Nofear Posted April 22, 2013 Posted April 22, 2013 Just because galactic matter increases in speed until it passes beyond the speed of light does not mean it ceases to exist, it simply passes from our purview....Actually we can see, right now, galaxies that are and were receding from us faster than the speed of light. But that's a special scenario created by the change from deceleration in expansion to acceleration in expansion. In general what you say is true.Expanding Confusion: common misconceptions of cosmological horizons and the superluminal expansion of the universe
Questing Beast Posted April 22, 2013 Posted April 22, 2013 "Ether" hasnow been replaced by "dark matter" and "dark energy." Not a whole lot of difference.GlennThe huge difference between "ether" and "dark matter/energy" is the thinking behind them. "Ether" was an imagined concept to account for all that emptiness between the pinpricks of light that are our own planets and distant suns; there was, so far as I have heard/read, no physics driving the hypothesis of "ether". The emptiness of space must be something, so "ether" was hypothesized and its nature speculated upon endlessly; even to the point of Victorian scifi having it as breathable and capable of supporting "sailing" ships. Nobody knew that the "ether" was in fact a vacuum and inconceivably cold, although those theories existed as well and were unpopular. But now "dark matter/energy" is required to make the physics theories work. And that's all I "know" about it!...
thesometimesaint Posted April 22, 2013 Posted April 22, 2013 QB:I'm not suggesting that ether explains much of anything either. But we still have no idea as to what Dark Matter and Dark Energy are. It's like some 95% of the universe doesn't exist, except that it must exist to make what we currently know about physics work.
Questing Beast Posted April 22, 2013 Posted April 22, 2013 It's more like .000somethingorother of the universe does not exist. Dark matter/energy are 99.999somethingorother percent of the universe. "Statistically, we do not exist", some dude with the name Mark said on a YouTube video of his "atheists' conference" speech. Can't remember his name now, but he seemed like a maroon and too full of himself. I guess anyone standing there expounding on astrophysics would sound full of himself!Dark matter/energy are only mathematical concepts right now, that is so. But as far as I have heard/read, "ether" never had a mathematical component to it....
USU78 Posted April 22, 2013 Posted April 22, 2013 Unless you want to postulate that God is going to command that it reverse itself, I don't see how you can even think this could occur. There isn't some wall up against which the expanding universe is going to ram, and stop it or slow it down. It's expanding into nothing, USU. What stops it or reverses it?If the universe is into infinite expansion, it is going to become a very dark place, eventually. Nothing but red dwarfs left over billions of light years away from each other. After a few hundred billion years more, that is.People have been postulating, with various degrees of success, that the universe will either reach its limit of expansion, after which gravity pulls all that mass back together into another singularity, or it continues until everything runs out of gas. "Yes," asks the Little Prince, who never forgot a question once he asked it,"but what happens next?" Fire or ice? Does it coalesce and reignite? Or do we then have an infinity of cold?The Brahmins asked this question thousands of years ago. Do we help the universe along by quenching the fire or reigniting it?
thesometimesaint Posted April 22, 2013 Posted April 22, 2013 So far there isn't enough matter in the universe to make for a Big Crunch. So far all that Dark Matter/Energy is pulling the universe further apart. Who knows but that in some far off distant time the Gods will once again say Let there be light, and it will be.
Nofear Posted April 22, 2013 Posted April 22, 2013 Why do people keep write "Dark Matter/Energy"? Dark matter is something functionally very different from dark energy and in no way to be construed as different manifestations of a similar thing. But maybe I just don't understand the grammatical implications/rules/style/form of using/writing/employing slash-separated-words.
thesometimesaint Posted April 22, 2013 Posted April 22, 2013 Why do people keep write "Dark Matter/Energy"? Dark matter is something functionally very different from dark energy and in no way to be construed as different manifestations of a similar thing. But maybe I just don't understand the grammatical implications/rules/style/form of using/writing/employing slash-separated-words. We don't know what they are. That's why they are called "dark". It very well COULD turn out they interact with ordinary matter and energy in an ordinary way. But at this point we just don't know.The slashes are a E=MC(squared) type of thing.
Nofear Posted April 23, 2013 Posted April 23, 2013 We don't know what they are. That's why they are called "dark". It very well COULD turn out they interact with ordinary matter and energy in an ordinary way. But at this point we just don't know.We see an "influence" on space. The influence of dark energy is very different (repulsive, one can think crudely of anti-gravity) than that of dark matter (attractive in essentially the same way normal matter is attractive). It exposes a deep misunderstanding of the subject to conflate the two.
Questing Beast Posted April 23, 2013 Posted April 23, 2013 It was just a lazy way of writing about both, so I could leave out "and dark". Iirc, dark energy is 25% and dark matter is 75% of the non common or ordinary matter....
Nofear Posted April 23, 2013 Posted April 23, 2013 (edited) It was just a lazy way of writing about both, so I could leave out "and dark". Iirc, dark energy is 25% and dark matter is 75% of the non common or ordinary matter....Oops: dark matter: 25%ish, dark energy 75%ish. No matter.I find the paucity of exposure and understanding of secular cosmology by latter-day saints (and the public in general) to be rather wanting. We need to be careful about introducing misconceptions. Edited April 23, 2013 by Nofear
Questing Beast Posted April 23, 2013 Posted April 23, 2013 Oh, yeah, I did the dyxlesic thing there, even with rereading it carefully, still didn't catch it. Oh, well....
thesometimesaint Posted April 23, 2013 Posted April 23, 2013 We see an "influence" on space. The influence of dark energy is very different (repulsive, one can think crudely of anti-gravity) than that of dark matter (attractive in essentially the same way normal matter is attractive). It exposes a deep misunderstanding of the subject to conflate the two.I never said they were the same in force or influence. They are the same(Dark) in that we know virtually nothing about them.
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