Bridging high and low energies in search of quantum gravity - 2025 Cost Action CA23130 First Annual Conference

Session

WG1 High Energy QG Theory 3

9 Jul 2025, 11:05

Amphithéâtre Charpak (LPNHE)

43. Simulations and the Resulting Spectra for Reactions in Astrophysical Electromagnetic Cascades with Lorentz Invariance Violation

Andrey Saveliev (Immanuel Kant Baltic Federal University)

09/07/2025, 11:05

Oral contribution

Lorentz Invariance Violation (LIV) is a feature of several quantum gravity models in which Lorentz symmetry is broken at high energies, leading to potential changes in particle behavior and interactions. In this study, we present simulations (and the corresponding methods) of the propagation of astrophysical electromagnetic cascades with LIV, which in particular results in new types of...

49. The regularization of spacetime singularities

Vania Vellucci (University of Southern Denmark)

09/07/2025, 11:25

Oral contribution

Spacetime singularities are often regarded as evidence of the fundamental incompleteness of General Relativity (GR). It is generally expected that a quantum theory of gravity will prevent their formation. In this talk, I will explore various proposed 'regular' geometrical structures that could effectively replace classical singularities as the end states of gravitational collapse. I will...

52. Revisiting noncommutative spacetimes from the relative locality principle

José Javier Relancio Martínez (University of Burgos)

09/07/2025, 11:45

Oral contribution

Relativistic deformed kinematics leads to a loss of the absolute locality of interactions. In previous studies, some models of noncommutative spacetimes in a two-particle system that implements locality were considered. In this talk, we present a characterization of the Poisson-Lie algebras formed by the noncommutative space-time coordinates of a multi-particle system and Lorentz generators as...

44. Beyond Standard Cosmology: New Statistical Approaches to Lorentz Invariance Violation

Denitsa Staicova (INRNE, Bulgarian Academy of Sciences)

09/07/2025, 12:05

Oral contribution

The Hubble tension poses serious questions not only to cosmology, but also to fundamental physics. In this talk, we will summarize our results so far as to how combining Lorentz Invariance Violation (LIV) time-delay measurements from gamma-ray bursts (GRBs) with standard cosmological datasets (BAO, SN) reveal interdependence between quantum gravity phenomena and cosmological models, how the...

47. Time Dilation in Planck-scale-deformed Special Relativity

Pietro Pellecchia

09/07/2025, 12:25

Oral contribution

I will show how to derive finite boost transformations within the theory of Deformed Special Relativity based on the bicrossproduct-basis κ-Poincarè Hopf algebra.
This enables to establish key properties of the theory, such as worldline covariance and the spacetime metric.
These results allow the derivation of a Planck-scale-modified time dilation factor, which may be relevant for quantum...

39. Operator dressing & proto-gauge theory from quantum mereology

Dr Oliver Friedrich (Ludwig-Maximilians-Universität München)

09/07/2025, 12:45

Oral contribution

Instead of quantizing a classical phase space, the program of quantum mereology takes abstract Hamiltonian operators defined in some Hilbert space as its starting point, and investigates under which conditions such a setting induces semi-classical dynamics. We advance this program by studying the emergence of entire sets of degrees-of-freedom from random Hamiltonians. We show that these...