# On the topological structure of the Hahn field and convergence of power series

## TL;DR

This paper explores the topological properties of the Hahn field, focusing on various vector topologies and establishing a convergence criterion for power series similar to that in the Levi-Civita field.

## Contribution

It introduces and compares different vector topologies on the Hahn field and establishes a convergence criterion for power series within this framework.

## Key findings

- Identification of the weakest vector topology similar to the Levi-Civita field's weak topology
- Comparison of various vector topologies on the Hahn field
- A convergence criterion for power series in the Hahn field

## Abstract

In this paper, we study the topological structure of the Hahn field whose elements are functions from the additive abelian group of rational numbers to the real numbers field, with well-ordered support. After reviewing the algebraic and order structures of the Hahn field, we introduce different vector topologies that are induced by families of semi-norms and all of which are weaker than the order or valuation topology. We compare those vector topologies and we identify the weakest one whose properties are similar to those of the weak topology on the Levi-Civita field. In particular, we state and prove a convergence criterion for power series that is similar to that for power series on the Levi-Civita field in its weak topology