Welcome to Solstice of Foundations, a summer school series on quantum foundations. This year’s edition will be jointly hosted by the University of Zurich and Squids, from the 16th to the 20th of June 2025. The school provides a solid introduction to current approaches and problems within foundational research, and is tailored for junior researchers entering the field, like masters and PhD students, as well as postdocs transitioning from adjacent fields.
The 2025 edition will focus on the importance of agents, relativity and correlations in quantum foundations. This includes quantum reference frames, modelling observers as explicit physical systems, the motility of the Heisenberg cut, multi-agent paradoxes, and the role of the observer and boundaries in novel approaches to relativity and quantum gravity.
Lecturers
Exploring the foundations of physics
A resource-theoretical approach to non-classicality
Modelling agents in quantum theory and beyond
Multi-agent paradoxes
Quantum reference frames
From quantum information to quantum gravity
Boundaries and agents in quantum gravity
Programme
The school starts on Monday at 9:45 and ends on Friday before lunch (CEST). A detailed schedule will be published by mid-May.
Lectures take place in the centre campus of the University of Zurich. The school will be a hybrid event: all lectures will be streamed live, and the recordings will be publicly available after. We will have a Discord server to support in-person and online participants.
The school is aimed at participants familiar with basics of quantum mechanics, and ideally introductory courses to quantum information theory.
The school is structured in three thematic blocks:
1. Foundations of quantum physics
Introduction to foundations of quantum physics; different approaches to quantum foundations; Bell non-locality; contextuality.
These lectures will take place on Monday-Tuesday. Lecturers:
- Robert Spekkens, Perimeter Institute for Theoretical Physics, Canada
- David Schmid, Perimeter Institute for Theoretical Physics, Canada
2. Agents and paradoxes in physical theories
How to model observers as physical systems, in quantum theory and beyond; Wigner-friend scenarios; paradoxes that emerge when trying to combine the viewpoints of different observers; relation to contextuality; systems as subjective concepts.
These lectures will take place on Tuesday-Wednesday. Lecturers:
- Renato Renner, ETH Zurich, Switzerland
- Yìlè Yīng, Perimeter Institute for Theoretical Physics, Canada
2. From quantum reference frames to quantum gravity
Modelling quantum reference frames; physical objects as imperfect reference frames; frame transformations; the equivalence principle; spacial superpositions of masses and gravitational fields; introduction to quantum gravity; the role of boundaries and observers in quantum gravity.
These lectures will take place on Thursday-Friday. Lecturers:
- Anne-Catherine de la Hamette, IQOQI, Austria
- Flaminia Giacomi, ETH Zurich, Switzerland
- Daniele Oriti, Complutense University of Madrid
Important dates
All deadlines are at 23:59 AoE, all dates are in 2025.
- 8th April: Registration opens
- 15th May: Deadline for student support applications
- 20th May: Notification for student support applications
- 31st May: Registration deadline for in-person participants
- 16th-20th June: Solstice of Foundations 2025