English

Large affine spaces of symplectic forms

Rings and Algebras 2026-07-16 v1

Abstract

Let F be a field and V be a 2n-dimensional vector space over F. In a previous article, we have proved that if F has more than 2n-2 elements then the greatest possible dimension for an affine space of symplectic forms on V is n(n-1). Here, under the same cardinality assumption we study the spaces that have the critical dimension n(n-1). In particular, if the characteristic of F is not 2 the classification of these spaces up to congruence is reduced to: (1) the classification of nonisotropic quadratic forms over F, up to equivalence and multiplication with a nonzero scalar; (2) the classification of nonisotropic Hermitian forms over all quadratic extensions of F, up to equivalence and multiplication by 1-1. In particular, for quadratically closed fields it is shown that there is exactly one solution up to congruence.

Keywords

Cite

@article{arxiv.2607.14648,
  title  = {Large affine spaces of symplectic forms},
  author = {Clément de Seguins Pazzis},
  journal= {arXiv preprint arXiv:2607.14648},
  year   = {2026}
}

Comments

89 pages (including a table of contents)