4 ms·
> but "now" is the collection of events that currently affect us. Just to see if I understand what you’re saying… So a hypothetical photon from the big bang (
by ckcheng 19d ago
> but "now" is the collection of events that currently affect us.
Just to see if I understand what you’re saying…
So a hypothetical photon from the big bang (era?) gets observed now means the big bang is happening now?
A dinosaur decays to bones and now gets observed means the dinosaur died just now - not that it died millions of years ago?
(Dinosaur = photon from a star or something. Decay = red shift. Or a real dinosaur— guess it’s the same now.)
- drfloyd51 19d ago“Now” is weird. It doesn’t exist in a cosmic sense. Check out book “the order of time”.
- dotancohen 19d ago> So a hypothetical photon from the big bang (era?) gets observed now means the big bang is happening now? Yes. More specifically, the big bang would be happening now, at the location from where we perceive that photon. Hey, this stuff is not intuitive. However the early universe absorbed all the big bang photons. The furthest back we can observe photons from is the CMB. And yes, the phase change is happening now, there... Complicated by the Hubble expansion of course. > A dinosaur decays to bones and now gets observed means the dinosaur died just now - not that it died millions of years ago? No, that is incorrect. But you already knew that. Analogies don't work for light and for time and for relativity - it is too different from our everyday experiences for analogies to hold.
- ckcheng 18d ago[flagged]