activity
20152026
most citedThe Universal Approximation Property

74 citations · 120 across the 41 of their papers we have counts for

collaborators
Showing cs.LGShow all

23 papers · 1 filter

cs.LG2026

Certifiably Interpretable Training of ReLU-MLPs for Boolean Tasks with Guaranteed Truth-Table Generalization

Hrad Ghoukasian, Anastasis Kratsios

As compute scales, models evolve, and training algorithms advance, our ability to explain the increasingly powerful AI systems they enable is eroding. To help safeguard interpretab…

cs.LG2026

Algorithmic Foundations of Deep Learning: Complexity-Theoretic Rates and a Characterization of Universal Approximation

Anastasis Kratsios, Simone Brugiapaglia, Bum Jun Kim +2

Feedforward neural network (NN) expressivity is typically studied by emulating optimal basis-expansion schemes. While powerful, this perspective is incomplete: it primarily capture…

cs.LG2026

MEMOA: Massive Mixtures of Online Agents via Mean-Field Decentralized Nash Equilibria

Xuwei Yang, David B. Emerson, Fatemeh Tavakoli +1

In the modern age of large-scale AI, federated learning has become an increasingly important tool for training large populations of AI agents; however, its computational and commun…

cs.LG2026

Adaptivity Under Realizability Constraints: Comparing In-Context and Agentic Learning

Anastasis Kratsios, A. Martina Neuman, Philipp Petersen

We compare in-context learning with fixed queries and agentic learning with adaptive queries for uniform approximation of task families. We consider two settings: an unrestricted r…

cs.LG2026

Neural Operators Can Discover Functional Clusters

Yicen Li, Jose Antonio Lara Benitez, Ruiyang Hong +3

Operator learning is reshaping scientific computing by amortizing inference across infinite families of problems. While neural operators (NOs) are increasingly well understood for…

cs.LG2025

One model to solve them all: 2BSDE families via neural operators

Takashi Furuya, Anastasis Kratsios, Dylan Possamaï +1

We introduce a mild generative variant of the classical neural operator model, which leverages Kolmogorov--Arnold networks to solve infinite families of second-order backward stoch…

cs.LG2025

Autonomous-Flow-Based Generation

Hossein Rouhvarzi, Anastasis Kratsios

We show that using autonomous-flow-based generation, one can universally approximate orientation-preserving diffeomorphisms defined on the cube by Neural ODEs with rate $\mathcal{O…

cs.LG2025

Quantifying The Limits of AI Reasoning: Systematic Neural Network Representations of Algorithms

Anastasis Kratsios, Dennis Zvigelsky, Bradd Hart

A main open question in contemporary AI research is quantifying the forms of reasoning neural networks can perform when perfectly trained. This paper answers this by interpreting r…

cs.LG2025

Neural Operators Which Certifiably Simultaneously Solve Infinitely Many Convex Programs using Logarithmic Rank and Linear Complexity

Anastasis Kratsios, Ariel Neufeld, Philipp Schmocker

Neural operators (NOs) are a class of deep learning models designed to simultaneously solve infinitely many related problems by casting them into an infinite-dimensional space, whe…

cs.LG2025

LoRA Fine-Tuning Without GPUs: A CPU-Efficient Meta-Generation Framework for LLMs

Reza Arabpour, Haitz Sáez de Ocáriz Borde, Anastasis Kratsios

Low-Rank Adapters (LoRAs) have transformed the fine-tuning of Large Language Models (LLMs) by enabling parameter-efficient updates. However, their widespread adoption remains limit…

cs.LG2025

Approximation Rates in Besov Norms and Sample-Complexity of Kolmogorov-Arnold Networks with Residual Connections

Anastasis Kratsios, Bum Jun Kim, Takashi Furuya

Inspired by the Kolmogorov-Arnold superposition theorem, Kolmogorov-Arnold Networks (KANs) have recently emerged as an improved backbone for most deep learning frameworks, promisin…

cs.LG2024

Inverse Entropic Optimal Transport Solves Semi-supervised Learning via Data Likelihood Maximization

Mikhail Persiianov, Arip Asadulaev, Nikita Andreev +5

Learning conditional distributions is a central problem in machine learning, which is typically approached via supervised methods with paired data .…

cs.LG2024

Bridging the Gap Between Approximation and Learning via Optimal Approximation by ReLU MLPs of Maximal Regularity

Ruiyang Hong, Anastasis Kratsios

The foundations of deep learning are supported by the seemingly opposing perspectives of approximation or learning theory. The former advocates for large/expressive models that nee…

cs.LG2024★ 2 cited

Neural Spacetimes for DAG Representation Learning

Haitz Sáez de Ocáriz Borde, Anastasis Kratsios, Marc T. Law +2

We propose a class of trainable deep learning-based geometries called Neural Spacetimes (NSTs), which can universally represent nodes in weighted directed acyclic graphs (DAGs) as…

cs.LG2024

Tighter Learning Guarantees on Digital Computers via Concentration of Measure on Finite Spaces

Anastasis Kratsios, A. Martina Neuman, Gudmund Pammer

Machine learning models with inputs in a Euclidean space , when implemented on digital computers, generalize, and their generalization gap converges to at a rate…

cs.LG2023★ 1 cited

Neural Snowflakes: Universal Latent Graph Inference via Trainable Latent Geometries

Haitz Sáez de Ocáriz Borde, Anastasis Kratsios

The inductive bias of a graph neural network (GNN) is largely encoded in its specified graph. Latent graph inference relies on latent geometric representations to dynamically rewir…

cs.LG2023

Capacity Bounds for Hyperbolic Neural Network Representations of Latent Tree Structures

Anastasis Kratsios, Ruiyang Hong, Haitz Sáez de Ocáriz Borde

We study the representation capacity of deep hyperbolic neural networks (HNNs) with a ReLU activation function. We establish the first proof that HNNs can -isometrical…

cs.LG2023★ 4 cited

Out-of-distributional risk bounds for neural operators with applications to the Helmholtz equation

J. Antonio Lara Benitez, Takashi Furuya, Florian Faucher +3

Despite their remarkable success in approximating a wide range of operators defined by PDEs, existing neural operators (NOs) do not necessarily perform well for all physics problem…

cs.LG2022

Do ReLU Networks Have An Edge When Approximating Compactly-Supported Functions?

Anastasis Kratsios, Behnoosh Zamanlooy

We study the problem of approximating compactly-supported integrable functions while implementing their support set using feedforward neural networks. Our first main result transcr…

cs.LG2022

Designing Universal Causal Deep Learning Models: The Geometric (Hyper)Transformer

Beatrice Acciaio, Anastasis Kratsios, Gudmund Pammer

Several problems in stochastic analysis are defined through their geometry, and preserving that geometric structure is essential to generating meaningful predictions. Nevertheless,…

cs.LG2021

Optimizing Optimizers: Regret-optimal gradient descent algorithms

Philippe Casgrain, Anastasis Kratsios

The need for fast and robust optimization algorithms are of critical importance in all areas of machine learning. This paper treats the task of designing optimization algorithms as…

cs.LG2020

A Canonical Transform for Strengthening the Local -Type Universal Approximation Property

Anastasis Kratsios, Behnoosh Zamanlooy

Most -type universal approximation theorems guarantee that a given machine learning model class is dense in $L^p_μ(\mathbb{…

cs.LG2020★ 22 cited

Non-Euclidean Universal Approximation

Anastasis Kratsios, Eugene Bilokopytov

Modifications to a neural network's input and output layers are often required to accommodate the specificities of most practical learning tasks. However, the impact of such change…