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In the space between galaxies in the absence of matter, would time run faster than inside a galaxy? A black hole can slow time. Is there a cosmic opposite of that effect on time? Like the following question:
If time stood still at the event horizon of a black hole (wrt an inertial observer), is there a place where time would speed up in absence of mass (again, wrt an inertial observer)? If yes, What is the fastest time can get?