English
Related papers

Related papers: Robustness of the quantum BKL scenario

200 papers

Present day quantum field theory (QFT) is founded on canonical quantization, which has served quite well, but also has led to several issues. The free field describing a free particle (with no interaction term) can suddenly become…

General Physics · Physics 2021-08-13 John R. Klauder

We show that when a quantum system is coupled to an environment in a mean field way, then its effective dynamics is governed by a unitary group with a time-dependent Hamiltonian. The time-dependent modification of the bare system…

Quantum Physics · Physics 2024-09-25 Michele Fantechi , Marco Merkli

Quantum many-body systems exhibit an extremely diverse range of phases and physical phenomena. Here, we prove that the entire physics of any other quantum many-body system is replicated in certain simple, "universal" spin-lattice models. We…

Quantum Physics · Physics 2019-10-07 Toby Cubitt , Ashley Montanaro , Stephen Piddock

Contextuality is a fundamental non-classical property of quantum theory, which has recently been proven to be a key resource for achieving quantum speed-ups in some leading models of quantum computation. However, which of the forms of…

Quantum Physics · Physics 2019-04-17 Piers Lillystone , Joel J. Wallman , Joseph Emerson

Characterising unknown quantum states and measurements is a fundamental problem in quantum information processing. In this Letter, we provide a novel scheme to self-test local quantum systems using non-contextuality inequalities. Our work…

We analize the relational quantum evolution of generally covariant systems in terms of Rovelli's evolving constants of motion and the generalized Heisenberg picture. In order to have a well defined evolution, and a consistent quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Rodolfo Gambini , Rafael A. Porto

The article explores challenges presented by revelations in physics and the questions they provoke concerning reality. It sheds light on the disparity between the indefinite nature of quantum reality and our perception of classical reality.…

General Physics · Physics 2024-05-14 Jahan N. Schad

The physics of many closed, conservative systems can be described by both classical and quantum theories. The dynamics according to classical theory is symplectic and admits linear instabilities which would initially seem at odds with a…

Quantum Physics · Physics 2024-01-08 Michael Q. May , Hong Qin

The exact and stable evolutions of generalized coherent states (GCS) for quantum systems are considered by making use of the time-dependent integrals of motion method and of the Klauder approach to the relationship between quantum and…

Quantum Physics · Physics 2007-05-23 B. A. Nikolov , D. A. Trifonov

We observe that a wide class of higher-derivative systems admits a bounded integral of motion that ensures the classical stability of dynamics, while the canonical energy is unbounded. We use the concept of a Lagrange anchor to demonstrate…

High Energy Physics - Theory · Physics 2015-06-22 D. S. Kaparulin , S. L. Lyakhovich , A. A. Sharapov

In the asymptotic safety paradigm, a quantum field theory reaches a regime with quantum scale invariance in the ultraviolet, which is described by an interacting fixed point of the Renormalization Group. Compelling hints for the viability…

General Relativity and Quantum Cosmology · Physics 2018-08-01 Astrid Eichhorn

We explore the concept of emergent quantum-like theory in complex adaptive systems, and examine in particular the concrete example of such an emergent (or "mock") quantum theory in the Lotka-Volterra system. In general, we investigate the…

Quantum Physics · Physics 2025-02-05 Tristan Hubsch , Djordje Minic , Konstantin Nikolic , Sinisa Pajevic

A mechanism describing state reduction dynamics in relativistic quantum field theory is outlined. The mechanism involves nonlinear stochastic modifications to the standard description of unitary state evolution and the introduction of a…

Quantum Physics · Physics 2015-05-18 Daniel J. Bedingham

We consider in general terms dynamical systems with finite-dimensional, non-simply connected configuration-spaces. The fundamental group is assumed to be finite. We analyze in full detail those ambiguities in the quantization procedure that…

Quantum Physics · Physics 2007-05-23 Domenico Giulini

Motivated by studies of typical properties of quantum states in statistical mechanics, we introduce phase-random states, an ensemble of pure states with fixed amplitudes and uniformly distributed phases in a fixed basis. We first show that…

Quantum Physics · Physics 2015-03-19 Yoshifumi Nakata , Peter S. Turner , Mio Murao

General methods of quantitative and qualitative continuity analysis of characteristics of composite quantum systems are described. Several modifications of the Alicki-Fannes-Winter method are considered, which make it applicable to a wide…

Quantum Physics · Physics 2025-02-18 M. E. Shirokov

An affine quantization approach leads to a genuine quantum theory of general relativity by extracting insights from a short list of increasingly more complex, soluble, perturbably nonrenormalizable models.

General Relativity and Quantum Cosmology · Physics 2019-03-27 John R. Klauder

We present the result of our examination of quantum structures called quantum spikes. The classical spikes, that are known in gravitational systems, occur in the evolution of the inhomogeneous spacetimes. Different kind of spikes, which we…

General Relativity and Quantum Cosmology · Physics 2021-03-05 Andrzej Góźdź , Włodzimierz Piechocki , Grzegorz Plewa , Tomasz Trześniewski

We propose a simple test of quantumness which can decide whether for the given set of accessible experimental data the classical model is insufficient. Take two observables $ A,B$ such that for any state $\psi$ their mean values satisfy…

Quantum Physics · Physics 2012-10-26 Robert Alicki , Nicholas Van Ryn

An assessment is given as to the extent to which pure unitary evolution, as distinct from environmental decohering interaction, can provide the transition necessary for an observer to interpret perceived quantum dynamics as classical. This…

Quantum Physics · Physics 2021-10-05 John S. Briggs