Exotic black holes

    Research output: Contribution to journalArticle

    19 Citations (Scopus)

    Abstract

    We study exotic black holes, which are new types of black holes obtained from unified theories. The exotic black holes we discussed here are classified into two; one is those with dilaton field, and the other contains non-Abelian "gauge" fields. We discuss their thermodynamical properties and evolutions. The farmer shows that the superstring predicts a critical dilaton coupling to U(1) field such that the Hawking radiation changes completely beyond the critical value and it diverges in the extreme limit. As a result, a naked singularity may appear at the end of evaporation process for models with larger coupling than the critical value. The second type of exotic black holes give non-trivial black holes, which have the first type of hair. Since some of them are stable, this can be regarded as counterexamples of no hair conjecture. The specific heat will change the sign a few times for some range of parameters. The fate of those black holes are as follows:(1) The unstable black holes will becomes the other stable ones including Schwarzschild black hole. (2) The neutral black holes with the "effective mass" of non-Abelian fields have the upper bound of the black hole mass and when the black hole evolves beyond this critical value, it shifts to more stable Schwarzschild black hole. If the black hole evaporates via the Hawking radiation, the stable particle will remain. (3) For the charged black hole such as monopole black hole, since the Reissner-Nordström black hole below some critical mass becomes unstable and there is no Schwarzschild black hole, the monopole black hole is a unique and stable black hole in some range of parameters. When the black hole gets the mass via accretion, it will become the Reissner-Nordström trivial black hole, while when it evaporates via the Hawking radiation, the stable regular monopole will remain.

    Original languageEnglish
    JournalJournal of the Korean Physical Society
    Volume28
    Issue numberSUPPL. 4
    Publication statusPublished - 1996

    Fingerprint

    monopoles
    hair
    radiation
    critical mass
    naked singularities
    evaporation
    specific heat
    shift

    ASJC Scopus subject areas

    • Physics and Astronomy(all)

    Cite this

    Exotic black holes. / Maeda, Keiichi.

    In: Journal of the Korean Physical Society, Vol. 28, No. SUPPL. 4, 1996.

    Research output: Contribution to journalArticle

    @article{3543e5a297ad42e0b58495c5ec075a0b,
    title = "Exotic black holes",
    abstract = "We study exotic black holes, which are new types of black holes obtained from unified theories. The exotic black holes we discussed here are classified into two; one is those with dilaton field, and the other contains non-Abelian {"}gauge{"} fields. We discuss their thermodynamical properties and evolutions. The farmer shows that the superstring predicts a critical dilaton coupling to U(1) field such that the Hawking radiation changes completely beyond the critical value and it diverges in the extreme limit. As a result, a naked singularity may appear at the end of evaporation process for models with larger coupling than the critical value. The second type of exotic black holes give non-trivial black holes, which have the first type of hair. Since some of them are stable, this can be regarded as counterexamples of no hair conjecture. The specific heat will change the sign a few times for some range of parameters. The fate of those black holes are as follows:(1) The unstable black holes will becomes the other stable ones including Schwarzschild black hole. (2) The neutral black holes with the {"}effective mass{"} of non-Abelian fields have the upper bound of the black hole mass and when the black hole evolves beyond this critical value, it shifts to more stable Schwarzschild black hole. If the black hole evaporates via the Hawking radiation, the stable particle will remain. (3) For the charged black hole such as monopole black hole, since the Reissner-Nordstr{\"o}m black hole below some critical mass becomes unstable and there is no Schwarzschild black hole, the monopole black hole is a unique and stable black hole in some range of parameters. When the black hole gets the mass via accretion, it will become the Reissner-Nordstr{\"o}m trivial black hole, while when it evaporates via the Hawking radiation, the stable regular monopole will remain.",
    author = "Keiichi Maeda",
    year = "1996",
    language = "English",
    volume = "28",
    journal = "Journal of the Korean Physical Society",
    issn = "0374-4884",
    publisher = "Korean Physical Society",
    number = "SUPPL. 4",

    }

    TY - JOUR

    T1 - Exotic black holes

    AU - Maeda, Keiichi

    PY - 1996

    Y1 - 1996

    N2 - We study exotic black holes, which are new types of black holes obtained from unified theories. The exotic black holes we discussed here are classified into two; one is those with dilaton field, and the other contains non-Abelian "gauge" fields. We discuss their thermodynamical properties and evolutions. The farmer shows that the superstring predicts a critical dilaton coupling to U(1) field such that the Hawking radiation changes completely beyond the critical value and it diverges in the extreme limit. As a result, a naked singularity may appear at the end of evaporation process for models with larger coupling than the critical value. The second type of exotic black holes give non-trivial black holes, which have the first type of hair. Since some of them are stable, this can be regarded as counterexamples of no hair conjecture. The specific heat will change the sign a few times for some range of parameters. The fate of those black holes are as follows:(1) The unstable black holes will becomes the other stable ones including Schwarzschild black hole. (2) The neutral black holes with the "effective mass" of non-Abelian fields have the upper bound of the black hole mass and when the black hole evolves beyond this critical value, it shifts to more stable Schwarzschild black hole. If the black hole evaporates via the Hawking radiation, the stable particle will remain. (3) For the charged black hole such as monopole black hole, since the Reissner-Nordström black hole below some critical mass becomes unstable and there is no Schwarzschild black hole, the monopole black hole is a unique and stable black hole in some range of parameters. When the black hole gets the mass via accretion, it will become the Reissner-Nordström trivial black hole, while when it evaporates via the Hawking radiation, the stable regular monopole will remain.

    AB - We study exotic black holes, which are new types of black holes obtained from unified theories. The exotic black holes we discussed here are classified into two; one is those with dilaton field, and the other contains non-Abelian "gauge" fields. We discuss their thermodynamical properties and evolutions. The farmer shows that the superstring predicts a critical dilaton coupling to U(1) field such that the Hawking radiation changes completely beyond the critical value and it diverges in the extreme limit. As a result, a naked singularity may appear at the end of evaporation process for models with larger coupling than the critical value. The second type of exotic black holes give non-trivial black holes, which have the first type of hair. Since some of them are stable, this can be regarded as counterexamples of no hair conjecture. The specific heat will change the sign a few times for some range of parameters. The fate of those black holes are as follows:(1) The unstable black holes will becomes the other stable ones including Schwarzschild black hole. (2) The neutral black holes with the "effective mass" of non-Abelian fields have the upper bound of the black hole mass and when the black hole evolves beyond this critical value, it shifts to more stable Schwarzschild black hole. If the black hole evaporates via the Hawking radiation, the stable particle will remain. (3) For the charged black hole such as monopole black hole, since the Reissner-Nordström black hole below some critical mass becomes unstable and there is no Schwarzschild black hole, the monopole black hole is a unique and stable black hole in some range of parameters. When the black hole gets the mass via accretion, it will become the Reissner-Nordström trivial black hole, while when it evaporates via the Hawking radiation, the stable regular monopole will remain.

    UR - http://www.scopus.com/inward/record.url?scp=0030495632&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=0030495632&partnerID=8YFLogxK

    M3 - Article

    AN - SCOPUS:0030495632

    VL - 28

    JO - Journal of the Korean Physical Society

    JF - Journal of the Korean Physical Society

    SN - 0374-4884

    IS - SUPPL. 4

    ER -