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Tag Archives: speed of light

superluminal expansion [Q&A]

Atul of Canara College asks, is it true that the Universe is expanding at a speed greater than light speed? And if so, does that not conflict with Relativity? Yes, but no. And no. Yes, the Universe is expanding, but there is no single speed that characterizes that expansion. However, two objects separated by a […]

lookback time [Q&A]

Rakshit of Vidyodaya Public School asks, is it true that the farther we see into space, we are seeing further back in time? Yes, because of the limit imposed by the speed of light. When we see something now, we see the photons that were emitted by the object and that took some time getting […]