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20152026
most citedA Unified Theory of Decentralized SGD with Changing Topology and Local Updates

163 citations · 496 across the 40 of their papers we have counts for

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Showing 2026Show all

8 papers · 1 filter

math.OC2026

Curvature-Scaled Sharpness-Aware Minimization: Convergence Beyond Smoothness

Dimitris Oikonomou, Nicolas Loizou

Sharpness-Aware Minimization (SAM) has established itself as a widely used method for training deep neural networks. Despite its popularity, existing convergence guarantees for SAM…

math.OC2026

Extragradient and Past Extragradient Methods for -Lipschitz Variational Inequalities

Ezra Greenberg, Nicolas Loizou

Variational inequalities (VIs) capture a broad class of optimization problems central to modern machine learning, including min-max optimization and equilibrium computation in mult…

math.OC2026

Dual-Anchor Acceleration Is Near-Optimal for Stochastic Monotone Root-Finding

TaeHo Yoon, Nicolas Loizou

Among distinct optimal acceleration mechanisms for deterministic monotone root-finding problems and fixed-point problems, dual-anchoring has recently been shown to admit a more rob…

math.OC2026

Polyak-Type Extragradient Methods for Monotone Root-Finding Problems

TaeHo Yoon, Sayantan Choudhury, Ezra Greenberg +1

We study Polyak-type step-size selection for extragradient methods for solving deterministic and stochastic monotone root-finding problems. We show that the known projection-type c…

math.OC2026

Direct Acceleration of Stochastic Root-Finding Without Variance Reduction and Regularization

TaeHo Yoon, Nicolas Loizou

Acceleration for deterministic root-finding problems has been extensively studied in recent years; specifically, the anchor-based, or Halpern-type methods achieve optimal convergen…

math.OC2026

On Same-Sample and Independent-Sample Stochastic Extragradient for Monotone Variational Inequalities

TaeHo Yoon, Nicolas Loizou

We study stochastic extragradient (SEG) methods for solving monotone variational inequality problems (VIPs) over a feasible set. Although extragradient is a foundational algorithm…

math.OC2026

Adaptive Sharpness-Aware Minimization with a Polyak-type Step size: A Theory-Grounded Scheduler

Dimitris Oikonomou, Nicolas Loizou

Sharpness-Aware Minimization (SAM) has established itself as a powerful and widely adopted optimizer for training machine learning models. By explicitly minimizing the sharpness of…

cs.LG2026

Certified Robustness from Approximate Gaussian Mixture Structures in Pretrained Latent Spaces

Konstantinos Emmanouilidis, Tianjiao Ding, Nghia Nguyen +2

Deep learning models are vulnerable to adversarial perturbations, raising important concerns for safety-critical deployment. Empirical defenses can achieve strong robustness in pra…