My research in theoretical physics focuses on the questions on how to construct a quantum theory of gravity and how to unify the four fundamental forces of Nature.

Together with the mathematician Johannes Aastrup I have developed Quantum Holonomy Theory, which is a candidate for a non-perturbative and background independent theory of quantum gravity coupled to matter.

Other research topics, which I have worked on, are various aspects of non-commutative geometry and its relation to theoretical physics; various aspects of quantum field theory such as BRST and Batalin-Vilkovisky quantization of gauge theories; algebraic quantum field theory, topological field theories and supersymmetric Yang-Mills theory.