English
Related papers

Related papers: Measurement and self-adjoint operators

200 papers

In order to figure out why quantum physics needs the complex Hilbert space, many attempts have been made to distinguish the C*-algebras and von Neumann algebras in more general classes of abstractly defined Jordan algebras (JB- and…

Mathematical Physics · Physics 2015-03-31 Gerd Niestegge

Whether gravity must be quantized remains one of the biggest open problems in fundamental physics. Classical-quantum hybrid theories have recently attracted attention as a possible framework in which gravity is treated classically yet…

Quantum Physics · Physics 2026-04-14 Masahiro Hotta , Sebastian Murk , Daniel R. Terno

Any two infinite-dimensional (separable) Hilbert spaces are unitarily isomorphic. The sets of all their self-adjoint operators are also therefore unitarily equivalent. Thus if all self-adjoint operators can be observed, and if there is no…

Quantum Physics · Physics 2009-11-06 A. P. Balachandran

What does it take for real-deterministic c-valued (i.e., classical, commuting) variables to comply with the Heisenberg uncertainty principle? Here, we construct a class of real-deterministic c-valued variables out of the weak values…

Quantum Physics · Physics 2021-06-23 Agung Budiyono , Hermawan K. Dipojono

After analyzing Dirac's equation, one can suggest that a well-known quantum-mechanical momentum operator is associated with relativistic momentum, rather than with non-relativistic one. Consideration of relativistic energy and momentum…

Mathematical Physics · Physics 2013-04-01 Gintautas P. Kamuntavičius

In quantum mechanics, the selfadjoint Hilbert space operators play a triple role as observables, generators of the dynamical groups and statistical operators defining the mixed states. One might expect that this is typical of Hilbert space…

Quantum Physics · Physics 2015-03-31 Gerd Niestegge

A hybrid formalism is proposed for interacting classical and quantum sytems. This formalism is mathematically consistent and reduces to standard classical and quantum mechanics in the case of no interaction. However, in the presence of…

Quantum Physics · Physics 2009-11-06 Asher Peres , Daniel Terno

A 4-dimensional Lorentzian static space-time is equivalent to 3-dimensional Euclidean gravity coupled to a massless Klein-field. By canonically quantizing the coupling model in the framework of loop quantum gravity, we obtain a quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Yongge Ma

It is usual to identify initial conditions of classical dynamical systems with mathematical real numbers. However, almost all real numbers contain an infinite amount of information. I argue that a finite volume of space can't contain more…

Quantum Physics · Physics 2021-11-04 Nicolas Gisin

In recent works we have used quantum tools in the analysis of the time evolution of several macroscopic systems. The main ingredient in our approach is the self-adjoint Hamiltonian $H$ of the system $\Sc$. This Hamiltonian quite often, and…

Quantum Physics · Physics 2019-10-23 Fabio Bagarello

The algebra of polynomials in operators that represent generalized coordinate and momentum and depend on the Planck constant is defined. The Planck constant is treated as the parameter taking values between zero and some nonvanishing $h_0$.…

Quantum Physics · Physics 2007-05-23 S. Prvanovic , Z. Maric

Here I explore a novel no-collapse interpretation of quantum mechanics which combines aspects of two familiar and well-developed alternatives, Bohmian mechanics and the many-worlds interpretation. Despite reproducing the empirical…

Quantum Physics · Physics 2015-04-03 Charles Sebens

In the Contextuality-by-Default theory random variables representing measurement outcomes are labeled contextually, i.e., not only by what they measure but also under what conditions (in what contexts) the measurements are made, including…

Quantum Physics · Physics 2018-12-11 Ehtibar N. Dzhafarov

It is shown that in presence of certain external fields a well defined self-adjoint time operator exists, satisfying the standard canonical commutation relations with the Hamiltonian. Examples include uniform electric and gravitational…

Quantum Physics · Physics 2023-12-15 A. M. Schlichtinger , A. Jadczyk

In this paper we analyze two different functional formulations of classical mechanics. In the first one the Jacobi fields are represented by bosonic variables and belong to the vector (or its dual) representation of the symplectic group. In…

Quantum Physics · Physics 2015-06-26 E. Deotto , E. Gozzi , D. Mauro

In this paper, we demonstrate the equivalence between the complex Hilbert space and real Kahler space formulations of quantum mechanics. Complex numbers play an important role in the traditional formulation of quantum mechanics in complex…

Quantum Physics · Physics 2025-04-24 Igor Volovich

A finite dimensional system with a quadratic Hamiltonian constraint is Dirac quantized in holomorphic, antiholomorphic and mixed representations. A unique inner product is found by imposing Hermitian conjugacy relations on an operator…

General Relativity and Quantum Cosmology · Physics 2010-11-01 Jorma Louko

A generalization of classical mechanics is obtained from a complex parametrization of the phase space. The formalism supports complex Hamiltonian functions describing non-conservative classical mechanical systems. A quantization scheme that…

Quantum Physics · Physics 2025-03-25 Sergio Giardino

Quantum mechanics has been formulated in phase space, with the Wigner function as the representative of the quantum density operator, and classical mechanics has been formulated in Hilbert space, with the Groenewold operator as the…

Quantum Physics · Physics 2017-02-23 A. J. Bracken , J. G. Wood

A strong analog classical simulation of general quantum evolution is proposed, which serves as a novel scheme in quantum computation and simulation. The scheme employs the approach of geometric quantum mechanics and quantum informational…

Quantum Physics · Physics 2017-03-16 Dong-Sheng Wang