Whoops! The universe isn't green, after all!

[Koggit]

This (http://www.reuters.com/news_article.jhtml?type=sciencenews&StoryID=676227) is pretty intresting. ;\

[Calhoun07]

yellow and white suns, with some red giants thrown in for good measure....why did they think it would be green to begin with??? :confused:

[Koggit]

Not sure. What I want to know is how you look at the universe from the outside. If the universe is never-ending, how is it supposed to have a definite color?

[Calhoun07]

Actually, they have long determined the universe is not never ending, that it is more than likely spherical in shape and has a definate axis and center, around which rotate all the galaxies in the known universe. What boggles the mind is the thought that there literally may be more universes out there and we are just one among many!

[Koggit]

The One. That'd be awesome! ^.^

The One had too many plot-holes, but it's still a cool thought.

[BourgeoisBuffoon]

It'd be pretty interesting to think of the 'many universes' thing. Are these universes for EVERY single different thing that could have happened? Such as a universe where it snowed in New York last night, and one where it didn't? Where simple little differences are suppose to be counted?

It's that kind of stuff that makes me think. I could be in another universe ignoring this topic. :eek:

[DR. BELCH]

Well, if you combine the light emenating from all the bodies in the solar system, then yes, the result would be white. White light is actually made up of all the colors in the spectrum (we learned it as ROY G. BIV, but I'd say there are innumerable colors between those extremes. There'd have to be, otherwise sucjh shades as brown, grey, and fuschia wouldn't exist).

It's sort of a Sliders thing, as far as alternate worlds go. In another world I might be a pretty girl. I wonder if there's some way to meet me, and if I'd even have myself? :o

[Pilmedium]

That original thought of "green" wasn't really exactly green. It was based on blue and red stars, depending on the age. It was closer to blue than red.

[Nightflower]

If there were other universes, I don't see why they'd necessarily be parallel or alternate. To me, it just seems like another unit of distance (albeit, a HUGE distance)- like there being many solar systems, and then to take it to another step, many galaxies. There's not another me in another galaxy...... I don't think..... *twilight zone music starts*

[Maxie Zeus]

Nightflower nails it. The other universes stand to our universe the same way that other planets stand to our planets, or the way that other apartments stand to my apartments. If there is no reason to think there is another "me" in the apartment next door, why should I think there's another "me" in the universe next door?


Originally posted by DR. BELCH

In another world I might be a pretty girl. I wonder if there's some way to meet me, and if I'd even have myself? :o

BTW, This is a good reason why it is problematic to think of there being other people in other universes who are the equivalent of "me." (It's called the problem of "transworld identity" in the literature.) If I (or Belch) can be a woman in another universe, why cannot I (or Belch) be a dog, or a birch tree, or a slab in the sidewalk in another universe? And if doesn't make sense to think of a dustbunny in another universe as being "me," why should it make sense that anything in that universe should be "me"? What has it got to have before it is "me"?

[Clayface]

Originally posted by Calhoun07
Actually, they have long determined the universe is not never ending, that it is more than likely spherical in shape and has a definate axis and center, around which rotate all the galaxies in the known universe.

While this is one theory, I've never read anywhere that it is definite. The fact is, we don't know if the universe is infinite or not.

[Calhoun07]

I am no scientist what I know I know from reading up in books and on web pages, but from what I understand, they HAVE determined the universe to be finite. And you may be right, there may be varying theories, but I believe it is within our grasp to know. Personally, I think it makes sense that the universe would be finite. Everything else has a center and something orbiting it, from molocules to planets and stars so why wouldn't all the galaxies in the universe be orbiting something as well?

[Clayface]

Originally posted by Calhoun07
I am no scientist what I know I know from reading up in books and on web pages, but from what I understand, they HAVE determined the universe to be finite.



Well, I'd like to see some sources on that then. My understanding is that the topology of the universe is still very much up in debate. Everything I've read says the universe could be finite. But I've seen anything that shows we've determined it to be so.




Everything else has a center and something orbiting it, from molocules to planets and stars so why wouldn't all the galaxies in the universe be orbiting something as well?


I guess I just don't follow the logic here. Yes, planets and stars certainly orbit - that's just gravity. And its certain that the galaxies in the universe can interact through such forces - though for most the effect is so small as to be negligible. But none of that means that the universe has to be finite, nor that there has to be a "center" to the universe.

[Spaceman Spiff]

Well, the universe has been expanding since the Big Bang, when it was nearly infintesimally small. There is a definite time between that event (the Big Band) and now. Therefore, the universe has a maximun size, and that is on the order of the time since the Big Bang times the speed of light (since any material from the Big Bang must travel that distance).

The debate on the shape is whether the universe is spherical, flat, or hyperbolic in time. In the three space dimensions, it is pretty close to spherical. The actual diameter of the universe would depend on the shape of it, which depends on how the mass is distrubated in space.

As for other universes, they can't affect us and we can't affect them. This is because the speed of light isn't fast enough to reach these universes; therefore, no information can be exchanged.

As for the color of the universe, it's a fallacy to think that it actually looks that way, from any perspective, as the light on the opposite side of the universe would be from stars and galaxys significatly younger (thus bluer) than the vantage point. Add to that Doppler shift, and there is no way the universe would be a uniform color.

[Clayface]

Originally posted by Spaceman Spiff
Well, the universe has been expanding since the Big Bang, when it was nearly infintesimally small. There is a definite time between that event (the Big Band) and now. Therefore, the universe has a maximun size, and that is on the order of the time since the Big Bang times the speed of light (since any material from the Big Bang must travel that distance).



Well a few things here.

#1) The Big Bang, while the most widely accepted theory right now, is not definite. There are still debates about whether or not the Big Bang was truely the "origin" of teh universe.

#2) They haven't even nailed down the rate at which the universe is expanding, or even if it is expanding. Different measurements have resulted in different rates of expansion.

#3) Yes, the matter can only travel so far in the time since the Big Bang. But what's beyond that? Where is the universe expanding into? We don't know. We don't know if there's a true barrier there on the "edge" of the universe. Thus, we don't know if the universe is truely finite.

[The Dark Knight]

There is no definite answer as to how big the Universe is. It could be infinite or finite, but by basic defenition, until someone goes all the way to the end of the Universe and sees the end, it's just a theory. Basically, if the Universe is infinite we'll never really know because it will be just a theory, and if it's finite then I don't think we'll be finding out any time soon.

Actually, I'm more interested as to when Crayola is going to release a "Universal White" crayon...

[Clayface]

Originally posted by The Dark Knight

Actually, I'm more interested as to when Crayola is going to release a "Universal White" crayon...

LOL! I can just imagine it now - the crayola box would be like the brief case in Pupl Fiction - that bright glow everytime you open it.

[Spaceman Spiff]

I guess I wasn't being exactly clear; we cannot see, or even affect anything beyond the radius of the observerable universe. In the same way, anything beyond that could not have affected us, yet. It all comes down to the speed of light. Nothing can travel faster than it, as long as we're talking about are universe. So, if you define the universe as the full set of things that can affect you, or vice versa, than there really is a finite size. And it seems to me, at least, that's the only useful definition for the universe.

As for the Big Bang, the universe is definatly expanding from a very small volume, if not a single point. Personally, I'm of the opinion that's it was a small volume and more of a Big Bounce. For all this, I'd recommend the book Elegant Universe. It covers all of this rather nicely, as well as an introduction to String Theory. (Off the top of my head, I can't remember the author, but I'll come back with it if you'd like)


Originally posted by The Dark Knight

Actually, I'm more interested as to when Crayola is going to release a "Universal White" crayon...

I can see the scene: the "Universal Turquiose" was all set for production, when Bob from accounting comes in and says, "Hey, did you hear what they're saying on the radio? It's not turquiose at all!" :D