Hirotaka Yoshino: Gallery


  • Marginally DTTSs in the Brill-Lindquist two-black-hole initial data

    In our recent work, we defined a new concept, a marginally Dynamically Transversely Trapping Surface (a marginally DTTS), to characterize strong gravity regions. A marginally DTTS is reduced to the photon sphere r=3M in the Schwarzschild spacetime. A marginally DTTS has close analogy with a marginally trapped surface (or, an apparent horizon), which is reduced to the horizon r=2M in the Schwarzschild spacetime.


    The Brill-Lindquist initial data is vacuum time-symmetric initial data with conformally flat spatial structure,

    .

    The equation for Ψ is reduced to the Laplace equation of a flat space, and if we choose the solution

    ,

    the initial data represent the system of two black holes momentarily at rest. Here are the pictures of marginally DTTSs in the initial data:




  • Marginally trapped surfaces (or, apparent horizons) in the Brill-Lindquist two-black-hole initial data

    For comparison, I show the pictures of marginally trapped surfaces in the same initial data. Similarity between marginally DTTSs and marginally trapped surfaces can be recognized.




  • Marginally DTTSs in the system of two black holes in a Majumdar-Papapetrou spacetime

    We also studied marginally DTTSs in the system of two black holes in the Majumdar-Papapetrou spacetime. The Majumdar-Papapetrou spacetime is a static spacetime with a metric,

    .

    Electromagnetic fields are present in this spacetime and the four-potential is given by

    .

    The equation for U is reduced to the Laplace equation of a flat space, and if we choose the solution

    ,

    the system reperesents two black holes, which are kept static due to balance between gravitational attractiive interaction and electromagnetic repulsive interaction.

    Here are pictures of marginally DTTSs in the system of two black holes in a Majumdar-Papapetrou spacetime.




  • See our paper arXiv:1909.08420[gr-qc] for details.





    Back to Hirotaka Yoshino homepage






    inserted by FC2 system