J 2024

Shadows of Kerr-de Sitter naked singularities

STUCHLÍK, Zdeněk and Daniel CHARBULÁK

Basic information

Original name

Shadows of Kerr-de Sitter naked singularities

Authors

STUCHLÍK, Zdeněk (203 Czech Republic, belonging to the institution) and Daniel CHARBULÁK (203 Czech Republic, belonging to the institution)

Edition

Physical Review D, 2024, 2470-0010

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10308 Astronomy

Country of publisher

United States of America

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

URL

Impact factor

Impact factor: 5.000 in 2022

Organization unit

Institute of physics in Opava

DOI

http://dx.doi.org/10.1103/PhysRevD.109.064008

UT WoS

001196566600007

Keywords in English

M87 event horizon; telescope results VI;black-hole;motion;field;dust;extraction;particles;signature;energy

Tags

RIV25

Tags

International impact, Reviewed
Změněno: 20/1/2025 13:47, Mgr. Pavlína Jalůvková

Abstract

V originále

We present a classification of Kerr-de Sitter spacetimes based on the presence of horizons, ergospheres, and the characteristics of photon motion. We utilize the concept of local escape cones for isotropically radiating point sources to create shadows of the Kerr-de Sitter naked singularities within a class containing astrophysically relevant parameters. For completeness, we also consider in the construction photons entering the region of negative radii of the naked singularity spacetimes. The shadow construction is associated with two astrophysically significant families of local reference frames (or local observers). The first family represents locally nonrotating frames that, near the so-called static radius in Kerr-de Sitter spacetimes, exhibit characteristics similar to those of static observers at large distances in asymptotically flat spacetimes. The second family involves radially escaping geodesic frames, which are suitable for constructing the shadow near the cosmological horizon of Kerr-de Sitter spacetimes. We explore how the aberration effect, caused by the motion of free observers due to the repulsive influence of the cosmological constant, modifies the shadow in comparison to those related to stationary locally nonrotating observers.
Displayed: 12/2/2025 23:31