English
Related papers

Related papers: A note on the formal structure of quantum constrai…

200 papers

We consider (2+1)-gravity with vanishing cosmological constant as a constrained dynamical system. By applying Dirac's gauge fixing procedure, we implement the constraints and determine the Dirac bracket on the gauge-invariant phase space.…

General Relativity and Quantum Cosmology · Physics 2011-10-05 Catherine Meusburger , Torsten Schönfeld

The reconstruction of quantum states from a sufficient set of experimental data can be achieved with arbitrarily weak measurement interactions. Since such weak measurements have negligible back-action, the quantum state reconstruction is…

Quantum Physics · Physics 2010-03-16 Holger F. Hofmann

Quantum mechanics in the presence of $\delta$-function potentials is known to be plagued by UV divergencies which result from the singular nature of the potentials in question. The standard method for dealing with these divergencies is by…

High Energy Physics - Theory · Physics 2007-05-23 Alexandr Yelnikov

We give an overview of the two different methods that have been introduced in order to describe the dynamics of constrained quantum systems; the symplectic formulation and the metric formulation. The symplectic method extends the work of…

Quantum Physics · Physics 2015-05-13 Anna C. T. Gustavsson

Dirac formalism of Hamiltonian constraint systems is studied for the noncommutative Abelian Proca field. It is shown that the system of constraints are of second class in agreement with the fact that the Proca field is not guage invariant.…

High Energy Physics - Theory · Physics 2015-05-27 F. Darabi , F. Naderi

A covariant quantization method for physical systems with reducible constraints is presented.

High Energy Physics - Theory · Physics 2007-05-23 J. Stephany , A. Restuccia

Quantum state, in relativistic quantum mechanics, itself turns out to be an entangled state due to its own degrees freedom such as spin and momentum. This peculiar entanglement leaves the transformed state mixed. We consider the fractional…

Mesoscale and Nanoscale Physics · Physics 2012-02-28 S. Arunagiri

Any unitary transformation of quantum computational networks is explicitly decomposed, in an exact and unified form, into a sequence of a limited number of one-qubit quantum gates and the two-qubit diagonal gates that have diagonal unitary…

Quantum Physics · Physics 2007-05-23 Xijia Miao

We develop a complete Hamiltonian approach to the theory of perturbations around any spatially homogeneous spacetime. We employ the Dirac method for constrained systems which is well-suited to cosmological perturbations. We refine the…

General Relativity and Quantum Cosmology · Physics 2023-01-19 Alice Boldrin , Przemysław Małkiewicz

Motivated by certain concepts introduced by the Refined Algebraic Quantization formalism for constrained systems which has been successfully applied within the context of Loop Quantum Gravity, in this paper we propose a phase space…

General Relativity and Quantum Cosmology · Physics 2020-04-08 Jasel Berra-Montiel , Alberto Molgado

A qualitative but formalized representation of microstates is first established quite independently of the quantum mechanical mathematical formalism, exclusively under epistemological-operational-methodological constraints. Then, using this…

Quantum Physics · Physics 2019-07-17 Mioara Mugur-Schächter

The paper develop the alternative formulation of quantum mechanics known as the phase space quantum mechanics or deformation quantization. It is shown that the quantization naturally arises as an appropriate deformation of the classical…

Mathematical Physics · Physics 2011-09-27 Maciej Blaszak , Ziemowit Domanski

In this paper we present a model of Riemannian loop quantum cosmology with a self-adjoint quantum scalar constraint. The physical Hilbert space is constructed using refined algebraic quantization. When matter is included in the form of a…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Karim Noui , Alejandro Perez , Kevin Vandersloot

A general procedure for constructing coherent states, which are eigenstates of annihilation operators, related to quantum mechanical potential problems, is presented. These coherent states, by construction are not potential specific and…

Quantum Physics · Physics 2007-05-23 P. K. Panigrahi , T. Shreecharan , J. Banerji , V. Sundaram

Most states in the Hilbert space are maximally entangled. This fact has proven useful to investigate - among other things - the foundations of statistical mechanics. Unfortunately, most states in the Hilbert space of a quantum many body…

Quantum Physics · Physics 2015-05-30 Alioscia Hamma , Siddhartha Santra , Paolo Zanardi

According to mathematical constructivism, a mathematical object can exist only if there is a way to compute (or "construct") it; so, what is non-computable is non-constructive. In the example of the quantum model, whose Fock states are…

Quantum Physics · Physics 2016-05-11 Arkady Bolotin

This article presents the result that fluctuations and higher moments of a state do not imply quantum corrections in structure functions of constrained systems. Consequences for canonical quantum gravity, whose structure functions encode…

General Relativity and Quantum Cosmology · Physics 2016-02-12 Martin Bojowald , Suddhasattwa Brahma

Starting with the first-order singular Lagrangian containing the redundant variables, the noncommutative quantum mechanics on a curved space is investigated by the constraint star-product quantization formalism of the projection operator…

High Energy Physics - Theory · Physics 2016-10-06 M. Nakamura

After reviewing the hole argument and its relations with initial value problem and general covariance, we shall discuss how much freedom one has to define the physical state of a system in a generally covariant (or gauge covariant) field…

General Relativity and Quantum Cosmology · Physics 2017-04-05 L. Fatibene , M. Ferraris , G. Magnano

In this paper, we carry a detailed study of mechanical systems with configuration space $Q\longrightarrow Q/G$ for which the base $Q/G$ variables are being controlled. The overall system's motion is considered to be induced from the base…

Mathematical Physics · Physics 2009-11-13 Alejandro Cabrera