The Fourth Hermann Minkowski Meeting on the Foundations of Spacetime Physics, organized by the Minkowski Institute (Montreal), will be held in the famous Black Sea resort Albena (near Varna) from 15th to 18th September 2025: https://minkowskiinstitute.com/meetings/2025/ The Fourth Minkowski Meeting will again provide a relaxing environment and a friendly and stimulating atmosphere for physicists, mathematicians and historians of physics to report on their latest results in any research area related to the physics of spacetime and to exchange ideas on open questions in fundamental physics. Starting from this meeting the scientific organising committee also invites talks and encourages participation in the panel discussions on two research directions (for details see https://minkowskiinstitute.com/meetings/2025/call.html): - Whether gravitational phenomena can be fully accounted for by the non-Euclidean geometry of spacetime without the need to assume that gravitation is a physical interaction. - Whether spacetime physics can naturally explain both macroscopic (including gravitational) phenomena and microscopic (quantum) phenomena. Abstracts should be emailed to minkowski2025@minkowskiinstitute.com <mailto:minkowski2025@minkowskiinstitute.com> by 1 June 2025. They will be reviewed and notification of acceptance will be sent by 15 June 2025. Scientific Organizing Committee: Abhay Ashtekar (Penn State University) Valeria Ferrari (University of Rome "La Sapienza") David Garfinkle (Okland University) Robert Geroch (University of Chicago) James Isenberg (University of Oregon) Claus Kiefer (University of Cologne) Vesselin Petkov (Minkowski Institute, Montreal) Carlo Rovelli (Rotman Institute of Philosophy) Nick Woodhouse (University of Oxford, Clay Mathematics Institute) Vesselin Petkov One of the founders and current director of Minkowski Institute Montreal, Canada https://minkowskiinstitute.com <https://minkowskiinstitute.com/> vpetkov@minkowskiinstitute.com <mailto:vpetkov@minkowskiinstitute.com> Personal page: https://vesselinpetkov.com/