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🔍 jonathan ullman 📂 Mathematics
Showing 2595 results for "jonathan ullman" in Mathematics
Mathematics Preprint PDF DOI

Continuous-time q-learning for mean-field control with common noise, part-I: Theoretical foundations

Zhenjie Ren, Xiaoli Wei, Xiang Yu, Xun Yu Zhou · 2026

This paper investigates the continuous-time counterpart of the Q-function for entropy-regularized mean-field control (MFC) with controlled common noise, coined as q-function by Jia and Zhou (2023) in …

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Mathematics Preprint PDF DOI

Deep Policy Iteration for High-Dimensional Mean-Field Games with Regenerative Reformulation

Shuixin Fang, Shupeng Wang, Zhen Wu, Hui Zhang, Tao Zhou · 2026

This paper develops a deep policy iteration method for high-dimensional finite-horizon mean-field games. We reformulate the game as a regenerative problem with deterministic cycles, which allows polic…

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Mathematics Preprint PDF DOI

Approximations of the Mortensen observer using higher order extended Kalman filters

Tobias Breiten, Justus Ramme, Jesper Schroder · 2026

A polynomial approximation of the minimum energy estimator, also called Mortensen observer, is discussed. The method relies on successive differentiations of an underlying value function and the Hamil…

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Mathematics Preprint PDF DOI

C-PINN: A neural network framework based on the Cord\`{e}s condition for solving linear and fully nonlinear equations in non-divergence form and its applications

Bingcheng Hu, Lixiang Jin, Zhaoxiang Li · 2026

In this paper, we propose a novel Physics-Informed Neural Network (PINN) framework based on the Cord\`{e}s condition for solving both linear and fully nonlinear partial differential equations (PDEs) i…

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Mathematics Preprint PDF DOI

A Continuous-Time Ensemble Kalman-Bucy Smoother for Causal Inference and Model Discovery

Zhang Jiang, Marios Andreou, Sebastian Reich, Nan Chen · 2026

Data assimilation (DA) integrates observational information with model predictions to improve state estimation in complex systems. While filtering provides the basis for online forecasts by using only…

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Mathematics Preprint PDF DOI

Encoded Forward Backward Stochastic Neural Network for High-Dimensional Backward Stochastic Differential Equations and Parabolic Partial Differential Equations

Zhao Zhang, Zhuopeng Hou · 2026

Backward stochastic differential equation (BSDE) provides probabilistic solutions for a class of parabolic partial differential equations (PDEs). DeepBSDE and FBSNN are two deep learning approaches fo…

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Mathematics Preprint PDF DOI

Dual Control of Linear Systems from Bilinear Observations with Belief Space Model Predictive Control

Daniel Cao, Beixi Du, Andrew Lowitt, Sunmook Choi, Sarah Dean, Yahya Sattar · 2026

We study finite-horizon quadratic control of linear systems with bilinear observations, in which the control input affects not only the state dynamics but also the partial observations of the state. I…

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Mathematics Preprint PDF DOI

Regret-Optimal Control for Finite-State Systems

Yishay Polatov, Oron Sabag · 2026

We study the control of finite-state systems driven by exogenous disturbances, and design causal policies that track the performance of a lookahead benchmark controller. This objective is formalized t…

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Mathematics Preprint PDF DOI

Optimal strategies in the all-heads coin game

Peter Pfaffelhuber · 2026

We study a sequential coin-flipping game in which a player starts with~$n$ coins, each landing heads independently with probability~$p$. In each round the player flips all remaining coins and must set…

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Mathematics Preprint PDF DOI

Stackelberg Stochastic Linear-Quadratic Differential Games: A Closed-Loop Equilibrium Approach

Qi Lu, Bowen Ma, Hanxiao Wang · 2026

This paper addresses a Stackelberg stochastic linear-quadratic (LQ) differential game under closed-loop information, a problem inherently time-inconsistent. Existing approaches rely on solving two cou…

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Mathematics Preprint PDF DOI

$H_2/H_{\infty}$ Control for Stochastic Differential Systems with Partial Observation

Changwang Xiao, Nan Yang, Qingxin Meng · 2026

This paper investigates the $H_{2}/H_{\infty}$ control problem for linear stochastic differential systems under partial observation. Unlike existing studies that assume full state accessibility, we co…

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Mathematics Preprint PDF DOI

Discretization error from regularized Reinforcement Learning to continuous-time stochastic control

Huyen Pham, Yuming Paul Zhang, Yuhua Zhu · 2026

This paper establishes a rigorous connection between regularized discrete-time reinforcement learning (RL) and continuous-time stochastic optimal control. Specifically, classical RL algorithms are typ…

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Mathematics Preprint PDF DOI

Co-State Based Data Fusion and Risk Aware Filtering for Spacecraft Navigation and Hazard Prediction

Surya Ratna Prakash D, Soumyendu Raha · 2026

This paper develops a co-state based fusion frame work for spacecraft navigation, consistency monitoring, and hazard forecasting. A differential algebraic co-state is introduced as an instantaneous La…

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Mathematics Preprint PDF DOI

Forward--Inverse Interplay in FEM-Based EEG Source Imaging: Distributional Signatures of Advanced Source Models and Inverse Solvers

Santtu Soderholm, Joonas Lahtinen, Sampsa Pursiainen · 2026

Electroencephalography (EEG) source imaging aims to infer brain activity from electrical potentials measured on the scalp. This is a difficult problem because many different source patterns can explai…

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Mathematics Preprint PDF DOI

Forward-looking evolutionary game dynamics subject to exploration cost

Hidekazu Yoshioka · 2026

We extend classical evolutionary game dynamics based on the momentary action choices of agents by accounting for two elements: forward-looking behavior and exploration cost. We focus on pairwise compa…

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Mathematics Preprint PDF DOI

Perturbation of the time-1 map of a generic volume-preserving $3$-dimensional Anosov flow

Masato Tsujii, Zhiyuan Zhang · 2026

Let $s > 1$ be a large integer, and let $f$ be a diffeomorphism sufficiently close in the $C^{s}$-topology to the time-1 map of a $C^{s}$ generic volume-preserving Anosov flow on a $3$-dimensional com…

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Mathematics Preprint PDF DOI

Minimax optimal dual control -- The single input case

Anders Rantzer · 2026

An explicit solution is derived for the Bellman inequality corresponding to minimax optimal dual control. The minimizing player determines control action as a function of past state measurements and i…

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Mathematics Preprint PDF DOI

Beyond the Bellman Fixed Point: Geometry and Fast Policy Identification in Value Iteration

Donghwan Lee · 2026

Q-value iteration (Q-VI) is usually analyzed through the \(\gamma\)-contraction of the Bellman operator. This argument proves convergence to \(Q^*\), but it gives only a coarse account of when the ind…

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Mathematics Preprint PDF DOI

A note on the Burnside problem for homeomorphism groups of manifolds

Donggyun Seo · 2026

This note studies the Burnside problem for homeomorphism groups of compact connected manifolds. For surfaces, we prove that the identity component of the homeomorphism group is torsion-free precisely …

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Mathematics Preprint PDF DOI

Dynamic Lagrange Multipliers in a Non-concave Utility Framework

Yang Liu, Alexander Schied, Zhenyu Shen · 2026

In continuous-time portfolio selection for non-concave utility functions, the martingale duality approach is widely adopted in complete markets, while the dynamic programming approach may sometimes le…

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