Strict $K$-monotonicity and $K$-order continuity in symmetric spaces

TL;DR

This paper explores strict $K$-monotonicity and $K$-order continuity in symmetric spaces, establishing connections with measure convergence and characterizing $K$-order continuity via fundamental functions.

Contribution

It provides new insights into the geometric structure of symmetric spaces, linking strict $K$-monotonicity with measure convergence and characterizing $K$-order continuity.

Findings

Connection between strict $K$-monotonicity and measure convergence.

Characterization of $K$-order continuity using fundamental functions.

Resolution of the problem relating $K$-order continuity points to embeddings into $L^1$.

Abstract

This paper is devoted to strict $K$- monotonicity and $K$-order continuity in symmetric spaces. Using the local approach to the geometric structure in a symmetric space $E$ we investigate a connection between strict $K$-monotonicity and global convergence in measure of a sequence of the maximal functions. Next, we solve an essential problem whether an existence of a point of $K$-order continuity in a symmetric space $E$ on $[0,\infty)$ implies that the embedding $E\hookrightarrow{L^1}[0,\infty)$ does not hold. We finish this article with a complete characterization of $K$-order continuity in a symmetric space $E$ that is written using a notion of order continuity under some assumptions on the fundamental function of $E$.