Started by Baruch, April 01, 2018, 07:03:23 PM
Quote from: Unbeliever on July 01, 2018, 05:31:56 PMYou mean the Ka'aba might be this "Petra"!? Interesting! So "the Rock" is literally a rock. I like that idea.
Quote from: Unbeliever on July 01, 2018, 05:44:18 PMContrary to popular belief, the universe isn't really getting any bigger. It's always been infinitely large. But its density and temperature are decreasing, which does look to us like an expansion. Even our finite observable universe isn't growing, since the horizon is fixed. Eventually there will be only a single particle, if that, in all that space as the density and temperature decrease to very near zero (10^-29 degrees K). But the universe won't be any bigger.:-)
Quote from: Cavebear on July 02, 2018, 12:52:04 AMI get annoyed when some scientists refer to "seeing to the start of the universe", when what they mean is "as far as we can see" via light.
Quote from: SGOS on July 02, 2018, 05:43:46 AMYou get used to it. I attended a lecture put on by some Cal Tech guys that used the "looking into the past" description, rather than the "far away" description. It was disconcerting to me, but by the end, it made perfect sense. These guys were studying the formation of galaxies, where you have to look into the past to see what galaxies look like in their early stages. Then looking at things far away becomes looking into the past. In fact, everything far away is the past, and what you see is not even there today, or at least in a different form. The fact that it's far away is really of little importance beyond party conversation: "I once saw a star that was 13 billion light years away." Big whoop. "What does it look like?" "I don't know. I can only see what it looked like 13 billion years ago. I don't even know if it's still there."Astronomy is about looking at the past. No matter how far away something is, it's all in the past. You can't see the present when you look far away. You can only see the past. And looking at a far away galaxy tells you nothing about the present.It's true that both perspectives amount to the same thing, but which perspective is better is only a matter of someone's perspective.
Quote from: Cavebear on July 02, 2018, 06:12:41 AMI used to get people annoyed decades ago saying we saw 13 billion years into the past. A slight science knowledge as filtered in though.Bit by bit, knowledge accumulates in spite of so many people fighting against it. And time is relative at even local distances. If I look at a person, technically, I am seeing the nose fractionally sooner than the rest of the face. Fortunately, it doesn't matter much. But it is real.