**Principal investigator:** Anđelo Samsarov

**PI's Host institution:** Ruđer Bošković Institute

**Project duration:** 01/03/2021 - 28/02/2025

## Project Summary

Black holes are predicted by the theory of general relativity as a result of a gravitational collapse of massive astrophysical objects. Among other interesting properties of black holes is a property that they exist in a state of constant arousal. Indeed, realistic black holes can never be fully described by their basic parameters, as they are always in a state of perturbation.

Black hole perturbation is followed by a ringdown phase which is dominated by quasinormal modes (QNM). These modes may provide key signature of the gravitational waves.

During the ringdown phase, black holes gradually relax from the initial perturbation by emitting gravitational waves and presumed Hawking radiation. Notably, the presence of a deformed spacetime structure may distort this signal. In order to account for such effects, in this project we plan to utilise the methods of noncommutative geometry (NC) in order to construct and devise appropriate physical models which would be able to deal with new circumstances. The aim of this project is to invetigate the scalar, Dirac, vector and gravitational QNMs resulting from perturbations of realistic 4-dimensional black holes in a presence of quantized spacetime. The same setting of NC geometry we plan to apply in studying the impact of deformation on both the symmetry and the dispersion relations as revealed in a propagation of high energy gamma rays resulting from distant gamma ray bursts.

## Project Members

## Marija Dimitrijević Čirić

IPB, Serbia

## Kumar Sankar Gupta

Saha Institute of Nuclear Physics, India

## Nikola Herceg

RBI, Croatia

## Tajron Jurić

RBI, Croatia

## Nikola Konjik

IPB, Serbia

## Salvatore Mignemi

Università degli Studi di Cagliari, Italy

## Ivica Smolić

University of Zagreb, Croatia

## List of Publications

**Black hole thermodynamics in the presence of nonlinear electromagnetic fields**

Ana Bokulić, Tajron Jurić, Ivica Smolić

Phys. Rev. D 103, 124059 (2021)

https://arxiv.org/abs/2102.06213

**Observables in Quantum Mechanics and the Importance of Self-adjointness**

Tajron Jurić

Universe 2022, 8, 129

https://arxiv.org/abs/2103.01080

**Nonlinear electromagnetic fields in strictly stationary spacetimes**

Ana Bokulić, Tajron Jurić, Ivica Smolić

Phys. Rev. D 105, 024067 (2022)

https://arxiv.org/abs/2111.10387

**Arrival time from the general theory of quantum time distributions**

Tajron Jurić, Hrvoje Nikolić

Eur. Phys. J. Plus 137 (2022) 5, 63

https://arxiv.org/abs/2107.08777

**Propagation of spinors on a noncommutative spacetime: equivalence of the formal and the effective approach**

Marija Dimitrijević-Ćirić, Nikola Konjik, Andjelo Samsarov

https://arxiv.org/abs/2208.06069

**Constraints on singularity resolution by nonlinear electrodynamics**

Ana Bokulić, Tajron Jurić, Ivica Smolić

Phys. Rev. D 106, 064020 (2022)

https://arxiv.org/abs/2206.07064

**Passive quantum measurement: Arrival time, quantum Zeno effect and gambler's fallacy**

Tajron Jurić, Hrvoje Nikolić

https://arxiv.org/abs/2207.09140

**Noncommutativity and logarithmic correction to the black hole entropy**

Kumar S. Gupta, Tajron Jurić, Anđelo Samsarov, Ivica Smolić

JHEP 02 (2023) 060

https://arxiv.org/abs/2209.07168

**Noncommutative correction to the entropy of charged BTZ black hole**

Tajron Jurić, Filip Požar

Symmetry 2023, 15(2), 417

https://arxiv.org/abs/2212.06496

## Event Organization

05-09 September 2022: Quantum aspects of Black Holes and Gravity, Zagreb, Croatia (A. Samsarov & T. Jurić)