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On the stabilizer of the graph of linear functions over finite fields

  • Valentino Smaldore , Corrado Zanella and Ferdinando Zullo EMAIL logo
Published/Copyright: January 13, 2025

Abstract

In this paper we will study the action of 𝔽 q n 2 × 2 on the graph of an 𝔽 q -linear function of 𝔽 q n to itself. In particular, we will see that, under certain combinatorial assumptions, its stabilizer (together with the sum and product of matrices) is a field. We will also give some examples where this is not the case. We will also connect such a stabilizer to the right idealizer of the rank-metric code defined by the linear function, and give some structural results in the case where the polynomials are partially scattered.

MSC 2020: 11T06

Communicated by Philipp Habegger


Funding statement: This research was partially supported by the Italian National Group for Algebraic and Geometric Structures and their Applications (GNSAGA - INdAM). The research of the first and third authors was supported by the INdAM - GNSAGA project Tensors over finite fields and their applications, number E53C23001670001. The research of the third author was supported by the “VALERE: VAnviteLli pEr la RicErca” project of the University of Campania “Luigi Vanvitelli” and by the COMBINE from “VALERE: VAnviteLli pEr la RicErca” project of the University of Campania “Luigi Vanvitelli”.

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Received: 2023-10-06
Revised: 2024-11-12
Published Online: 2025-01-13
Published in Print: 2025-06-01

© 2025 Walter de Gruyter GmbH, Berlin/Boston

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