What is the space-time medium?
According to this answer: "... fields are a fundamental part of the universe." Then why do we describe a gravity as being depressions in space-time?
And why don't we describe weak, strong, or electromagnetic forces as such?
Have we actually proved that there is no substance that makes space-time?
Also is there a difference between the ideas of aether and quantum foam?
closed as too broad by ACuriousMind♦, lemon, Qmechanic♦ Mar 27 '16 at 15:11
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