Putting aside gravity, if there were some way to stretch and twist spacetime, what effect would that have on the matter inside the volume? Say we were talking about a part of spacetime that enclosed the earth, would the earth itself be stretched and twisted? Also, wouldn't a ruler I used be warped in the same way as any object that it might be used to measure and therefore there would be no detectable effect? Also, if I where able to expand spacetime (which is what I understand inflation to be) would the matter inside it similarly expand? E.g. Say there were 2 objects inside the expanding spacetime, would they get farther apart and also become larger themselves?