Sjene crnih rupa

master's thesis

• Title (english): Black hole shadows
• Author: Laura Busak
• Mentor: Ivica Smolić (mentor)
• Committee member: Ivica Smolić (predsjednik povjerenstva)
• Committee member: Maro Cvitan (član povjerenstva)
• Committee member: Nikola Poljak (član povjerenstva)
• Committee member: Davor Horvatić (član povjerenstva)
• Committee member: Matko Glunčić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Physics); Zagreb
• Defense date and country: 2024-09-18, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract

Premda je teorijsko proučavanje crnih rupa tema vezana za opću teoriju relativnosti još od ranih dana, tek nedavni promatrački uspjesi Event Horizon Telescope kolaboracije omogućili su direktno opažanje njihova izgleda. U ovom radu napravljen je pregled analitičkih studija vizualnih profila crnih rupa, poznatih pod nazivom ”sjena”, konkretno za statični sferno simetrični i Kerrov slučaj. Predstavljena je fizikalna pozadina pojave sjene, a zatim i razloženi osnovni koraci potrebni za njezinu konstrukciju, uz osvrt na dvije klase degeneracije sjene predstavljene u literaturi. Metodologija pronalaska oblika i veličine sjene oprimjerena je za nekoliko različitih metrika crnih rupa. Usporedbom slučajeva idealne sferne i ravne pozadine istaknuta je razlika između sjene i vizualnih efekata koji su posljedica samo konkretne raspodjele okolnih izvora elektromagnetskog zračenja.

Abstract (english)

Although black holes have been theoretically studied since the early days of the general theory of relativity, only recently have the observational successes of the Event Horizon Telescope collaboration made it possible to directly observe them. We provide an overview of current analytical studies of the visual appearance of black holes, also known as black hole shadows. We examine the shadows of spherically symmetric, static black hole spacetimes, as well as the Kerr spacetime. We explore the physical background of the phenomenon, explain the basic steps necessary to construct the shadow, and briefly review two shadow degeneracy classes presented in the literature. We derive the size of the shadow and show how the methodology may be used on the examples of several black hole spacetimes. Finally, we highlight the fundamental differences between the shadow and the visual effects of the specific distribution of the surrounding sources of electromagnetic radiation by comparing two idealized cases for a Schwarzschild black hole: a uniformly bright spherical background and an infinite uniformly bright planar background.

• Keywords: sjene crnih rupa; fotonske orbite; efekt gravitacijske leće; Schwarzschildovo prostorvrijeme; jedinstvenost sjena crnih rupa
• Keywords (english): black hole shadows; photon orbits; gravitational lensing; Schwarzschild spacetime; black hole shadow uniqueness
• Language: croatian
• URN:NBN: urn:nbn:hr:217:971428
• Study programme: Title: The University Integrated Undergraduate and Graduate Programme in Physics; Research Physics; specializations in: Research Physics; Course: Research Physics; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: sveučilišni magistar fizike (sveučilišni magistar fizike)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2025-01-31 09:45:43