Stefan Weigert

Profile

Biography

I have been a Reader in Mathematical Physics at the University of York since 2005.

In the early 1980s I studied physics at RWTH Aachen in Germany. I was so impressed by a wonderful series of lectures given by Nico van Kampen, who was visiting from the Universiteit Utrecht in the Netherlands, that I decided to do my final year (diploma) thesis under his supervision. After an enjoyable and formative year in Utrecht, I moved to Switzerland in 1986 to study for a doctorate with Harry Thomas at the University of Basel.

I stayed in Basel for a few more years as a post-doc, followed by a year with Robert Littlejohn at the Lawrence Berkeley Laboratory in California, before completing my Habilitation and becoming a Privatdozent in 1996. I then joined Hans Beck's group at the University of Neuchâtel (Switzerland) as a Swiss National Science Foundation fellow, working closely with Anatole Amiet. In 2001 I took up my first permanent post in the Department of Mathematics at Hull.

Departmental roles

• Mathematics and Philosophy: Programme Leader (since 2021/22)
• Departmental Ethics representative (since 2022/23)
• Member of the Departmental Sustainability Committee (since 2022/23)

Research

Overview

Mathematical Physics

Ever since my undergraduate days, I have been fascinated by quantum theory. Indeed, most of my research has been in areas of (non-relativistic) quantum mechanics, such as quantum information and the foundations of quantum theory. In recent years I have worked on Gleason's theorem, uncertainty relations, mutually unbiased bases, PT symmetry and quantum state reconstruction.

Current and former PhD students

Currently, Alistair Mansfield is working on general probabilistic theories with space-time symmetries. Vincenzo Fiorentino is studying a version of quantum theory in which the effect of performing measurements on quantum states has been modified, and Adam Beales is exploring the properties of mutually unbiased bases for continuous variables. Laurens Walleghem, jointly supervised with Matt Pusey, is investigating modern versions of a paradox initially introduced by E. Wigner.

Vicky Wright and I studied Gleason-type theorems and Hilbert space formulations of models with post-quantum correlations. Spiros Kechrimparis and I systematically derived new preparational uncertainty relations for quantum systems with one or more continuous variables. Steve Brierley, Dan McNulty and I shed light on the existence problem for complete sets of mutually unbiased bases, mostly in dimension six.

Literary studies

I am also interested in the history of science and epistemological issues, especially the rhetorical strategies used by the authors of scientific texts. In some papers I have studied specific aspects of grammar and style that feature prominently in the writings of Georg Christoph Lichtenberg, an 18th-century German physicist known for his witty aphorisms.

Research group(s)

Mathematical Physics and Quantum Information Research Group

Available PhD research projects

If you would like to write a PhD thesis dealing with fundamental questions in quantum theory, you are welcome to contact me. Project areas include uncertainty relations, mutually unbiased bases, and generalised probabilistic theories with post-quantum correlations. I am also open to discussing the supervision of other topics in quantum information and foundations of quantum theory.

Supervision

Current Research Students

• Adam Beales - adam.beales@york.ac.uk
• Vincenzo Fiorentino - vincenzo.fiorentino@york.ac.uk
• Alistair Mansfield - alistair.mansfield@york.ac.uk
• Laurens Walleghem - laurens.walleghem@york.ac.uk