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Related papers: Generalization of the Hellmann-Feynman theorem

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The Feynman-Hellmann theorem can be derived from the long Euclidean-time limit of correlation functions determined with functional derivatives of the partition function. Using this insight, we fully develop an improved method for computing…

High Energy Physics - Lattice · Physics 2017-07-19 Chris Bouchard , Chia Cheng Chang , Thorsten Kurth , Kostas Orginos , Andre Walker-Loud

We consider classical theories described by Hamiltonians $H(p,q)$ that have a non-degenerate minimum at the point where generalized momenta $p$ and generalized coordinates $q$ vanish. We assume that the sum of squares of generalized momenta…

Quantum Physics · Physics 2025-04-21 Albert Schwarz

(Draft 3) A generalized differential operator on the real line is defined by means of a limiting process. These generalized derivatives include, as a special case, the classical derivative and current studies of fractional differential…

Mathematical Physics · Physics 2018-07-17 Angelo B. Mingarelli

I propose a new and direct connection between classical mechanics and quantum mechanics where I derive the quantum mechanical propagator from a variational principle. This variational principle is Hamilton's modified principle generalized…

Quantum Physics · Physics 2009-12-15 John Hegseth

A generalized quantization principle is considered, which incorporates nontrivial commutation relations of the components of the variables of the quantized theory with the components of the corresponding canonical conjugated momenta…

General Physics · Physics 2016-09-02 Martin Kober

Feynman path integrals formalism for non-relativistic quantum mechanics is revisited. A comparison is made with the cases of light progagation (Huygens principle) and Brownian motion. The difficulties for a physical model behind Feynman…

Quantum Physics · Physics 2025-10-09 Emilio Santos

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

Open systems acquire time-dependent coupling constants through interaction with an external field or environment. We generalize the Lewis-Riesenfeld invariant theorem to open system of quantum fields after second quantization. The…

High Energy Physics - Theory · Physics 2011-07-19 S. P. Kim , A. E. Santana , F. C. Khanna

It is shown that the stochastic model of Fenyes and Nelson can be generalized in such a way that the diffusion constant of the Markov theory becomes a free parameter. This extra freedom allows one to identify quantum mechanics with a class…

Quantum Physics · Physics 2015-06-26 Mark P. Davidson

We propose a Hamiltonian formalism for a generalized Friedmann-Roberson-Walker cosmology model in the presence of both a variable equation of state (EOS) parameter $w(a)$ and a variable cosmological constant $\Lambda(a)$, where $a$ is the…

High Energy Physics - Theory · Physics 2008-11-26 Jie Ren , Xin-He Meng , Liu Zhao

We derive the Helmholtz theorem for nondifferentiable Hamiltonian systems in the framework of Cresson's quantum calculus. Precisely, we give a theorem characterizing nondifferentiable equations, admitting a Hamiltonian formulation.…

Optimization and Control · Mathematics 2016-05-19 Frédéric Pierret , Delfim F. M. Torres

The Hamiltonian constraint system is the canonical formulation of a physical system with a Hamiltonian constrained to vanish. In terms of the canonical variables, we define what we call reference observable, with respect to which other…

General Relativity and Quantum Cosmology · Physics 2012-10-30 Junichi Iwasaki

We formulate quantum mechanics in spacetimes with real-order fractional geometry and more general factorizable measures. In spacetimes where coordinates and momenta span the whole real line, Heisenberg's principle is proven and the…

High Energy Physics - Theory · Physics 2012-10-18 Gianluca Calcagni , Giuseppe Nardelli , Marco Scalisi

The notion of generalized quantum monoids is introduced. It is proved that the quantum coordinate ring of the monoid can be lifted to a quantum hyper-algebra, in which the quantum determinant and quantum Pfaffian are sent to the quantum…

Quantum Algebra · Mathematics 2017-11-06 Naihuan Jing , Jian Zhang

We call a Lebesgue-Feynman measure (LFM) any generalized measure (distribution in the sense of Sobolev and Schwartz) on a locally convex topological vector space E which is translation invariant. In the present paper, we investigate…

Mathematical Physics · Physics 2016-12-21 James Montaldi , Oleg G. Smolyanov

Thermalization of isolated many-body systems is demonstrated by generalizing an approach originally due to von Neumann: For arbitrary initial states with a macroscopically well-defined energy, quantum mechanical expectation values become…

Statistical Mechanics · Physics 2015-07-02 Peter Reimann

The uncertainty principle lies at the heart of quantum physics, and is widely thought of as a fundamental limit on the measurement precisions of incompatible observables. Here we show that the traditional uncertainty relation in fact…

Quantum Physics · Physics 2021-02-03 Jun-Li Li , Cong-Feng Qiao

Quantum measurement problem is still unconsensus since it has existed many years and inspired a large of literature in physics and philosophy. We show it can be subsumed into the quantum theory if we extend the Feynman path integral by…

Quantum Physics · Physics 2012-03-12 Wei Wen

A new formulation of quantum mechanics is proposed based on a new principle that can be considered a generalization of the Born rule. The principle is composed of a mathematical expression and an associated interpretation, and establishes a…

Quantum Physics · Physics 2008-10-31 Bruno Galvan

To any graph with external half-edges and internal masses, we associate canonical integrals which depend non-trivially on particle masses and momenta, and are always finite. They are generalised Feynman integrals which satisfy graphical…

Mathematical Physics · Physics 2023-11-23 Francis Brown