What is more?

[Jeff7]

Originally posted by: YOyoYOhowsDAjello
(and of course it was cellular peptide, but I did it anyway since I'm such a rebel)

They see you rollin', they hatin'.

 

[silverpig]

Originally posted by: Foxery

Originally posted by: silverpig
We can only see to the edge of the visible universe, and that horizon is expanding all the time...

There are no numbers for the amount of mass in the universe, nor the size of the universe. All we can say is how far we can see and what the density of matter in the space we can see is.

Er, there are plenty of estimates for amount of mass. The whole mystery surrounding "dark matter" comes from the fact that we understand how much mass there is in the universe, but can't detect all of it.

As for the size, if you take the Big Bang theory and speed of light as the basis, then matter has been flying in all directions for 14 billion years at less than c. The maximum possible size of the universe is therefore a sphere whose radius is 14 billion lightyears.

Originally posted by: silverpig
The best description of the big bang I have heard was this:

At the time of the big bang the universe was infinite, it's just that the distance between all points in space was zero.

Too vague - it was a singularity, which specifically means that the density was infinite, and its dimensions were infintesimal. That does not imply anything whatsoever about its total mass.

No there aren't. Everything is done in terms of density. When you see Omega(lambda) = 0.7, that means that vacuum energy makes up 70% of the energy density. All the energy densities add up to 1 (flat universe), and we have no idea on the extent on the universe. The mystery of dark matter comes from the fact that we know how much matter there is in a galaxy based on its rotational dynamics, and its matter distribution and how that governs the dynamics of the stars in that galaxy. Beyond that we know it must make up some percentage of the energy density of the universe, but we can't just add it all up and get a number because we don't know how big the universe is.

And as the rate of expansion increases with speed, there are quite possibly parts of the universe which are receding from us at greater than the speed of light.

Think about what you said for a second about the sphere. What's on the edge of the sphere and why are we in the center of it? One of the assumptions of the cosmological principle is that the universe is isotropic and homogeneous. Your description would put us at a special place. The only thing special about our spot in the universe is that it's the center of what we can see for obvious reasons. However, if you went 500 million light years in any direction and performed another observation, you'd see the same thing as you would on earth (within some small variation), and if you went 14 billion light years in some direction, you'd also see the same thing and you certainly wouldn't see yourself as being on the edge of some giant sphere.

Edit: one more thing.

You can't say anything about the dimensions of the universe at the big bang because it was an explosion of space as well as matter. You couldn't fly up to the universe from outside, pause time, take out a ruler and measure it expand because there wasn't anything for you to be IN to measure. No space, no time, no way for you to measure anything.

 

[SlowSpyder]

Originally posted by: destrekor

Originally posted by: DrPizza

Originally posted by: Cerpin Taxt

Originally posted by: Jeff7

There is a finite amount of matter in the Universe.

Citation, please?

I would have thought that it was general knowledge; maybe not the number, but at least the fact the the number of stars is finite. Apparently not. Wow, hopefully you guys are still in high school or something.

entertaining Carl Sagan video

Roughly 10^21 to 10^22 stars.
(1,000,000,000,000,000,000,000)

Roughly 10^79 to 10^80 atoms in the universe
10^90 photons of light.
here's another source

For what it's worth, human's tiny brains are incapable of grasping just how large 10^80 is.

Awww.... one day I was hoping to truly understand a googolplex. Yes, I want to skip the googol. (for those not following, as I know DrPizza is... a googol is 10^100, and a googolplex is 10^googol... so 10^10^100... crikey that's big eh? ) The quote that described a googolplex as being physically impossible to write in numerical citation (not enough space in the universe, according to the wiki entry), intrigued the hell out of me... then I quickly dropped it for fear I would end up driving myself into the loony bin.

Skip the googolplex and go to Graham's number.

 

[IceBergSLiM]

nerds

 

[overst33r]

The universe is finite? How so?

 

[Tim]

Originally posted by: bdude

I'm thinking nucleotides.

Arcadio, is that you?

 

[Foxery]

Originally posted by: YOyoYOhowsDAjello
Well from what I'm reading, the estimates for the volume of the universe is at least 90-160 billion light years across depending on what article you look at. The explanation for things being farther away than the age of the universe in light years is that space can expand without the limitation of the light speed barrier, so objects in the universe can and are moving away from each other at greater than light speed. I don't know enough about it to really understand the nuance of it.

Here's one of the random articles
http://www.space.com/scienceas...ery_monday_040524.html

Interesting... thanks for the link. Still trying to digest what they're describing.

It sounds like they imagine spacetime to be composed of some real fabric which stretches like a balloon being blown up, such that the definition of "distance" keeps changing. Ok. But somehow, this only allows matter to expand faster than c, but does not provide a way for light to move faster (or slower?) than c.

I don't buy it... but I'll keep thinking.

Originally posted by: silverpig
Think about what you said for a second about the sphere. What's on the edge of the sphere and why are we in the center of it? One of the assumptions of the cosmological principle is that the universe is isotropic and homogeneous. Your description would put us at a special place.

Ah, now there's the silverpig I know from Highly Technical

Sorry, I wasn't trying to imply that Earth was a privileged point - I'm aware of the theory that there are none. What I meant by the sphere was that beyond 14 billion LY, there aren't any stars. Depending on quite how spacetime is constructed, you might well be able to fly a warp spaceship out past this - you may not hit a brick wall, but there would simply be no further light sources. Nothing to see. (And nothing to detect one way or the other using telescopes from Earth.)

You can't say anything about the dimensions of the universe at the big bang because it was an explosion of space as well as matter. You couldn't fly up to the universe from outside, pause time, take out a ruler and measure it expand because there wasn't anything for you to be IN to measure. No space, no time, no way for you to measure anything.

True. I didn't phrase that well, as I was imagining "a black hole that contains all of existence."



I think we've gone slightly beyond the OP's expectations for a post in Off-Topic

 

[NikolaeVarius]

Originally posted by: mariok2006
The universe is finite? How so?

If there was a beginning, its finite.

Also, if the Universe WAS infinite, wouldn't the night sky be filled with a bright light from the infinite stars in the sky?

 

[Bill Brasky]

Originally posted by: YOyoYOhowsDAjello

Originally posted by: silverpig

Originally posted by: YOyoYOhowsDAjello

Originally posted by: Zaitsev
3.1647 billion nucleotides in human genome.Text

~ 50 trillion cells per human.

6.684 billion 'umans on Earth.

1057642.74 billion nucleotides in humans. The rest of the damn wild life makes it all hard though.

I think I'll vote nucleotides for this one.

3 billion x 50 trillion x 7 billion = 1,000,000 billion?

3 * 50000 * 7 = 1050000

Ok, so 1 trillion x 1 billion x 1 billion = 1 billion?

I rounded the numbers to make it obvious that he was off by A LOT

I don't have a problem with the 1057642.74 bit (although I didn't actually calculate it), I have a problem with the "billion" part.

He's getting ~10^15 instead of ~10^30

They're just some silly zero's. Gimmie a break! Sheesh!

 

[crownjules]

Originally posted by: Jeff7

I've heard the expansion likened to a chocolate chip cookie in the oven. The individual chips get farther apart as a function of the dough (space) expanding, and they simply rest within the medium.
Relative to empty space, you may be limited to the speed of light, but if that space itself is moving, then from some external reference, you're actually moving even faster.

Drawing dots on a balloon and blowing it up is a good example too. You can't eat it, but you can actually see the expansion of the balloon whereas the cookie dough will take 20-30 minutes.

 

[bdude]

Originally posted by: tenshodo13

Originally posted by: mariok2006
The universe is finite? How so?

If there was a beginning, its finite.

Also, if the Universe WAS infinite, wouldn't the night sky be filled with a bright light from the infinite stars in the sky?

The night sky IS filled with light from stars all around. Unfortunately ambient light and atmosphere gets in the way of viewing.

You know that saying right?

"My god, it's full of stars!"

 

[IAteYourMother]

how can it be stars winning? How can people reason that because the universe is infinite, that stars>nucleotides? There are a finite number of stars... and there are definitely more nucleotides than stars.

 

[FeuerFrei]

hang on ...
I'm still counting ...

 

[CottonRabbit]

Nucleotides by a long shot.

 

[Mo0o]

Significantly more nucleotides, it's not even close. Just googling, ESA estimate 10^24 stars in the universe.

Human body:
DNA Base pairs per cell: 6x10^9
# of cells per human: 10^13
multiplied by 2 to account for the pair

= 1.2 x 10^23 nucleotides in a human being.

World population = 6.6x10^9

= 7.9 x 10^32 nucleotides in all the human beings on earth. And this isn't even counting any other kinds of life on earth. AND not factoring in RNA which increases this amt by a decent amt as well.

 

[KaOTiK]

Originally posted by: Jeff7

Originally posted by: TallBill
The Earth is flat.

So's your girlfriend!

really lol'd to that

 

[silverpig]

Originally posted by: Foxery
Sorry, I wasn't trying to imply that Earth was a privileged point - I'm aware of the theory that there are none. What I meant by the sphere was that beyond 14 billion LY, there aren't any stars. Depending on quite how spacetime is constructed, you might well be able to fly a warp spaceship out past this - you may not hit a brick wall, but there would simply be no further light sources. Nothing to see. (And nothing to detect one way or the other using telescopes from Earth.)

Sure there are stars beyond 14b ly. What we see at 14b ly is called the last scattering surface. We're looking back in time about 13.5 billion years to about 200k yrs after the big bang. The universe was still hot and dense enough at that point that it was filled with plasma. As plasma is opaque to photons, information from that part of the universe never went very far. When the universe cooled enough and "froze out", it became transparent and those photons began their unimpeded journey to our detectors.

The stuff that's there now was plasma 13.5 billion years ago, just like we were. If you were to magically teleport to where we see the last scattering surface today and looked back at earth, you'd see the same thing... the cold echo of a once dense hot plasma. And there certainly are stars here, and there certainly are stars beyond us in the other direction

 

[silverpig]

Originally posted by: bdude

Originally posted by: tenshodo13

Originally posted by: mariok2006
The universe is finite? How so?

If there was a beginning, its finite.

Also, if the Universe WAS infinite, wouldn't the night sky be filled with a bright light from the infinite stars in the sky?

The night sky IS filled with light from stars all around. Unfortunately ambient light and atmosphere gets in the way of viewing.

You know that saying right?

"My god, it's full of stars!"

He's talking about Olber's paradox. It basically goes like this:

If the universe is infinite and thus has an infinite number of stars, and if the universe is infinitely old, then we should see a star in every direction we look, and the universe should be infinitely bright.

The main problem with this is that the universe isn't infinitely old

 

[Captante]

How many angels can dance on the head of a pin?

 

[Nik]

Originally posted by: rezinn
Yeah grains of sand are a lot smaller than nucleotides, and it's not like there are nucleotides in more places than there are sand.

Uh, what?

 

[YOyoYOhowsDAjello]

Originally posted by: Nik

Originally posted by: rezinn
Yeah grains of sand are a lot smaller than nucleotides, and it's not like there are nucleotides in more places than there are sand.

Uh, what?

(sarcasm)

 

[TuxDave]

Originally posted by: SlowSpyder

Originally posted by: destrekor

Originally posted by: DrPizza

Originally posted by: Cerpin Taxt

Originally posted by: Jeff7

There is a finite amount of matter in the Universe.

Citation, please?

I would have thought that it was general knowledge; maybe not the number, but at least the fact the the number of stars is finite. Apparently not. Wow, hopefully you guys are still in high school or something.

entertaining Carl Sagan video

Roughly 10^21 to 10^22 stars.
(1,000,000,000,000,000,000,000)

Roughly 10^79 to 10^80 atoms in the universe
10^90 photons of light.
here's another source

For what it's worth, human's tiny brains are incapable of grasping just how large 10^80 is.

Awww.... one day I was hoping to truly understand a googolplex. Yes, I want to skip the googol. (for those not following, as I know DrPizza is... a googol is 10^100, and a googolplex is 10^googol... so 10^10^100... crikey that's big eh? ) The quote that described a googolplex as being physically impossible to write in numerical citation (not enough space in the universe, according to the wiki entry), intrigued the hell out of me... then I quickly dropped it for fear I would end up driving myself into the loony bin.

Skip the googolplex and go to Graham's number.

Ow... I hate you.

 

[Nik]

Originally posted by: YOyoYOhowsDAjello

Originally posted by: Nik

Originally posted by: rezinn
Yeah grains of sand are a lot smaller than nucleotides, and it's not like there are nucleotides in more places than there are sand.

Uh, what?

(sarcasm)

Oops. Batteries need replacing.

 

[YOyoYOhowsDAjello]

Originally posted by: TuxDave

Originally posted by: SlowSpyder

Originally posted by: destrekor

Originally posted by: DrPizza

Originally posted by: Cerpin Taxt

Originally posted by: Jeff7

There is a finite amount of matter in the Universe.

Citation, please?

I would have thought that it was general knowledge; maybe not the number, but at least the fact the the number of stars is finite. Apparently not. Wow, hopefully you guys are still in high school or something.

entertaining Carl Sagan video

Roughly 10^21 to 10^22 stars.
(1,000,000,000,000,000,000,000)

Roughly 10^79 to 10^80 atoms in the universe
10^90 photons of light.
here's another source

For what it's worth, human's tiny brains are incapable of grasping just how large 10^80 is.

Awww.... one day I was hoping to truly understand a googolplex. Yes, I want to skip the googol. (for those not following, as I know DrPizza is... a googol is 10^100, and a googolplex is 10^googol... so 10^10^100... crikey that's big eh? ) The quote that described a googolplex as being physically impossible to write in numerical citation (not enough space in the universe, according to the wiki entry), intrigued the hell out of me... then I quickly dropped it for fear I would end up driving myself into the loony bin.

Skip the googolplex and go to Graham's number.

Ow... I hate you.

Interesting article from the graham's number thread
http://www.scottaaronson.com/writings/bignumbers.html

 

[Cerpin Taxt]

Originally posted by: DrPizza

Originally posted by: Cerpin Taxt

Originally posted by: Jeff7

There is a finite amount of matter in the Universe.

Citation, please?

I would have thought that it was general knowledge; maybe not the number, but at least the fact the the number of stars is finite. Apparently not. Wow, hopefully you guys are still in high school or something.

entertaining Carl Sagan video

Roughly 10^21 to 10^22 stars.
(1,000,000,000,000,000,000,000)

Roughly 10^79 to 10^80 atoms in the universe
10^90 photons of light.
here's another source

For what it's worth, human's tiny brains are incapable of grasping just how large 10^80 is.

I'm sorry, but I don't exactly take that article as a credible source. On the one hand he asserts that the number of atoms is finite, but then supports that with an argument that the mass-energy of the universe is constant.

Well, I don't know where he learned his math, but as far as I know infinity is a constant, too. Unless he's seen the edges of the universe, I don't see how he can support that assertion.

Couple that with the latest M-theory and multiverse types of cosmologies and I think it's safe to say that we can't really assert the finitude of the universe with confidence.