Quote:
Originally Posted by Sephiroth
Chris wrote:
OK - I can buy that. If we could be still while our galaxy was moving in space (not "space-time - what is that?) then the receding galaxy would not be moving away from us faster than light. That is a thought experiment because we don't know (someone might) how to become still/motionless in space.
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If you’ve not come across the term ‘spacetime’ then you haven’t a cat in hell’s chance of understanding any of the issues you’re raising here (not that I’m presenting myself as an expert either, you understand).
In Einsteinian physics, space and time are not separate concepts. Time is measured as a fourth dimension of space. A four-dimensional spacetime model is essential for understanding relativistic effects, which are not mere mathematical oddities but have real-world applications (in the operation of GPS for example).