How old is the universe? Six thousand years? Fourteen billion years? Neither? Both?
Those of you who know my theology know that I hold to Old Earth or Progressive Creationism. I take the creation days to be eras, since the sun does not appear until Day 4, and since Genesis 1 does not give an ending to Day 7.
Dr. Gerald Schroeder has a different idea, however. As an Orthodox Jew, he is committed to the authority of the Talmud, whose authors unanimously agree that "day" means "24 hour period." So he has to either discount Scripture or discount science, right? In an article harmonizing the literal reading of Genesis 1 with the observed age of the universe, he uses time dilation to show how one observer can measure an event as taking 144 hours, while another can measure the same event as taking 14 billion years.
The issue I hold with this interpretation was brought up by the Karaite Jewish scholar Shawn Lichaa. The 3500 year old dialect of Hebrew in which the Pentateuch was written is a lost language. We don't know for sure the exact meaning of every word or its usage, except in the context of other areas of the Bible in which it is used. In the Biblical contexts in which it is used, "yom" always means day, but we don't really know if it had any secondary meanings, or what those meanings were.
The following 50 minute video gives a detailed account of Schroeder's case. It gives a lot of insight into both the nature of relativity and the history of the Talmudists' interpretation of Genesis 1.