Gradient Flow Polarizes Softmax Outputs towards Low-Entropy Solutions

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Varre, Aditya, Rofin, Mark, Flammarion, Nicolas
Formato: Preprint
Publicado: 2026
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866918375659143168
author Varre, Aditya
Rofin, Mark
Flammarion, Nicolas
author_facet Varre, Aditya
Rofin, Mark
Flammarion, Nicolas
contents Understanding the intricate non-convex training dynamics of softmax-based models is crucial for explaining the empirical success of transformers. In this article, we analyze the gradient flow dynamics of the value-softmax model, defined as ${L}(\mathbf{V} σ(\mathbf{a}))$, where $\mathbf{V}$ and $\mathbf{a}$ are a learnable value matrix and attention vector, respectively. As the matrix times softmax vector parameterization constitutes the core building block of self-attention, our analysis provides direct insight into transformer's training dynamics. We reveal that gradient flow on this structure inherently drives the optimization toward solutions characterized by low-entropy outputs. We demonstrate the universality of this polarizing effect across various objectives, including logistic and square loss. Furthermore, we discuss the practical implications of these theoretical results, offering a formal mechanism for empirical phenomena such as attention sinks and massive activations.
format Preprint
id arxiv_https___arxiv_org_abs_2603_06248
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Gradient Flow Polarizes Softmax Outputs towards Low-Entropy Solutions
Varre, Aditya
Rofin, Mark
Flammarion, Nicolas
Machine Learning
Optimization and Control
Understanding the intricate non-convex training dynamics of softmax-based models is crucial for explaining the empirical success of transformers. In this article, we analyze the gradient flow dynamics of the value-softmax model, defined as ${L}(\mathbf{V} σ(\mathbf{a}))$, where $\mathbf{V}$ and $\mathbf{a}$ are a learnable value matrix and attention vector, respectively. As the matrix times softmax vector parameterization constitutes the core building block of self-attention, our analysis provides direct insight into transformer's training dynamics. We reveal that gradient flow on this structure inherently drives the optimization toward solutions characterized by low-entropy outputs. We demonstrate the universality of this polarizing effect across various objectives, including logistic and square loss. Furthermore, we discuss the practical implications of these theoretical results, offering a formal mechanism for empirical phenomena such as attention sinks and massive activations.
title Gradient Flow Polarizes Softmax Outputs towards Low-Entropy Solutions
topic Machine Learning
Optimization and Control
url https://arxiv.org/abs/2603.06248