Universe expansion is accelerating?

AI Thread Summary
The discussion addresses the concept of the universe's accelerating expansion and its relationship with the speed of light. It clarifies that while the speed of light (c) is a limit for objects traveling within space, the expansion of space itself is not constrained by this limit. The term "space expands" is debated, with a more accurate description being that objects are moving farther apart. Additionally, it notes that the recession velocity of distant objects can exceed 3c without violating the laws of physics, as this is not considered proper velocity. Understanding these concepts requires familiarity with "metric expansion."
AlbertoSalomon
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Hi i have a question, i m a engineer but i have probably a dumb question ¿if the Expansion of the Universe is accelerating, but exist a speed limit "c" this tell me that at one point the universe will expand at a constant rate?
 
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Its an often-asked question. What happens is that *space* itself expands at an accelerating rate, and is thus not bound by the speed of light. The speed of light is a maximum bound for something that travels *in* space, but space itself can expand at any rate it wants.
 
Actually "*space* itself expands" is a very contentious way of describing it. More correctly, it is simply that things get farther apart. Google "metric expansion" for more details.
 
thanks for your answers
 
You might also be interested to know that even within our Observable Universe, the recession velocity of things the farthest away from us is currently about 3c. No speeding tickets are issued because recession velocity is not proper velocity and speeding tickets only apply to proper velocity
 

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