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A genuinely three-dimensional system, viz. the hyperbolic 4-sphere scattering system, is investigated with classical, semiclassical, and quantum mechanical methods at various center-to-center separations of the spheres. The efficiency and…

Chaotic Dynamics · Physics 2009-11-10 J. Main , E. Atilgan , H. S. Taylor , G. Wunner

Current test- or compression-time adaptation image compression (TTA-IC) approaches, which leverage both latent and decoder refinements as a two-step adaptation scheme, have potentially enhanced the rate-distortion (R-D) performance of…

Computer Vision and Pattern Recognition · Computer Science 2024-10-17 Kecheng Chen , Pingping Zhang , Tiexin Qin , Shiqi Wang , Hong Yan , Haoliang Li

A recently developed density functional method, within Hohenberg-Kohn-Sham framework, is used for faithful description of atoms, molecules in Cartesian coordinate grid, by using an LCAO-MO ansatz. Classical Coulomb potential is obtained by…

Chemical Physics · Physics 2013-07-16 Amlan K. Roy

We introduce a new density for the representation of quantum states on phase space. It is constructed as a weighted difference of two smooth probability densities using the Husimi function and first-order Hermite spectrograms. In contrast…

Mathematical Physics · Physics 2016-03-07 Johannes Keller , Caroline Lasser , Tomoki Ohsawa

In this work, we put forward the theoretical foundation toward thermodynamics of quantum impurity systems measurable in experiments. The theoretical developments involve the identifications on two types of thermodynamic entanglement…

Quantum Physics · Physics 2021-06-24 Hong Gong , Yao Wang , Hou-Dao Zhang , Rui-Xue Xu , Xiao Zheng , YiJing Yan

A recent quantum simulation of observables of the kicked Ising model on 127 qubits implemented circuits that exceed the capabilities of exact classical simulation. We show that several approximate classical methods, based on sparse Pauli…

Quantum Physics · Physics 2024-01-30 Tomislav Begušić , Johnnie Gray , Garnet Kin-Lic Chan

We measure the coherent scattering of low-intensity, near-resonant light by a cloud of laser-cooled two-level rubidium atoms with a size comparable to the wavelength of light. We isolate a two-level atomic structure by applying a 300G…

An accurate treatment of electronic spectra in large systems with a technique such as time dependent density functional theory (TDDFT) is computationally challenging. Due to the Nyquist sampling theorem, direct real time simulations must be…

Materials Science · Physics 2024-01-17 Matthias Kick , Ezra Alexander , Anton Beiersdorfer , Troy Van Voorhis

An emissivity formula is derived using the generalised Fermi-Weizacker-Williams method of virtual photons which accounts for the recoil the charged particle experiences as it emits radiation. It is found that through this derivation the…

Plasma Physics · Physics 2015-12-09 J. L. Martins , M. Vranic , T. Grismayer , J. Vieira , R. A. Fonseca , L. O. Silva

Complex phenomena in engineering and the sciences are often modeled with computationally intensive feed-forward simulations for which a tractable analytic likelihood does not exist. In these cases, it is sometimes necessary to estimate an…

Methodology · Statistics 2020-06-18 Niccolò Dalmasso , Ann B. Lee , Rafael Izbicki , Taylor Pospisil , Ilmun Kim , Chieh-An Lin

Image compression under ultra-low bitrates remains challenging for both conventional learned image compression (LIC) and generative vector-quantized (VQ) modeling. Conventional LIC suffers from severe artifacts due to heavy quantization,…

Computer Vision and Pattern Recognition · Computer Science 2025-11-24 Lei Lu , Yize Li , Yanzhi Wang , Wei Wang , Wei Jiang

Many phenomena of strongly correlated materials are encapsulated in the Fermi-Hubbard model whose thermodynamical properties can be computed from its grand canonical potential according to standard procedures. In general, there is no closed…

Quantum Physics · Physics 2016-03-09 Pierre-Luc Dallaire-Demers , Frank K. Wilhelm

The Mixed Quantum-Classical Initial Value Representation (MQC-IVR) is a recently introduced approximate semiclassical (SC) method for the calculation of real-time quantum correlation functions. MQC-IVR employs a modified Filinov filtration…

Chemical Physics · Physics 2017-09-25 Matthew S. Church , Sergey V. Antipov , Nandini Ananth

This work describes a new 1D hybrid approach for modeling atmospheric pressure discharges featuring complex chemistry. In this approach electrons are described fully kinetically using Particle-In-Cell/Monte-Carlo (PIC/MCC) scheme, whereas…

Plasma Physics · Physics 2016-01-20 Denis Eremin , Torben Hemke , Thomas Mussenbrock

The goal of this study is to introduce a unified computational framework for simulating random iteration equations (RIE), understood as iteration equations containing random variables. The novelty of this work is that full probability…

Dynamical Systems · Mathematics 2026-04-08 Wolfgang Hoegele

Density level sets can be estimated using plug-in methods, excess mass algorithms or a hybrid of the two previous methodologies. The plug-in algorithms are based on replacing the unknown density by some nonparametric estimator, usually the…

Statistics Theory · Mathematics 2016-11-26 A. Rodríguez-Casal , P. Saavedra-Nieves

We discuss the effective infrared theory governing a light scalar's long wavelength dynamics in de Sitter spacetime. We show how the separation of scales around the physical curvature radius $k/a \sim H$ can be performed consistently with a…

General Relativity and Quantum Cosmology · Physics 2017-05-10 Ian Moss , Gerasimos Rigopoulos

Exploratory variational pseudopotential density functional calculations are performed for the electronic properties of many-electron systems in the 3D cartesian coordinate grid (CCG). The atom-centered localized gaussian basis set,…

Chemical Physics · Physics 2015-05-18 Amlan K Roy

In this survey paper we review classical results and recent progress about a certain topic in the spectral theory of two-dimensional canonical systems. Namely, we consider the questions whether the spectrum $\sigma$ is discrete, and if it…

Spectral Theory · Mathematics 2025-04-02 Jakob Reiffenstein , Harald Woracek

Dispersion of a passive scalar from concentrated sources in fully developed turbulent channel flow is studied with the probability density function (PDF) method. The joint PDF of velocity, turbulent frequency and scalar concentration is…

Fluid Dynamics · Physics 2010-03-24 J. Bakosi , P. Franzese , Z. Boybeyi