English
Related papers

Related papers: Basic quantum mechanics for three Dirac equations …

200 papers

The most general dilaton gravity theory in 2 spacetime dimensions is considered. A Hamiltonian analysis is performed and the reduced phase space, which is two dimensional, is explicitly constructed in a suitable parametrization of the…

General Relativity and Quantum Cosmology · Physics 2009-10-22 D. Louis- Martinez , J. Gegenberg , G. Kunstatter

The Dirac wave function in a curved spacetime is usually defined as a quadruplet of scalar fields. It can alternatively be defined as a four-vector field. We describe these two representations in a common geometrical framework and we prove…

General Relativity and Quantum Cosmology · Physics 2011-10-05 Mayeul Arminjon , Frank Reifler

Geometric properties of operators of quantum Dirac constraints and physical observables are studied in semiclassical theory of generic constrained systems. The invariance transformations of the classical theory -- contact canonical…

General Relativity and Quantum Cosmology · Physics 2008-02-03 A. O. Barvinsky

We have previously presented a version of the Weak Equivalence Principle for a quantum particle as an exact analog of the classical case, based on the Heisenberg picture analysis of free particle motion. Here, we take that to a full…

General Relativity and Quantum Cosmology · Physics 2025-06-17 Otto C. W. Kong

We study the quantum cosmology of a quadratic $f(R)$ theory with a FRW metric, via one of its equivalent Horndeski type actions, where the dynamics of the scalar field is induced. The classical equations of motion and the Weeler-deWitt…

General Relativity and Quantum Cosmology · Physics 2017-06-22 V. Vázquez-Báez , C. Ramírez

A rigorous \textit{ab initio} derivation of the (square of) Dirac's equation for a single particle with spin is presented. The general Hamilton-Jacobi equation for the particle expressed in terms of a background Weyl's conformal geometry is…

Quantum Physics · Physics 2011-07-19 Enrico Santamato , Francesco De Martini

We numerically compute renormalized expectation values of quadratic operators in a quantum field theory (QFT) of free Dirac fermions in curved two-dimensional (Lorentzian) spacetime. First, we use a staggered-fermion discretization to…

General Relativity and Quantum Cosmology · Physics 2020-10-28 Adam G. M. Lewis , Guifré Vidal

A method to construct non-dissipative non-Dirac-hermitian relativistic quantum system that is isospectral with a Dirac-hermitian Hamiltonian is presented. The general technique involves a realization of the basic canonical…

High Energy Physics - Theory · Physics 2011-08-17 Pijush K. Ghosh

The basic principles of the quantum mechanics in the K-field formalism are stated in the paper. The basic distinction of this theory arises from that the quantum theory equations (including well-known Schrodinger, Klein-Gordon and quadratic…

Quantum Physics · Physics 2007-05-23 K. B. Korotchenko

On a static spacetime, the solutions of the Dirac equation are generated by a time-independent Hamiltonian. We study this Hamiltonian and characterize the split into positive and negative energy. We use it to find explicit expressions for…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Wei Min Jin

I consider the longstanding issue of the hermiticity of the Dirac equation in curved spacetime. Instead of imposing hermiticity by adding ad hoc terms, I renormalize the field by a scaling function, which is related to the determinant of…

Quantum Physics · Physics 2026-04-21 Pasquale Marra

For any Dirac theory of quantum gravity governed by a set of well-defined quantum constraints, we discover a universal formula for the exact form of the evolution Hamiltonian operator in a variable quantum reference frame of our…

General Relativity and Quantum Cosmology · Physics 2026-04-20 Chun-Yen Lin

The Hamiltonian formulation of general relativity (GR) is considered in finite space-time and a specific frame of reference given by the diffeo-invariant components of the Fock simplex in terms of the Dirac -- ADM variables. The evolution…

Astrophysics · Physics 2009-11-13 B. M. Barbashov , V. N. Pervushin , A. F. Zakharov , V. A. Zinchuk

We use Dirac's method for the quantization of constrained systems in order to quantize a spatially flat Friedmann-Lema\^{i}tre-Robertson-Walker spacetime in the context of $f(Q)$ cosmology. When the coincident gauge is considered, the…

General Relativity and Quantum Cosmology · Physics 2021-10-22 N. Dimakis , A. Paliathanasis , T. Christodoulakis

A general quantum constraint of the form $C= - \partial_T^2 \otimes B - I\otimes H$ (realized in particular in Loop Quantum Cosmology models) is studied. Group Averaging is applied to define the Hilbert space of solutions and the relational…

General Relativity and Quantum Cosmology · Physics 2010-04-14 Wojciech Kaminski , Jerzy Lewandowski , Tomasz Pawlowski

Proofs of two statements are provided in this paper. First, the authors prove that the formalism of the pseudo-Hermitian quantum mechanics allows describing the Dirac particles motion in arbitrary stationary gravitational fields. Second, it…

General Relativity and Quantum Cosmology · Physics 2011-05-12 M. V. Gorbatenko , V. P. Neznamov

Standard quantum mechanics predicts the non-conservation of state norms and probability when the fundamental requirement of the Hermiticity of the Hamiltonian is relaxed. Biorthogonal quantum mechanics, or the more general metric formalism,…

Quantum Physics · Physics 2025-07-18 Mario Gonzalez , Karin Sim , R. Chitra

A Quantum Walk (QW) simulating the flat $(1 + 2)$D Dirac Eq.\ on a spatial polar grid is constructed. Because fermions are represented by spinors, which do not constitute a representation of the rotation group, but rather of its double…

Quantum Physics · Physics 2020-07-21 Gareth Jay , Pablo Arnault , Fabrice Debbasch

Canonical vacuum gravity is expressed in generally-covariant form in order that spacetime diffeomorphisms be represented within its equal-time phase space. In accordance with the principle of general covariance, the time mapping ${\T}:…

General Relativity and Quantum Cosmology · Physics 2009-02-20 Ioannis Kouletsis

Dirac's leaping insight that the normalized anti-commutator of the {\gamma}^{\mu} matrices must equal the timespace signature {\eta}^{\mu}{\nu} was decisive for the success of his equation. The {\gamma}^{\mu}-s are the same in all Lorentz…

Quantum Physics · Physics 2023-09-25 Sokol Andoni