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Is the speed of light actually slowing?
I heard this comment the other day from a speakers I don't consider highly credible. He said, "its become widely accepted that the speed of light isn't a constant but its changing (slowing) very slightly." He went on to present some anecdotal evidence. I certainly think it would be fascinating if true but I'd never heard this before AND as I said, I have my doubts about the credentials of the speaker. Can anyone verify for me if this is an accepted fact or a cutting edge maybe or utter non-sense?
2 Answers
- mayo_carlLv 78 years agoFavourite answer
the speed of light (c) was first measured in 1676, and has been measured many times since then. each measurement has arrived at a speed that was slightly less than the one before it, with only a few exceptions.
if these were errors due to math or measuring techniques, one would expect roughly half of the results to be above--and half below--the current measured value of c. instead, the measurements show an overall decline in c over time, following a predictable curve.
this has led to speculation that c is not a constant, but is actually slowing along with the stretching of space-time.
the short answer is that we cannot yet prove that c is slowing, but it cannot be ruled out either.
if the entire universe is subject to entropy, then we can't automatically ignore the possibility that physical constants may not be constant after all.
