On $k$-universal quadratic lattices over unramified dyadic local fields

TL;DR

This paper classifies $k$-universal quadratic forms over unramified dyadic local fields, providing a comprehensive understanding of their structure based on Jordan splittings and fundamental invariants.

Contribution

It offers a complete classification of $k$-universal quadratic forms over unramified dyadic local fields, linking their properties to Jordan splitting invariants.

Findings

Complete classification of $k$-universal quadratic forms

Characterization using Jordan splitting invariants

Explicit criteria for $k$-universality

Abstract

Let $k$ be a positive integer and let $F$ be a finite unramified extension of $\mathbb{Q}_2$ with ring of integers $\mathcal{O}_F$. An integral (resp. classic) quadratic form over $\mathcal{O}_F$ is called $k$-universal (resp. classically $k$-universal) if it represents all integral (resp. classic) quadratic forms of dimension $k$. In this paper, we provide a complete classification of $k$-universal and classically $k$-universal quadratic forms over $\mathcal{O}_F$. The results are stated in terms of the fundamental invariants associated to Jordan splittings of quadratic lattices.