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Honest question: How does this relate to the apparent ages of stars, then? If light from 10 billion light years away has the added component of this "faster than light expansion", doesn't that skew the age to younger than 10 billion years?

If light from 10 billion light years away has the added component of this "faster than light expansion", doesn't that skew the age to younger than 10 billion years?

I don't think he said that the universe was expanding faster than light now -- just that it might do so.

But, still -- if the "distance" we observe is determined by an assumption that is not true (i.e. constant speed of light, no expanding universe) ... well, seems to me that any correction one would make on the basis of the new evidence would have the effect of making the universe younger than Sagan's "billions and billions of years."

Now, I wonder if anyone will attempt to determine what the rate of increase in the expansion is? Or, having done that, what the result will be when the age of the universe is reckoned on the basis of this data?

Honest question: How does this relate to the apparent ages of stars, then? If light from 10 billion light years away has the added component of this "faster than light expansion", doesn't that skew the age to younger than 10 billion years?

This is probably a bad explanation but here goes:

Time (due to due to relativistic time dilation) slows down as objects speed up. Thus even though the universe is expanding, light did indeed leave the object in question 10 billion years ago.