collaborators

6 papers

cs.CC2026

The Complexity of Verifying Feedforward Neural Networks in Quantised Settings

Eric Alsmann, Martin Lange, Marco Sälzer

We investigate the computational complexity of neural network verification in quantised settings. We distinguish three classes of Feedforward Neural Networks (FNNs): rational FNNs…

cs.LG2026

The Polynomial Counting Capabilities of Message Passing Neural Networks

Marco Sälzer, Pascal Bergsträßer, Anthony W. Lin

The counting power of Message Passing Neural Networks (MPNN) has been the subject of many recent papers, showing that they can express logic that involves counting up to a threshol…

cs.LG2025

The Logical Expressiveness of Temporal GNNs via Two-Dimensional Product Logics

Marco Sälzer, Przemysław Andrzej Wałęga, Martin Lange

In recent years, the expressive power of various neural architectures -- including graph neural networks (GNNs), transformers, and recurrent neural networks -- has been characteris…

cs.LO2025

Verifying Quantized Graph Neural Networks is PSPACE-complete

Marco Sälzer, François Schwarzentruber, Nicolas Troquard

In this paper, we investigate the verification of quantized Graph Neural Networks (GNNs), where some fixed-width arithmetic is used to represent numbers. We introduce the linear-co…

cs.AI2025

A Logic for Reasoning About Aggregate-Combine Graph Neural Networks

Pierre Nunn, Marco Sälzer, François Schwarzentruber +1

We propose a modal logic in which counting modalities appear in linear inequalities. We show that each formula can be transformed into an equivalent graph neural network (GNN). We…

cs.LO2025

Transformer Encoder Satisfiability: Complexity and Impact on Formal Reasoning

Marco Sälzer, Eric Alsmann, Martin Lange

We analyse the complexity of the satisfiability problem, or similarly feasibility problem, (trSAT) for transformer encoders (TE), which naturally occurs in formal verification or i…