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A method for the nonintrusive and structure-preserving model reduction of canonical and noncanonical Hamiltonian systems is presented. Based on the idea of operator inference, this technique is provably convergent and reduces to a…

Machine Learning · Computer Science 2023-06-27 Anthony Gruber , Irina Tezaur

An equation is obtained to find the Lagrangian for a one-dimensional autonomous system. The continuity of the first derivative of its constant of motion is assumed. This equation is solved for a generic nonconservative autonomous system…

Mathematical Physics · Physics 2009-11-10 G. Gonzalez

Zeroth-order methods are extensively used in machine learning applications where gradients are infeasible or expensive to compute, such as black-box attacks, reinforcement learning, and language model fine-tuning. Existing optimization…

Machine Learning · Computer Science 2025-11-12 Liang Zhang , Bingcong Li , Kiran Koshy Thekumparampil , Sewoong Oh , Michael Muehlebach , Niao He

We present a scalable Bayesian model for low-rank factorization of massive tensors with binary observations. The proposed model has the following key properties: (1) in contrast to the models based on the logistic or probit likelihood,…

Machine Learning · Statistics 2015-08-19 Changwei Hu , Piyush Rai , Lawrence Carin

Dyson's integration theorem is widely used in the computation of eigenvalue correlation functions in Random Matrix Theory. Here we focus on the variant of the theorem for determinants, relevant for the unitary ensembles with Dyson index…

Mathematical Physics · Physics 2008-11-26 Gernot Akemann , Leonid Shifrin

A simple pseudo-Hamiltonian formulation is proposed for the linear inhomogeneous systems of ODEs. In contrast to the usual Hamiltonian mechanics, our approach is based on the use of non-stationary Poisson brackets, i.e. corresponding…

Quantum Physics · Physics 2009-11-11 V. G. Kupriyanov , S. L. Lyakhovich , A. A. Sharapov

Just because the propagator of some field obeys a de Sitter invariant equation does not mean it possesses a de Sitter invariant solution. The classic example is the propagator of a massless, minimally coupled scalar. We show that the same…

General Relativity and Quantum Cosmology · Physics 2011-12-30 S. P. Miao , N. C. Tsamis , R. P. Woodard

This paper provides a counterexample about the asymptotic behavior of the solutions of a discounted Hamilton-Jacobi equation, as the discount factor vanishes. The Hamiltonian of the equation is a 1-dimensional continuous and coercive…

Analysis of PDEs · Mathematics 2018-01-22 Bruno Ziliotto

A method is presented for computing minimal answers in disjunctive deductive databases under the disjunctive stable model semantics. Such answers are constructed by repeatedly extending partial answers. Our method is complete (in that every…

Logic in Computer Science · Computer Science 2007-05-23 C. A. Johnson

The general solution of SUSY intertwining relations for three-dimensional Schr\"odinger operators is built using the class of second order supercharges with nondegenerate constant metric. This solution includes several models with arbitrary…

High Energy Physics - Theory · Physics 2009-06-12 F. Cannata , M. V. Ioffe , D. N. Nishnianidze

We show that a pair of coupled nonlinear oscillators, of which one oscillator has positive and the other one negative damping of equal rate, can form a Hamiltonian system. Small-amplitude oscillations in this system are governed by a…

Exactly Solvable and Integrable Systems · Physics 2014-05-28 I V Barashenkov , Mariagiovanna Gianfreda

The dilation method is a practical way to experimentally simulate non-Hermitian, especially $\cal PT$-symmetric quantum systems. However, the time-dependent dilation problem cannot be explicitly solved in general. In this paper, we present…

Quantum Physics · Physics 2022-06-20 Minyi Huang , Ray-Kuang Lee , Qing-hai Wang , Guo-Qiang Zhang , Junde Wu

We consider the algebra of massive fermions restricted to a diamond in two-dimensional Minkowski spacetime, and in the Minkowski vacuum state. While the massless modular Hamiltonian is known for this setting, the derivation of the massive…

High Energy Physics - Theory · Physics 2024-12-17 Daniela Cadamuro , Markus B. Fröb , Christoph Minz

Many combinatorial optimization problems can be mapped to finding the ground states of the corresponding Ising Hamiltonians. The physical systems that can solve optimization problems in this way, namely Ising machines, have been attracting…

Emerging Technologies · Computer Science 2017-10-16 Tianshi Wang , Jaijeet Roychowdhury

The reduction of Hamiltonian systems aims to build smaller reduced models, valid over a certain range of time and parameters, in order to reduce computing time. By maintaining the Hamiltonian structure in the reduced model, certain…

Numerical Analysis · Mathematics 2024-09-17 Raphaël Côte , Emmanuel Franck , Laurent Navoret , Guillaume Steimer , Vincent Vigon

The properties of static spherically symmetric black holes, which are both electrically and magnetically charged, and which are coupled to the dilaton in the presence of a cosmological constant, Lambda, are considered. It is shown that…

High Energy Physics - Theory · Physics 2010-04-06 S. J. Poletti , J. Twamley , D. L. Wiltshire

The dynamical algebra associated to a family of isospectral oscillator Hamiltonians is studied through the analysis of its representation in the basis of energy eigenstates. It is shown that this representation becomes similar to that of…

High Energy Physics - Theory · Physics 2009-09-25 David J. Fernández C. , Luis M. Nieto , Oscar Rosas-Ortiz

We extend the modeling framework of port-Hamiltonian descriptor systems to include under- and over-determined systems and arbitrary differentiable Hamiltonian functions. This structure is associated with a Dirac structure that encloses its…

Optimization and Control · Mathematics 2019-03-26 Volker Mehrmann , Riccardo Morandin

A large toolbox of numerical schemes for dispersive equations has been established, based on different discretization techniques such as discretizing the variation-of-constants formula (e.g., exponential integrators) or splitting the full…

Numerical Analysis · Mathematics 2024-05-20 Frédéric Rousset , Katharina Schratz

The transition from rotational to discontinuous behavior of the return map of the perturbed oscillators-step system, a paradigm model for a perturbation of a pseudo-integrable Hamiltonian impact system, is studied. The form of the return…

Chaotic Dynamics · Physics 2025-09-30 Idan Pazi , Alexandra Zobova , Vered Rom-Kedar