Dear physics and foundations enthusiasts,

It is a pleasure to announce the fourth edition of our summer school Solstice of Foundations! It will take place at the University of Zurich, 16-20 June 2025.

We encourage you to send your PhD and Masters students to the school - they will return with a consolidated understanding of quantum foundations and an academic network of peers interested in the same topics.

This year's edition will focus on the importance of agents, relativity and correlations in the foundations of quantum mechanics.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. More on the programme below.

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Information and registration: http://foundations.squids.ch

15th May: Deadline for student support applications
20th May: Notification for student support applications
31st May: Registration deadline for in-person participants

Format: Hybrid. Both in-person and online participation are possible; in-person participation is encouraged.

Registration fee: CHF 150 for Masters students, 200 for PhD students, 250 non-students. Online attendance is free for students, but registration is mandatory. Students based in Zurich may volunteer to help with the school and have the fee waived.

Required background: The school is aimed at participants familiar with basics of quantum mechanics, and ideally introductory courses on quantum information theory.

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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

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May your well-being be strongly correlated with the wonderful Spring weather in Switzerland,

Lídia and Nuriya

PS: For questions, please contact Nuriya at foundations@squids.ch or her academic address in CC; Lídia is mostly non-signalling for the rest of the year.

 
.........

Dr. Lídia del Rio
Essentia Foundation Research Fellow for Quantum Information Theory
Institute of Physics, University of Zurich

I am on partial sick leave for the next few months, with limited working hours and access to email. For urgent queries, please contact my colleagues.