A representative of the College of Natural Sciences and Astronomy at Nicolaus Copernicus Superior School, Dr. Miljenka Čemeljić, took part in the 26th edition of the RAGtime scientific workshop, held in Opava, Czech Republic. The conference, which has been organized since 1999 by the Relativistic Astrophysics Group (RAG) at the Institute of Physics of Silesian University in Opava, provides a unique forum for discussing current problems in relativistic astrophysics.
RAGtime workshop
The 26th edition of the RAGtime workshop was held on December 9-13, 2024, in a hybrid mode. The workshop focused on the problems of relativistic astrophysics, mainly in the context of the physics of black holes and neutron stars. Considerable attention was given to confronting theoretical models with the latest observations made in both electromagnetic and gravitational waves. Important topics also included astrophysical effects in strong gravity in the presence of external magnetic fields and current problems of accretion theory.
During his talk, Dr. Čemeljić presented new results of numerical simulations on naked singularities. Theoretical models of such objects were developed in parallel with the General Theory of Relativity more than 100 years ago, but interest in them has increased again in the context of observations of supermassive black holes in the center of the M87 galaxy and the Milky Way by the Event Horizon Telescope collaboration. Although it is most likely that these are indeed black holes, there is a theoretical possibility that the observed objects could be naked singularities.
The paper presented by our researcher is the first publication presenting the results of numerical simulations using a pseudo-Newtonian potential. This approach allows easier analysis of naked singularities, speeding up and improving numerical simulations. These simulations preserve the sphere of zero gravity, which in the case of naked singularities is located at a certain distance from the singularity and potentially allows observation of the interior of such objects. In one of the models presented at the conference, the sphere in which matter can be at rest was marked with a dashed black line; inside it, gravity is repulsive.
