Topology and Geometry of the Learning Space of ReLU Networks: Connectivity and Singularities

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Nurisso, Marco, Leroy, Pierrick, Petri, Giovanni, Vaccarino, Francesco
Format: Preprint
Veröffentlicht: 2026
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866912866500608000
author Nurisso, Marco
Leroy, Pierrick
Petri, Giovanni
Vaccarino, Francesco
author_facet Nurisso, Marco
Leroy, Pierrick
Petri, Giovanni
Vaccarino, Francesco
contents Understanding the properties of the parameter space in feed-forward ReLU networks is critical for effectively analyzing and guiding training dynamics. After initialization, training under gradient flow decisively restricts the parameter space to an algebraic variety that emerges from the homogeneous nature of the ReLU activation function. In this study, we examine two key challenges associated with feed-forward ReLU networks built on general directed acyclic graph (DAG) architectures: the (dis)connectedness of the parameter space and the existence of singularities within it. We extend previous results by providing a thorough characterization of connectedness, highlighting the roles of bottleneck nodes and balance conditions associated with specific subsets of the network. Our findings clearly demonstrate that singularities are intricately connected to the topology of the underlying DAG and its induced sub-networks. We discuss the reachability of these singularities and establish a principled connection with differentiable pruning. We validate our theory with simple numerical experiments.
format Preprint
id arxiv_https___arxiv_org_abs_2602_00693
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Topology and Geometry of the Learning Space of ReLU Networks: Connectivity and Singularities
Nurisso, Marco
Leroy, Pierrick
Petri, Giovanni
Vaccarino, Francesco
Machine Learning
Algebraic Geometry
Algebraic Topology
68T07 (Primary) 57N65, 14R05 (Secondary)
I.2.6
Understanding the properties of the parameter space in feed-forward ReLU networks is critical for effectively analyzing and guiding training dynamics. After initialization, training under gradient flow decisively restricts the parameter space to an algebraic variety that emerges from the homogeneous nature of the ReLU activation function. In this study, we examine two key challenges associated with feed-forward ReLU networks built on general directed acyclic graph (DAG) architectures: the (dis)connectedness of the parameter space and the existence of singularities within it. We extend previous results by providing a thorough characterization of connectedness, highlighting the roles of bottleneck nodes and balance conditions associated with specific subsets of the network. Our findings clearly demonstrate that singularities are intricately connected to the topology of the underlying DAG and its induced sub-networks. We discuss the reachability of these singularities and establish a principled connection with differentiable pruning. We validate our theory with simple numerical experiments.
title Topology and Geometry of the Learning Space of ReLU Networks: Connectivity and Singularities
topic Machine Learning
Algebraic Geometry
Algebraic Topology
68T07 (Primary) 57N65, 14R05 (Secondary)
I.2.6
url https://arxiv.org/abs/2602.00693