How Universe is expanding faster than speed of light?

AI Thread Summary
The discussion centers on the concept of the universe expanding faster than the speed of light, which is not a contradiction due to the nature of cosmic expansion. While nothing can travel faster than light within space, the expansion of space itself can cause distant galaxies to recede at superluminal speeds. This phenomenon is explained through the framework of general relativity and the metric expansion of space. Length contraction and the nature of coordinates in cosmology are also relevant to understanding this concept. Ultimately, while parts of the universe may appear to move away faster than light, they do not actually exceed the speed of light in a physical sense.
SecretOfnumber
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Hi Guys ,

Just read this at The NASA site:

http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/070904a.html

""Q ...My question is if the universe is accelerating, eventually should it not reach a speed faster than the speed of light? Has anyone investigated the question as to what will happen if the expansion of the universe breaks the light speed barrier?

The Answer

A :Thanks for your question. It is true that nothing can go faster than the speed of light. And it is also true that our universe is expanding faster than the speed of light today. This sounds like a contradiction, but..."""

Could some one explain this to me please ?perhaps a little about length contraction... !sorry I just don't get it!

Cheers,:confused:
 
Space news on Phys.org
Its a metric thing. Coordinates on the graph paper are not constrained.
 
Thanks ,I guess I know what you mean, but does this is "actually "is happening in a physical world?
 

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