Measuring the spin parameter of kerr black holes and naked singularities

Kenta Hioki, Keiichi Maeda

    Research output: Chapter in Book/Report/Conference proceedingConference contribution

    Abstract

    The possibility that the existence of black holes as compact objects at the cores of galaxies has become high. The black hole is said to cast an apparent shape (or a shadow) as an optical appearance because of the strong gravitational field in the black hole itself. The apparent shape is of varied forms mainly depending on the spin parameter and the inclination angle of the object. In this paper, we investigate whether it is possible to determine the spin parameter and the inclination angle by observing the apparent shape, on the assumption that the intended compact object is the Kerr space-time. In particular, we define observables which definitely characterize the apparent shape. We find that one can estimate the spin parameter and the inclination angle of the Kerr black hole even when it is naked singularity, by measuring the observables. As a prerequisite, one needs only information of the mass of the object to say so. The result will become a realistic method which come a step closer to probe the Galactic centre using future advanced interferometers.

    Original languageEnglish
    Title of host publicationProceedings of the 18th Workshop on General Relativity and Gravitation in Japan, JGRG 2008
    Publication statusPublished - 2008
    Event18th Workshop on General Relativity and Gravitation in Japan, JGRG 2008 - Higashi-Hiroshima
    Duration: 2008 Nov 172008 Nov 21

    Other

    Other18th Workshop on General Relativity and Gravitation in Japan, JGRG 2008
    CityHigashi-Hiroshima
    Period08/11/1708/11/21

    Fingerprint

    naked singularities
    inclination
    gravitational fields
    casts
    interferometers
    galaxies
    probes
    estimates

    ASJC Scopus subject areas

    • Atomic and Molecular Physics, and Optics

    Cite this

    Hioki, K., & Maeda, K. (2008). Measuring the spin parameter of kerr black holes and naked singularities. In Proceedings of the 18th Workshop on General Relativity and Gravitation in Japan, JGRG 2008

    Measuring the spin parameter of kerr black holes and naked singularities. / Hioki, Kenta; Maeda, Keiichi.

    Proceedings of the 18th Workshop on General Relativity and Gravitation in Japan, JGRG 2008. 2008.

    Research output: Chapter in Book/Report/Conference proceedingConference contribution

    Hioki, K & Maeda, K 2008, Measuring the spin parameter of kerr black holes and naked singularities. in Proceedings of the 18th Workshop on General Relativity and Gravitation in Japan, JGRG 2008. 18th Workshop on General Relativity and Gravitation in Japan, JGRG 2008, Higashi-Hiroshima, 08/11/17.
    Hioki K, Maeda K. Measuring the spin parameter of kerr black holes and naked singularities. In Proceedings of the 18th Workshop on General Relativity and Gravitation in Japan, JGRG 2008. 2008
    Hioki, Kenta ; Maeda, Keiichi. / Measuring the spin parameter of kerr black holes and naked singularities. Proceedings of the 18th Workshop on General Relativity and Gravitation in Japan, JGRG 2008. 2008.
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