Kaj Börjeson. Photo: Stockholm University.
Kaj Börjeson. Photo: Stockholm University.

Kaj Börjeson’s research project consists of two parts, each of which studies algebraic structures; structures that can help describe spaces which are difficult to visualize. The project’s main theme revolves around algebraic methods originally developed for computations in quantum field theories.

The first part deals with free loop spaces. Such spaces can be formed from all closed curves in a geometric space. An example of such a space could be rubber bands stretched around a sphere. In a free loop space, these bands can be placed in any direction on the surface of the sphere.

Infinite dimensional loop spaces can be studied with the help of algebraic topology, a branch of mathematics with applications spanning from physics and computer science to health sciences and economics. Algebraic topology can be used to describe particle motions in quantum mechanics, as well as to create three-dimensional images in computer tomography.

The goal of the second part of the project is to find general properties of special functions, differential operators, which are invariant even under a change of coordinate system. Studying phenomena independent of the choices made in advance, such as pre-chosen coordinate systems, is of great interest to both mathematicians and physicists.

In summary, the goal of the research project is to create and study new algebraic structures and use them to solve outstanding problems in topology, geometry, and physics.