Spatial Route Dependence
If we place two observers (A and B) on opposite sides of a rotating black hole, both on the rotation plane, with the hole directly between them, and with both observers being the same height above the hole, then the effective gravitational differential between the A and B measured across the plane depends on the direction around the hole in which measurements are taken.
If light signals are exchanged around one side of the hole, in the equatorial plane, where the adjacent section of event horizon is moving roughly in the direction A→B, then frame-dragging effects should make it easier for light to move with the horizon's motion than against it, and the measurements should show B to be downhill of A.
If we repeat the exercise with light signals sent around the other side of the hole, the resulting anisotropy in the speed of light will now act in the opposite direction, and B will appear to be uphill of A.
Read more about this topic: Route Dependence
Famous quotes containing the words route and/or dependence:
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