The upcoming talk
At the next session of the TCS,
on the 25th of February 2026,
at 2:15 – 3:15 p.m. CET / 3:15 – 4:15 p.m. EET
Mikołaj K. Korzyński
(CFT PAN, Warszawa)
shall talk about
“Weighing spacetime along the line of sight using
times of arrival of electromagnetic signals“.
Abstract
I will present a method of determining the mass density along the line of sight using variations of times of arrival of electromagnetic signals, as measured by two ensembles of free falling, precise clocks. The whole set-up may be considered a type of an extended gravitational compass, i.e. a device measuring directly the spacetime curvature using an ensemble of communicating clocks. I will also discuss the geometric interpretation of this measurement.
(All seminar talks are given on the online zoom platform. Unless requested otherwise by the speaker or required by the circumstances, and then specifically indicated in the announcement, the talks consist of two halves, 45 minutes each, separated by a 15-minute break. The web link for every session is circulated via the TCS mailing list. In order to be enlisted, please contact the Organisers.)
Calendar 2025/2026
| Date | Speaker (affiliation) | Title (with a link to the slides, whenever available) |
| October 15th, 2025 | Athanasios Chatzistavrakidis (Ruđer Bošković Institute, Zagreb) | Basic curvature tensors in geometry and physics |
| October 29th, 2025 | Martha Valentina Guarín Escudero (Charles University, Faculty of Mathematics and Physics, Prague) | Fedosov connections and L∞-algebras associated to dg-manifolds |
| November 12th, 2025 | Marcin Piątek (Instytut Fizyki, Uniwersytet Szczeciński) | Geometric Foundations of Celestial Amplitudes |
| December 3rd, 2025 | Jakub R. Filipek (WFUW, Warszawa) | Twisted Abelian Differential Cohomology and Weakly Abelian Lie Groups |
| December 17th, 2025 | Rafał R. Suszek (KMMF, WFUW) | Stacky Dynamics in the Shadows of Principaloid Bundles |
| January 13th, 2026 | Nikita Nekrasov (SCGP, Stony Brook, New York) | Geometry of relativistic hydrodynamics I |
| January 14th, 2026 | Nikita Nekrasov (SCGP, Stony Brook, New York) | Geometry of relativistic hydrodynamics II |
| February 18th, 2026 | Cristian Ortiz (IME-USP, São Paulo) | Morita equivalence of Lie groupoids |
| February 25th, 2026 | Mikołaj Korzyński (CFT PAN) | Weighing spacetime along the line of sight using times of arrival of electromagnetic signals |
| March 11th, 2026 | ||
| March 25th, 2026 | ||
| April 1st, 2026 | Gaëtan Borot (Institut für Mathematik, Humboldt-Universität zu Berlin) | Large N expansions for random partitions via Nekrasov equations |
| April 8th, 2026 | ||
| April 22nd, 2026 | ||
| May 6th, 2026 | ||
| May 20th, 2026 | ||
| June 3rd, 2026 | ||