Figure 14

Figure 14: This figure shows the pretracking surfaces at various times in a spiraling binary black hole collision, projected into the black holes’ orbital plane. (The apparent slow drift of the black holes in a clockwise direction is an artifact of the corotating coordinate system; the black holes are actually orbiting much faster, in a counterclockwise direction.) Notice how, even well before the common apparent horizon first appears (t = 16.44 mADM, bottom right plot), the rΘ pretracking surface is already a reasonable approximation to the eventual common apparent horizon’s shape. Figure reprinted with permission from [135]. © 2005 by the American Physical Society.