OBAVIJEST
NIKOLA HERCEG
održat će znanstveni kolokvij (doktorski seminar) iz Fizike elementarnih čestica pod naslovom
Black hole perturbation theory in noncommutative spacetime
Black holes are not perfectly quiet objects – when perturbed, they “ring” like a bell. These vibrations are known as quasinormal modes (QNMs), and they form a key part of the gravitational waves observed during black hole mergers. Since the first detection of gravitational waves in 2015, there has been intense interest in using QNMs as a kind of spectroscopy: by analyzing the frequencies of the “ringdown,” it becomes possible to test whether Einstein’s theory of general relativity remains exact, or whether signatures of new physics emerge.
In this thesis, the behavior of these black hole vibrations is studied in a noncommutative spacetime, where the coordinates of spacetime no longer commute – an idea motivated by approaches to quantum gravity. The analysis is carried out within a mathematical framework based on Hopf algebras and Drinfeld twists, which provide a systematic way to deform spacetime symmetries.
Equations governing black hole perturbations are derived in this setting, and the corresponding QNM spectra are computed using several complementary approximation methods. The results indicate novel physical effects compared to classical general relativity, including a smeared black hole horizon and a breaking of the usual symmetry between different types of perturbations. Such features could, in principle, leave observable imprints in future gravitational wave data, offering a potential probe of quantum gravitational effects.
Seminar će se održati u petak 19. rujna 2025. godine u 14:15 sati u predavaonici F-201 na Fizičkom odsjeku Prirodoslovno-matematičkog fakulteta.
Pozivaju se studenti doktorskog studija Fizike, smjer Fizika elementarnih čestica da prisustvuju seminaru, ako nisu spriječeni.
Voditelj smjera
Izv. prof. dr. sc. Maro Cvitan, v. r.
Pristupačnost
