Analog rotating black holes in a magnetohydrodynamic inflow

Sousuke Noda, Yasusada Nambu, Masaaki Takahashi

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)


We present a model of the analog geometry in a magnetohydrodynamic (MHD) flow. For the MHD flow with magnetic pressure-dominated and gas pressure-dominated conditions, we obtain the magnetoacoustic metric for the fast MHD mode. For the slow MHD mode, on the other hand, the wave is governed by the advective-type equation without an isotropic dispersion term. Thus, the "distance" perpendicular to the wave propagation is not defined, and the magnetoacoustic metric cannot be introduced. To investigate the properties of the magnetoacoustic geometry for the fast mode, we prepare a two-dimensional axisymmetric inflow and examine the behavior of magnetoacoustic rays which is a counterpart of the MHD waves in the eikonal limit. We find that the magnetoacoustic geometry is classified into three types depending on two parameters characterizing the background flow: analog spacetimes of rotating black holes, ultra spinning stars with ergoregions, and spinning stars without ergoregions. We address the effects of the magnetic pressure on the effective geometries.

Original languageEnglish
Article number104055
JournalPhysical Review D
Issue number10
Publication statusPublished - 2017
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy (miscellaneous)


Dive into the research topics of 'Analog rotating black holes in a magnetohydrodynamic inflow'. Together they form a unique fingerprint.

Cite this