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Question: I think this is a curious question!! Is it a common misconception that recession velocities cannot exceed the speed of light? Here is my view on the topic. A common misconception is that the expansion of the universe cannot be faster than the speed of light. Since Hubble\\\'s law predicts superlumnial recession at large distances it is sometimes stated that Hubble\\\'s law needs special relativistic corrections when the recession velocity approaches the speed of light. However it is well accepted that general relativity, not special relativity, is necessary to describe cosmological observations. Supernovae surveys calculating cosmological parameters, galaxy-redshift surveys the cosmic microwave background anisotropy tests, all use general relativity to explain their observations. When observables are calculated using special relativity contradictions with other observations quickly arise. Moreover, we know that there is no contradiction in special relativity when faster than light motion occurs outside the observers inertial frame. General relativity was specifically derived to be able to predict motion when global inertial frames were not available. Galaxies that are receding from us superluminally are at rest locally (their peculiar velocity, Vpec=0) and motion in their local inertial frame remains well described by special relativity. There are in no sense catching up with photons (Vpec=c). Rather, the galaxies and the photons are both receding from us at recession velocities greater than the speed of light.
Comments
yourmum commented on :
I think Steve, that the question Jarsden is posing towards you, is whether or not the universe can expand at the speed of light. Something I too am very curious to find out, by also having expressed my interest in submitting my own question toward you scientists, regarding the fact that red shifting galaxies cant possibly be moving away at the speed of light if physics states this as impossible.
jarsden commented on :
I was wondering what your viwes on the topic are