Results 51 to 60 of about 1,079 (166)
Hamilton-Pontryagin Integrators on Lie Groups [PDF]
, 2007 In this thesis structure-preserving time integrators for mechanical systems whose configuration space is a Lie group are derived from a Hamilton-Pontryagin (HP) variational principle.
Bou-Rabee, Nawaf Mohammed
core +1 more source
Systematic corrections to the Thomas–Fermi approximation without a gradient expansion
New Journal of Physics, 2018 We improve on the Thomas–Fermi approximation for the single-particle density of fermions by introducing inhomogeneity corrections. Rather than invoking a gradient expansion, we relate the density to the unitary evolution operator for the given effective ...
Thanh Tri Chau +3 more
doaj +1 more source
The Canadian Journal of Chemical Engineering, Volume 104, Issue 6, Page 3018-3037, June 2026.Abstract We develop a delay‐aware estimation and control framework for a non‐isothermal axial dispersion tubular reactor modelled as a coupled parabolic‐hyperbolic PDE system with recycle‐induced state delay. The infinite‐dimensional dynamics are preserved without spatial discretization by representing the delay as a transport PDE and adopting a late ...
Behrad Moadeli, Stevan Dubljevic
wiley +1 more source
Time‐Adaptive HénonNets for Separable Hamiltonian Systems
Proceedings in Applied Mathematics and Mechanics, Volume 26, Issue 2, June 2026.ABSTRACT Measurement data is often sampled irregularly, i.e., not on equidistant time grids. This is also true for Hamiltonian systems. However, existing machine learning methods, which learn symplectic integrators, such as SympNets and HénonNets still require training data generated by fixed step sizes.
Konrad Janik, Peter Benner
wiley +1 more source
Symplectic integration of Hamiltonian systems using polynomial maps
, 2001 In order to perform numerical studies of long-term stability in nonlinear Hamiltonian systems, one needs a numerical integration algorithm which is symplectic. Further, this algorithm should be fast and accurate.
Rangarajan, Govindan +1 more
core +1 more source
Bayesian Full‐Waveform Monitoring of CO2 Storage With Fluid‐Flow Priors via Generative Modeling
Journal of Geophysical Research: Machine Learning and Computation, Volume 3, Issue 3, June 2026.Abstract Quantitative monitoring of subsurface changes is essential for ensuring the safety of geological CO2 ${\text{CO}}_{2}$ sequestration. Full‐waveform monitoring (FWM) can resolve these changes at high spatial resolution, but conventional deterministic inversion lacks uncertainty quantification and incorporates only limited prior information ...
Haipeng Li +3 more
wiley +1 more source
Symplectic tracking through straight three dimensional fields by a method of generating functions
Physical Review Accelerators and Beams, 2016 For simulating single-particle trajectories, the derivation of final coordinates from known initial coordinates through arbitrary electromagnetic fields is of key interest in accelerator physics.
M. Titze, J. Bahrdt, G. Wüstefeld
doaj +1 more source
Probabilistic correlation functions of the Schwarzian field theory
Proceedings of the London Mathematical Society, Volume 132, Issue 6, June 2026.Abstract We study correlation functions of the probabilistic Schwarzian field theory. We compute cross‐ratio correlation functions exactly in the case when the corresponding Wilson lines do not intersect, confirming predictions made in the physics literature via limit of the conformal bootstrap and the DOZZ formula.
Ilya Losev
wiley +1 more source
Symplectic integration of PDEs using clebsch variables
, 2019 Many PDEs (Burgers' equation, KdV, Camassa-Holm, Euler's fluid equations,. . . ) can be formulated as infinite-dimensional Lie-Poisson systems. These are Hamiltonian systems on manifolds equipped with Poisson brackets.
McLachlan, Robert I. +2 more
core +1 more source
Hybrid symplectic integrators for planetary dynamics [PDF]
Monthly Notices of the Royal Astronomical Society, 2019 Abstract Hybrid symplectic integrators such as MERCURY are widely used to simulate complex dynamical phenomena in planetary dynamics that could otherwise not be investigated. A hybrid integrator achieves high accuracy during close encounters by using a high-order integration scheme for the duration of the encounter while otherwise using ...
Ari Silburt +8 more
openaire +2 more sources