GeomGravX: 10 Years of Geometric Foundations of Gravity and eXtensions (in Tartu)

Session

Thursday Parallel A

2 Jul 2026, 13:30

A106 (Physicum, University of Tartu)

102. Diego Molina: Maxwellian gravity and the cosmological constant

02/07/2026, 13:30

1

Inspired by the power of algebraic expansions to reveal hidden structures in physical theories, we explore the role of infinite semigroup expansions in the context of gravitational theories, focusing on the derivation of Maxwellian gravity and its relation to the cosmological constant. By systematically extending the symmetry structure of AdS, we unveil a natural path leading from Poincaré...

103. Justin Feng: Event horizon termination and the emergence of Lorentz signature

02/07/2026, 13:55

1

In this talk, I describe in detail how one might understand the termination of the event horizon of a black hole in terms of of quasiregular singularity characterized by points possessing two future-directed light cones and two past-directed light cones (in fact this spacetime is conformal to a region of the 1+1 trousers spacetime). I then discuss Euclidean signature shift-symmetric...

104. Philip Schwartz: Weyl-type theorems in Galilei and Carroll geometry

02/07/2026, 14:20

1

A classic theorem of Weyl (1921) states that a Weyl metric—a natural generalisation of a pseudo-Riemannian metric—is uniquely determined by its conformal and projective structures. This theorem forms the basis for the famous Ehlers–Pirani–Schild (EPS) axiomatic reconstruction (1972) of Lorentzian spacetime structure from light rays and the worldlines of massive particles.
An equivalent...

105. Pietro Isaia: A Variational Framework for Linearised Theories

02/07/2026, 14:45

The usual approach to perturbation theory presents some mathematical flaws. For instance, when studying gravitational waves (GW) around a Minkwoski background, one usually imposes the weak-field limit, requiring the spacetime metric to be the Minkowski metric plus a small perturbation. However, the bundle of Lorentzian metrics is neither linear nor affine; thus, the addition operation is not...