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We derive for Bohmian mechanics topological factors for quantum systems with a multiply-connected configuration space Q. These include nonabelian factors corresponding to what we call holonomy-twisted representations of the fundamental…

Quantum Physics · Physics 2007-05-23 Detlef Duerr , Sheldon Goldstein , James Taylor , Roderich Tumulka , Nino Zanghi

The notion of singular reduction operators, i.e., of singular operators of nonclassical (conditional) symmetry, of partial differential equations in two independent variables is introduced. All possible reductions of these equations to…

Analysis of PDEs · Mathematics 2008-11-04 Michael Kunzinger , Roman O. Popovych

The analytic energy gradients in the atomic orbital representation have recently been published (J. Chem. Phys. 146, 014102, 2017) within the framework of the natural orbital functional theory (NOFT). We provide here an alternative…

Chemical Physics · Physics 2018-02-19 Ion Mitxelena , Mario Piris

In topological quantum computation the geometric details of a particle trajectory are irrelevant; only the topology matters. Taking this one step further, we consider a model of computation that disregards even the topology of the particle…

Quantum Physics · Physics 2011-06-03 Stephen P. Jordan

We consider the decomposition of bounded linear operators on Hilbert spaces in terms of functions forming frames. Similar to the singular-value decomposition, the resulting frame decompositions encode information on the structure and…

Numerical Analysis · Mathematics 2021-05-26 Simon Hubmer , Ronny Ramlau

We define, in a consistent way, non-local pseudo-differential operators acting on a space of analytic functionals. These operators include the fractional derivative case. In this context we show how to solve homogeneous and inhomogeneous…

High Energy Physics - Theory · Physics 2007-05-23 D. G. Barci , C. G. Bollini , L. E. Oxman , M. C. Rocca

In the last two decades, significant effort has been put in understanding and designing so-called structure-preserving numerical methods for the simulation of mechanical systems. Geometric integrators attempt to preserve the geometry…

Numerical Analysis · Mathematics 2018-10-26 David Martín de Diego , Rodrigo T. Sato Martín de Almagro

We first generalise the standard Wigner function to Dirac fermions in curved spacetimes. Secondly, we turn to the Moyal quantisation of systems with constraints. Gravity is used as an example.

General Relativity and Quantum Cosmology · Physics 2007-05-23 Frank Antonsen

In this text, we explore the tools that Projective Differential Geometry can provide for the asymptotic analysis of classical fields on projectively compact manifolds. We emphasise on the case of order 2-compactifications and develop, in…

Differential Geometry · Mathematics 2022-03-08 Jack Borthwick

A key problem in the attempt to quantize the gravitational field is the choice of boundary conditions. These are mixed, in that spatial and normal components of metric perturbations obey different sets of boundary conditions. In the…

High Energy Physics - Theory · Physics 2007-05-23 Ivan G. Avramidi , Giampiero Esposito

We outline the recent classification of differential structures for all main classes of quantum groups. We also outline the algebraic notion of `quantum manifold' and `quantum Riemannian manifold' based on quantum group principal bundles, a…

Quantum Algebra · Mathematics 2007-05-23 S. Majid

We consider a wide class of determinants whose entries are moments of the so-called semiclassical functionals and we show that they are tau functions for an appropriate isomonodromic family which depends on the parameters of the symbols for…

Exactly Solvable and Integrable Systems · Physics 2009-11-13 M. Bertola

This report concerns the problem of dimensionality reduction through information geometric methods on statistical manifolds. While there has been considerable work recently presented regarding dimensionality reduction for the purposes of…

Machine Learning · Statistics 2008-09-30 Kevin M. Carter , Raviv Raich , Alfred O. Hero

We present a detailed numerical study of an alternative approach, named Quantum Non-Demolition Measurement (QNDM), to efficiently estimate the gradients or the Hessians of a quantum observable. This is a key step and a resource-demanding…

Quantum Physics · Physics 2025-04-02 Giovanni Minuto , Dario Melegari , Simone Caletti , Paolo Solinas

Using reduction of spherical functions, we obtain generators of the algebra and the field of invariants for the coadjoint representation of Borel and maximal nilpotent subalgebras of simple Lie algebras.

Representation Theory · Mathematics 2009-11-13 A. N. Panov

In the second part of this paper in micro canonical ensemble the new numerical approach for consideration of quantum dynamics and calculations of the average values of quantum operators and time correlation functions in the Wigner…

Quantum Physics · Physics 2009-10-31 V. Filinov , Yu. Lozovik , A. Filinov , I. Zacharov , A. Oparin

In this paper we compute quantum trajectories arising from Bohm's causal description of quantum mechanics. Our computational methodology is based upon a finite-element moving least-squares method (MWLS) presented recently by Wyatt and…

Quantum Physics · Physics 2009-11-06 Eric R. Bittner

Many basis sets for electronic structure calculations evolve with varying external parameters, such as moving atoms in dynamic simulations, giving rise to extra derivative terms in the dynamical equations. Here we revisit these derivatives…

Quantum Physics · Physics 2017-04-05 Emilio Artacho , David D. O'Regan

Significant progress has been made in our understanding of the analytic structure of FRW wavefunction coefficients, facilitated by the development of efficient algorithms to derive the differential equations they satisfy. Moreover, recent…

High Energy Physics - Theory · Physics 2025-04-08 Shounak De , Andrzej Pokraka

We discuss various issues associated with the calculation of the reduced functional determinant of a special second order differential operator $\boldmath${F}$ =-d^2/d\tau^2+\ddot g/g$, $\ddot g\equiv d^2g/d\tau^2$, with a generic function…

High Energy Physics - Theory · Physics 2015-06-04 A. O. Barvinsky , D. V. Nesterov