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We introduce the Fixed Point Diffusion Model (FPDM), a novel approach to image generation that integrates the concept of fixed point solving into the framework of diffusion-based generative modeling. Our approach embeds an implicit fixed…

Computer Vision and Pattern Recognition · Computer Science 2024-01-18 Xingjian Bai , Luke Melas-Kyriazi

We present a numerical study of lasing modes in diffusive random media with local pumping. The reabsorption of emitted light suppresses the feedback from the unpumped part of the sample and effectively reduces the system size. The lasing…

Disordered Systems and Neural Networks · Physics 2016-08-31 A. Yamilov , X. Wu , H. Cao , A. L. Burin

We consider the Cauchy problem on nonlinear scalar conservation laws with a diffusion-type source term related to an index $s\in \R$ over the whole space $\R^n$ for any spatial dimension $n\geq 1$. Here, the diffusion-type source term…

Analysis of PDEs · Mathematics 2011-04-08 Renjun Duan , Lizhi Ruan , Changjiang Zhu

This work presents a hierarchical model for solute transport in bounded layered porous media with random permeability. The model generalizes the Taylor-Aris dispersion theory to stochastic transport in random layered porous media with a…

Fluid Dynamics · Physics 2018-07-27 Zhijie Xu , Alexandre M. Tartakovsky

We discuss application of methods from the Kraichnan model of turbulent advection to the study of non-equilibrium concentration fluctuations arising during diffusion in liquid mixtures at high Schmidt numbers. This approach treats nonlinear…

Statistical Mechanics · Physics 2022-10-18 Gregory Eyink , Amir Jafari

Diffusion models have shown significant progress in image translation tasks recently. However, due to their stochastic nature, there's often a trade-off between style transformation and content preservation. Current strategies aim to…

Computer Vision and Pattern Recognition · Computer Science 2023-06-08 Gihyun Kwon , Jong Chul Ye

Diffusion on a quenched heterogeneous environment in the presence of bias is considered analytically. The first-passage-time statistics can be applied to obtain the drift and the diffusion coefficient in periodic quenched environments. We…

Statistical Mechanics · Physics 2020-05-06 Takuma Akimoto , Keiji Saito

We consider a certain class of exactly solvable models, describing spectral properties an electron moving in random in time external field with different statistical characteristics. This electron can be band - like or belong to a quantum…

Disordered Systems and Neural Networks · Physics 2026-04-13 E. Z. Kuchinskii , M. V. Sadovskii

Nonlinear gyrotropic medium is a medium, whose natural optical activity depends on the intensity of the incident light wave. The Kuhn's model is used to study nonlinear gyrotropic medium with great success. The Kuhn's model presents itself…

Chaotic Dynamics · Physics 2009-11-13 A. Ugulava , L. Chotorlishvili , K. Nickoladze , G. Mchedlishvili

We introduce a stress/total-pressure formulation for poroelasticity that includes the coupling with steady nonlinear diffusion modified by stress. The nonlinear problem is written in mixed-primal form, coupling a perturbed twofold…

Numerical Analysis · Mathematics 2023-06-27 Bryan Gomez-Vargas , Kent-Andre Mardal , Ricardo Ruiz-Baier , Vegard Vinje

This work investigates the influence of a generic anomalous diffusion model on mass convection in a fluid-saturated porous medium, focusing on superdiffusive regimes. A mathematical model is developed, and tability analyses - both linear…

Fluid Dynamics · Physics 2025-01-08 Antonio Barletta , Pedro Vayssière Brandão , Florinda Capone , Roberta De Luca

A study of the effects of absorption on the nonlinear process of parametric down conversion is presented. Absorption within the nonlinear medium is accounted for by employing the framework of macroscopic QED and the Green tensor…

Quantum Physics · Physics 2015-03-17 J. A. Crosse , Stefan Scheel

The theory of slow-fast gradient systems leads in a natural way to non-equilibrium steady states, because on the slow time scale the fast subsystem stays in steady states that are controlled by the interaction with the slow system. Using…

Analysis of PDEs · Mathematics 2023-10-06 Alexander Mielke

Diffusion models have emerged as a powerful framework in generative modeling, typically relying on optimizing neural networks to estimate the score function via forward SDE simulations. In this work, we propose an alternative method that is…

Numerical Analysis · Mathematics 2025-06-17 Yuehaw Khoo , Mathias Oster , Yifan Peng

Nonlinear and nonlocal effects are discussed in the interaction of laser fields with thermal Rydberg atoms in electromagnetically induced transparency configuration. We show that under the crucial approximation that the time variation in…

Atomic Physics · Physics 2016-09-21 Lida Zhang , Jörg Evers

We propose the feed-forward perturbation-based nonlinearity compensation method using the received signal, which outperforms conventional decision-based ones and eliminates the need for decision feedback. Additionally, combining half-half…

Optics · Physics 2025-12-30 Chuang Xu , Alan Pak Tao Lau

Unique and flexible properties of non-Hermitian photonic systems attract ever-increasing attention via delivering a whole bunch of novel optical effects and allowing for efficient tuning light-matter interactions on nano- and microscales.…

We consider the subdiffusion--absorption process in a system which consists of two different media separated by a thin membrane. The process is described by subdiffusion--absorption equations with fractional Riemann--Liouville time…

Statistical Mechanics · Physics 2018-08-01 Tadeusz Kosztołowicz

We study the propagation of waves in a set of absorbing subwavelength scatterers positioned on a stealth hyperuniform point pattern. We show that spatial correlations in the disorder substantially enhance absorption compared to a fully…

Optics · Physics 2019-03-27 Florian Bigourdan , Romain Pierrat , Rémi Carminati

We consider combining of multiple laser beams into a single near diffraction-limited beam by beam self-focusing (collapse) in a Kerr medium. The beams with the total power above critical are combined in the near field and then propagated in…

Pattern Formation and Solitons · Physics 2016-06-30 Pavel M. Lushnikov , Natalia Vladimirova