Normed modules, integral sequences, and integrals with variable upper limits
Miantao Liu, Yu-Zhe Liu, Shengda Liu
TL;DR
The article develops a categorification framework for the Lebesgue integral with variable upper limits using normed modules over finite-dimensional algebras and the A^p_Lambda category, culminating in a construction of integral partial ordered sets and a pivotal pmb Game morphism. It proves that the induced images form Lambda-modules and that the pmb Game^natural restricted to Im(+) yields a Lambda-epimorphism, enabling an addition law for integrals with variable upper limits. The authors present two key applications: a categorification of basic elementary functions including (anti-)trigonometric and logarithmic/exponential functions, and a novel representation-theoretic approach to the global dimensions of gentle algebras via multiple integrals and Lebesgue-Stieltjes measures. The work connects category theory, functional analysis, and representation theory to yield new insights into categorified integrals, with potential implications for differential/integral equations and algebraic invariants of gentle algebras.
Abstract
This paper provides a new categorification of the Lebesgue integral with variable upper limits by using normed modules over finite-dimensional $\Bbbk$-algebras $\mathitΛ$ and the category $\mathscr{A}^p_{\mathitΛ}$ associated with $\mathitΛ$. The integration process is redefined through the introduction of an integral partially ordered set and an abstract integral with variable upper limits. Finally, we present two important applications: (1) the categorification of basic elementary functions, including (anti-)trigonometric and logarithmic functions, and (2) a new approach for characterizing the global dimensions of gentle algebras.
