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We consider the Dirac equation with a generalized uncertainty principle in the presence of the Harmonic interaction and an external magnetic field. By doing the study in the momentum space, the problem solved in an exact analytical manner…

Quantum Physics · Physics 2014-01-23 Hassan Hassanabadi , Saber Zarrinkamar , Elham Maghsoodi

We investigate the validity of the generalized second law of thermodynamics in a universe governed by Horava-Lifshitz gravity. Under the equilibrium assumption, that is in the late-time cosmological regime, we calculate separately the…

High Energy Physics - Theory · Physics 2011-03-28 Mubasher Jamil , Emmanuel N. Saridakis , M. R. Setare

We present a general formalism for the Hamiltonian description of perturbation theory around any spatially homogeneous spacetime. We employ and refine the Dirac method for constrained systems, which is very well-suited to cosmological…

General Relativity and Quantum Cosmology · Physics 2023-01-23 Alice Boldrin

Odd-dimensional Riemannian spaces that are non-orientable, but have a pin structure, require the consideration of the twisted adjoint representation of the corresponding pin group. It is shown here how the Dirac operator should be modified,…

High Energy Physics - Theory · Physics 2011-04-15 Andrzej Trautman

We propose a generalization of two classes of Lie-Hamilton systems on the Euclidean plane to two-dimensional curved spaces, leading to novel Lie-Hamilton systems on Riemannian spaces (flat $2$-torus, product of hyperbolic lines, sphere and…

Mathematical Physics · Physics 2024-11-26 Rutwig Campoamor-Stursberg , Oscar Carballal , Francisco J. Herranz

We consider quantum dynamics for which the strict adiabatic approximation fails but which do not escape too far from the adiabatic limit. To treat these systems we introduce a generalisation of the time dependent wave operator theory which…

Quantum Physics · Physics 2015-06-16 David Viennot

We consider Dirac-Schr\"odinger operators over odd-dimensional Euclidean space. The conditions for the potential are based on those of C. Callias in his famous paper on the corresponding index problem. However, we treat the case where the…

Spectral Theory · Mathematics 2025-06-03 Oliver Fürst

We advocate that the dual picture of spacetime noncommutativity , i.e. the existence of a curved momentum space, could be a way out to solve some of the open conceptual problems in the field, such as the basis dependence of observables. In…

General Physics · Physics 2025-12-10 S. A. Franchino-Viñas

In this paper we discuss geometric torsion in terms of a distinguished class of Dirac operators. We demonstrate that from this class of Dirac operators a variational problem for torsion can be derived similar to that of Yang-Mills gauge…

Mathematical Physics · Physics 2014-07-15 Tolksdorf Juergen

The formalism for histories-based generalized quantum mechanics developed in two earlier papers is applied to the treatment of histories (of particles or fields or more general objects) in curved spacetimes (which need not admit foliation…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Tulsi Dass , Yogesh N. Joglekar

We propose the construction of equations of motion based on symmetries in quantum-mechanical systems, using Heisenberg's uncertainty principle as a minimal foundation. From canonical operators, two spaces of conjugate operators are…

Quantum Physics · Physics 2025-08-15 Enrique Casanova , José Rojas , Melvin Arias

In this contribution, we study spacetimes of cosmological interest, without making any symmetry assumptions. We prove a rigid Hawking singularity theorem for positive cosmological constant, which sharpens known results. In particular, it…

General Relativity and Quantum Cosmology · Physics 2026-02-16 Gregory J. Galloway , Leonardo García-Heveling

When aiming to apply mathematical results of non-commutative geometry to physical problems the question arises how they translate to a context in which only a part of the spectrum is known. In this article we aim to detect when a…

Mathematical Physics · Physics 2020-03-18 Lisa Glaser , Abel Stern

The equation of the spin-$\frac{1}{2}$ particles in the Friedmann-Lema\^itre-Robertson-Walker spacetime is investigated. The retarded and advanced fundamental solutions to the Dirac operator and generalized Dirac operator as well as the…

Mathematical Physics · Physics 2021-08-13 Karen Yagdjian

We give from first principles the non-relativistic limit of scalar and Dirac fields in curved spacetime. We aim to find general relativistic corrections to the quantum theory of particles affected by Newtonian gravity, a regime nowadays…

High Energy Physics - Theory · Physics 2023-06-06 Riccardo Falcone , Claudio Conti

The quantum measurement axiom dictates that physical observables and in particular the Hamiltonian must be diagonalizable and have a real spectrum. For a time-independent Hamiltonian (with a discrete spectrum) these conditions ensure the…

Quantum Physics · Physics 2009-11-13 Ali Mostafazadeh

General Hardy-Carleman type inequalities for Dirac operators are proved. New inequalities are derived involving particular traditionally used weight functions. In particular, a version of the Agmon inequality and Treve type inequalities are…

Spectral Theory · Mathematics 2015-10-28 Alexandra Enblom

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

Fields of spin $s \geq 1/2$ satisfying wave equations in a curved space obey the Huygens principle under certain conditions clarified by a known theorem. Here this theorem is generalized to spin zero and applied to an inflaton field in de…

General Relativity and Quantum Cosmology · Physics 2019-01-04 Valerio Faraoni

First, the present work is concerned with generalising constructions and results in quantum field theory on curved spacetimes from the well-known case of the Klein-Gordon field to Dirac fields. To this end, the enlarged algebra of…

General Relativity and Quantum Cosmology · Physics 2010-10-22 Thomas-Paul Hack