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This is the first in a series of papers outlining an algorithm to explicitly construct finite quantum states of the full theory of gravity in Ashtekar variables. The algorithm is based upon extending some properties of a special state, the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Eyo Eyo Ita

We extend the Wigner-Weyl-Moyal phase-space formulation of quantum mechanics to general curved configuration spaces. The underlying phase space is based on the chosen coordinates of the manifold and their canonically conjugate momenta. The…

Quantum Physics · Physics 2023-02-07 Clemens Gneiting , Timo Fischer , Klaus Hornberger

The complexity of the quantum state of a multiparticle system and the maximum possible accuracy of its quantum description are connected by a relation similar to the coordinate-momentum uncertainty relation. The coefficient in this relation…

Quantum Physics · Physics 2021-10-01 Yuri I. Ozhigov

Coherent states can be used for diverse applications in quantum physics including the construction of coherent state path integrals. Most definitions make use of a lattice regularization; however, recent definitions employ a continuous-time…

Quantum Physics · Physics 2007-05-23 John R. Klauder

Recently, there is a growing interest in study quantum mechanics from the information geometry perspective, where a quantum state is depicted with a point in the projective Hilbert space. By taking quantum Fisher information (QFI) as the…

Quantum Physics · Physics 2021-01-04 Haijun Xing , Libin Fu

Weak coherent states share many properties of the usual coherent states, but do not admit a resolution of unity expressed in terms of a local integral. They arise e.g. in the case that a group acts on an inadmissible fiducial vector.…

High Energy Physics - Theory · Physics 2009-11-10 Lorenz Hartmann , John R. Klauder

Classical-quantum computational complexity separations are an important motivation for the long-term development of digital quantum computers, but classical-quantum complexity equivalences are just as important in our present era of noisy…

Quantum Physics · Physics 2020-03-10 Jonathan E. Moussa

Complexity theory traditionally studies the hardness of solving classical computational problems. In the quantum setting, it is also natural to consider a different notion of complexity, namely the complexity of physically preparing a…

Quantum Physics · Physics 2023-04-11 Tony Metger , Henry Yuen

The phase-space formulation of quantum mechanics has recently seen increased use in testing quantum technologies, including metho ds of tomography for state verification and device validation. Here, an overview of quantum mechanics in phase…

Quantum Physics · Physics 2021-04-05 Russell P Rundle , Mark J Everitt

Non-classical states are of practical interest in quantum computing and quantum metrology. These states can be detected through their Wigner function negativity in some regions. In this paper, we calculate the ground state of the…

Quantum Physics · Physics 2021-02-03 Ramón López-Peña , Sergio Cordero , Eduardo Nahmad-Achar , Octavio Castaños

Instantaneous quantum computing is a sub-universal quantum complexity class, whose circuits have proven to be hard to simulate classically in the Discrete-Variable (DV) realm. We extend this proof to the Continuous-Variable (CV) domain by…

Quantum Physics · Physics 2017-02-21 T. Douce , D. Markham , E. Kashefi , E. Diamanti , T. Coudreau , P. Milman , P. van Loock , G. Ferrini

Quantum many-body systems are characterized by patterns of correlations that define highly-non trivial manifolds when interpreted as data structures. Physical properties of phases and phase transitions are typically retrieved via simple…

Statistical Mechanics · Physics 2021-09-01 Tiago Mendes-Santos , Adriano Angelone , Alex Rodriguez , Rosario Fazio , Marcello Dalmonte

We study the density of quasiparticle states of dirty d-wave superconductors. We show the existence of singular corrections to the density of states due to quantum interference effects. We then argue that the density of states actually…

Superconductivity · Physics 2009-10-31 T. Senthil , Matthew P. A. Fisher

There is no unique way to quantify the degree of delocalization of quantum states in unbounded continuous spaces. In this work, we explore a recently introduced localization measure that quantifies the portion of the classical phase space…

We analyze how measured quantum dynamical systems store and process information, introducing sofic quantum dynamical systems. Using recently introduced information-theoretic measures for quantum processes, we quantify their information…

Quantum Physics · Physics 2007-05-23 Karoline Wiesner , James P. Crutchfield

We study continuous variable systems, in which quantum and classical degrees of freedom are combined and treated on the same footing. Thus all systems, including the inputs or outputs to a channel, may be quantum-classical hybrids. This…

Quantum Physics · Physics 2023-07-26 Lars Dammeier , Reinhard F. Werner

The study of conditional $q$-entropies in composite quantum systems has recently been the focus of considerable interest, particularly in connection with the problem of separability. The $q$-entropies depend on the density matrix $\rho$…

Quantum Physics · Physics 2009-11-10 J. Batle , A. R. Plastino , M. Casas , A. Plastino

Quantum process learning is a fundamental primitive that draws inspiration from machine learning with the goal of better studying the dynamics of quantum systems. One approach to quantum process learning is quantum compilation, whereby an…

A general procedure is established to calculate the quantum phase diagrams for finite matter-field Hamiltonian models. The minimum energy surface associated to the different symmetries of the model is calculated as a function of the…

Quantum Physics · Physics 2021-02-03 Sergio Cordero , Eduardo Nahmad-Achar , Ramón López-Peña , Octavio Castaños

Nonequilibrium dynamics of highly-controlled quantum systems is a challenging issue in statistical physics and quantum many-body physics, relevant to recent experimental developments of analog and digital quantum simulations. In this work,…

Quantum Gases · Physics 2025-05-21 Kazuma Nagao , Seiji Yunoki