Building cryptography secure against quantum computers

The cryptography that keeps the Internet secure today has an expiration date. When a large enough quantum computer is built, these systems can be broken efficiently. In response to this looming threat, the field of post-quantum cryptography aims to find new quantum-safe replacements. During his PhD studies, Marius A. Årdal researched post-quantum signature schemes based on hard mathematical problems from lattices and isogenies. His work focused both on constructing new cryptographic systems and developing rigorous methods for analyzing their security. 

The PhD study was completed at the Department of Computer Science, Faculty of Natural Sciences, Aarhus University.

This summary was prepared by the PhD student.

Time: Thursday, 15 October 2026 at 14:00.
Place: Building 5342, room 333, Department of Computer Science, Aarhus University, Åbogade 34, 8200 Aarhus N.
Title of PhD thesis: Towards Provable Security in a Post-Quantum World
Contact information: Marius André Årdal, e-mail: maardal@cs.au.dk, tel.: +45 42725436
Members of the assessment committee:
Senior research scientist Benjamin Smith, INRIA and Ecole Polytechnique, France
Lecturer Ngoc Khanh Nguyen, Department of Informatics at King’s College London, UK
Associate Professor Chris Schwiegelshohn (chair), Department of Computer Science, Aarhus University, Denmark
Main supervisor: Associate Professor Diego F. Aranha, Department of Computer Science, Aarhus University, Denmark
Language: The PhD dissertation will be defended in English

The defence is public.
The PhD thesis is available for reading at the Graduate School of Natural Sciences/GSNS, Ny Munkegade 120, building 1521, 8000 Aarhus C