So how big is the universe anyway?

[fuindordm]

So does the new, post 2003 opinion still leave open the idea of an finite but unbound universe that is still expanding? I've always found the idea interesting, plus getting around the idea of an infinite and expanding universe with a finite amount of matter in it. Or perhaps I just don't like to work with infinities. Or that I'm a biologist and cosmology stuff is just a cool thing to read about, but hardly an area of focus for me.

No, not really. We can measure the amount of matter in the universe pretty accurately, and that's never been an option. A finite universe will always eventually collapse under the current models.

The analogy often made is that of a rocket trying to escape the Earth's gravity. If it has too little speed, then it will fall back to the ground. The universe has a speed of expansion that we can measure today, and it's much greater than what is needed to 'escape' its own gravity.

Ben

 

[Tinker Gnome]

I had a friend who was so fat, we had to kick him out of the universe!

 

[Cheiromancer]

You know how google has this service whereby you can look down at any point on earth, from any height, as if you are flying over it? (Lots of places the resolution isn't very good, but often you can see cars and stuff)

I wonder if there is anything like that for star systems? So you can practice flying from Alpha Centauri to Epsilon Eridani and back. Anybody know?

 

[Algolei]

I wonder if there is anything like that for star systems? So you can practice flying from Alpha Centauri to Epsilon Eridani and back. Anybody know?

Well, I haven't tried it, but I've heard about something called Celestia.

Would you like a link, or can you Google it yourself?

 

[The_Universe]

I think he is about 5'8".

5'10", actually.

 

[The_Universe]

I think my wife can confirm that her expansion happened after the big bang.

One of the Discworld books had a wonderful bit about the myth that the world turtle, Great A'Tuin, was heading towards a cosmic breeding ground. In the Discworld this was also known as the Big Bang theory.

Ben

Giggity giggity. Aaaaalright.

 

[The_Universe]

Why do you know this and does Queen D know you do? Does The Universe?

The Universe:

Large enough to get the job done, and then some.

Heh.

 

[Cheiromancer]

Well, I haven't tried it, but I've heard about something called Celestia.

Would you like a link, or can you Google it yourself?

Very cool. Now if only I would stop getting lost in the solar system....

 

[Harmon]

So how big is the visible universe? About this big. You have to zoom all the way in to find the Sun. Yowsers.

My nephew asked me this question a few years back and my answer was something like- "you know how big huge is?"
"Ya," he replied.
"Is there anything bigger?"
"Umm- the universe?"
"You got it."

Not very scientific, but when your trying to answer questions to a kid, those kinds of answers work very well.

 

[Algolei]

Very cool. Now if only I would stop getting lost in the solar system....

It is cool! I was up fooling around with it myself last night when I should have been sleeping but bah who needs sleep I don't need sleep I'm a third level fighter.

Boy, was I absurdly frightened when I thought, "I can't find my way back to Sol!"

Is there a way to just scoot around free-style? All I can find is the Goto thingy, which zooms me toward stuff. But I wanna scoot aboot like Gary Gygax in an X-Wing fighter. (I maintain my alienable right to mix metaphores willy-nelsonny.)