in quantum systems. The dynamical free energy is calculated from the overlap between…

Statistical Mechanics · Physics 2019-03-04 R. Jafari

The RG flow equation of various transport quantities are studied in arbitrary spacetime dimensions, in the fixed as well as fluctuating background geometry both for the Maxwellian and DBI type of actions. The regularity condition on the…

High Energy Physics - Theory · Physics 2015-05-30 Bum-Hoon Lee , Shesansu Sekhar Pal , Sang-Jin Sin

Some dark energy cosmological models are constructed in the framework of a generalised Brans-Dicke theory which contains a self interacting potential and a dynamical coupling parameter. The dark sector of the universe is considered through…

General Relativity and Quantum Cosmology · Physics 2022-07-19 S. K. Tripathy , Sasmita K Pradhan , Z. Naik , D. Behera , B. Mishra

In this paper we present the cosmological dynamics of a perfect fluid and the Dark Energy (DE) component of the Universe, where our model of the dark energy is the string-theoritic Dirac-Born-Infeld (DBI) model. We assume that the potential…

General Relativity and Quantum Cosmology · Physics 2021-03-05 Subhajyoti Pal , Subenoy Chakraborty

The structure of the dark energy equation of state phase plane holds important information on the nature of the physics. We explain the bounds of the freezing and thawing models of scalar field dark energy in terms of the tension between…

Astrophysics · Physics 2009-11-11 Eric V. Linder

With the tracking condition, the stability of quintessence solutions are examined. It is found that there is only one physically relevant fixed point for the system generically. Two specific examples of quintessence potentials are worked…

General Relativity and Quantum Cosmology · Physics 2013-12-11 Nandan Roy , narayan Banerjee

We present an innovative approach to dimensional analysis, based on a general representation theorem for complete quantity functions admitting a covariant scalar representation; this theorem is in turn grounded in a purely algebraic theory…

Mathematical Physics · Physics 2020-12-15 Dan Jonsson

The issues of quintessence and cosmic acceleration can be discussed in the framework of theories which do not include necessarily scalar fields. It is possible to define pressure and energy density for new components considering effective…

Astrophysics · Physics 2008-11-26 S. Capozziello , S. Carloni , A. Troisi

An operator generalisation of the notion of geometric phase has been recently proposed purely based on physical grounds. Here we provide a mathematical foundation for its existence, while uncovering new geometrical structures in quantum…

Quantum Physics · Physics 2023-12-25 Vivek M. Vyas

We solve a very general two-channel fermion-boson model describing charge transport within some background medium by means of a refined pseudo-site density matrix renormalization group (DMRG) technique. Performing a careful finite-size…

Strongly Correlated Electrons · Physics 2009-11-13 S. Ejima , G. Hager , H. Fehske

Quantum coherence will undoubtedly play a fundamental role in understanding the dynamics of quantum many-body systems, thereby to reveal its genuine contribution is of great importance. In this paper, we specialize our discussions on the…

Quantum Physics · Physics 2024-10-29 Bao-Ming Xu