In special relativity we have the velocity 'u', being the difference in speed between two objects, from which we work out time dilation, length contraction etc.(adsbygoogle = window.adsbygoogle || []).push({});

But if those objects are separated by some expanding space, but not moving with respect to that space, is there still the dilation effect?

What if both moved towards each other at the same speed as the space expanded between them, so the net effect what they weren't moving with respect to each other? Would there be no time dilation etc then?

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# Does expanding space affect time dilation etc?

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