Sounds specific to dying engines,
picked locks,
or waves lapping at the surface just above your head;
The feeling of the earth crumbling below you,
the tremor caused by a far-off explosion,
or the way black holes will lure anything into their grasps.
The way any noise can make you jump,
the mention of someone causing your breathing to quicken, your pupils to dilate, or your hair to stand on end.
Knowing that there's no solution.