Infinity and our Existence

[Reach]

The Univere IS infinite

Incorrect. At least with respect to our universe. All WMAP observations confirm with great detail the big bang, and that the universe is still expanding. Since the universe is still observably expanding, by definition it is not infinite as it is bound by the finite rate of expansion.

[Falco_L]

Originally Posted by Adamaja456

I strongly believe that space in infinite. So how can you make the probability using the volume of something that is infinitely big? I dont see how you can say one goes to infinity. I'm not trying to be rude, I'm just trying to wrap my head around this topic =]

You can use the probability per unit volume of something with near infinite volume by multiplying my something which is near zero. The two will "cancel out" and produce a finite number. You can think of this as a limit:

For instance, 1 x 1 = 1.
Also, 10 x .1 = 1.
Also, 100 x .01 = 1.

You can imagine what would happen if you kept making the first number bigger and the second one smaller, proportionally. Eventually, one would approach infinity and the other would approach zero, but the product would still be 1. This is a relatively simple concept of calculus (the concept of a limit).

I hope this answers your question; I'm not entirely sure I understood what you were asking.

[Hollus]

Originally Posted by Reach

Incorrect. At least with respect to our universe. All WMAP observations confirm with great detail the big bang, and that the universe is still expanding. Since the universe is still observably expanding, by definition it is not infinite as it is bound by the finite rate of expansion.

Reach is correct. However, even the distance between our planet and the nearest star is mind boggling. When you think about the billions (trillions?) of stars in our universe, all the planets and galaxies, it goes beyond human comprehension. Its easily to say " 100 light years", but when you of it in terms of " 100 km/h for 99999 years" or whatever, it gets a little harder to think about. The universe IS huge, even if it isn't truly infinite, it easily exceeds the limits of our imagination. There's a lot of space out there.

(Unfortunately, Falco_L is incorrect. No matter how large the first number gets, it won't even come a tiny bit close to infinity, just like the second number never gets to zero either.)

[ledwix]

If you are a supporter of the Big Bang Theory, the universe cannot be infinite:

-A "definite" amount of mass equal to the mass of today's universe should have existed at time = 0 seconds, if the Conservation of Mass works.
-An infinite amount of universe space means that there is an infinite amount of mass in the universe.
-An infinite mass at one point cannot be accelerated outward, since gravitational force is also infinite.
-String theory would be the only way to refute through science, but I'm not sure how far we can go when examining things on the order of 10^-35 meters.

Also, on the topic of extraterrestrials:
-If there is any chance above zero that life on other planets exists, and the universe is infinite, then life on other planets exists, because the chances of it existing are infinitely close to 100%. If you are an evolutionist, then the chances of life emerging from non-life is above zero, since this world is an obvious example of life. Therefore, an infinite universe would mean an infinite number of alien civilizations under those circumstances.

[jewpinthethird]

Originally Posted by Hollus

Reach is correct. However, even the distance between our planet and the nearest star is mind boggling. When you think about the billions (trillions?) of stars in our universe, all the planets and galaxies, it goes beyond human comprehension. Its easily to say " 100 light years", but when you of it in terms of " 100 km/h for 99999 years" or whatever, it gets a little harder to think about. The universe IS huge, even if it isn't truly infinite, it easily exceeds the limits of our imagination. There's a lot of space out there.

Yeah, but it's not infinite. At least, we don't have any solid evidence to either make that claim, nor deny it.

Again, to make another nonsensical claim that can't be proved, why stop at a Universe? Why can't there exist a Multiverse? I mean, quantum physics has shown that matter keeps getting smaller and smaller and astronomy has shown that even galaxies cluster together.

[Hollus]

Originally Posted by jewpinthethird

Yeah, but it's not infinite. At least, we don't have any solid evidence to either make that claim, nor deny it.

Again, to make another nonsensical claim that can't be proved, why stop at a Universe? Why can't there exist a Multiverse? I mean, quantum physics has shown that matter keeps getting smaller and smaller and astronomy has shown that even galaxies cluster together.

The universe isn't infinite, but the distances involved are just so huge. Maybe there is a multiverse, or an infinite amount of finite "universes". That makes sense, in a poetic sort of way. But, of course, not provable. Now, anyways.

[Smok3y]

If anything is infinite, like the universe, would there even be a way to prove it? Seems unlikely... I like the idea of it being finite though, it'd be interesting the learn what the "borders" are like.

[Falco_L]

Originally Posted by Reach

Incorrect. At least with respect to our universe. All WMAP observations confirm with great detail the big bang, and that the universe is still expanding. Since the universe is still observably expanding, by definition it is not infinite as it is bound by the finite rate of expansion.

I would like to point out, simply as a very interesting thought, that even though the universe seems huge, the only observations we have of it are of the visible universe, limited in size by the speed of light. The actual size of the entire universe may be billions of times larger than what we are able to observe. We can only see objects which are close enough to us such that light coming from them has had time to reach us; this distance is approximately 15 billion light years, the age of the universe according to current evidence. This is also why the visible universe is expanding at exactly the speed of light.

This leads to still other very interesting things which I would love to go on about here, but it would take too much space and it's not relevant to the topic.

[Adamaja456]

Originally Posted by Reach

Incorrect. At least with respect to our universe. All WMAP observations confirm with great detail the big bang, and that the universe is still expanding. Since the universe is still observably expanding, by definition it is not infinite as it is bound by the finite rate of expansion.

Yes, the universe is still expanding but have we charted the end of the universe? I'm not sure how far into Space NASA has seen with powerful telescopes and satellites but until theres some sort of proof to the "end of space" its easier to think of space as infinite

Also, since the universe IS expanding, i can see where its easy to think there must be parameters but think about this.


Think of the universe as a balloon. It starts out as a little dot and constantly grows larger and larger. But think that the balloon can expand to infinity. Although it may look like theres parameters to the universe, it still seems to expand and get bigger. Wouldnt this make the Universe infinite?

EDIT: "Eventually, one would approach infinity and the other would approach zero, but the product would still be 1"

i thought any number times 0 would produce 0. So wouldnt Infinity x 0 = 0 not 1?
But your logic does seem to make sense.

[Reach]

I would like to point out, simply as a very interesting thought, that even though the universe seems huge, the only observations we have of it are of the visible universe, limited in size by the speed of light

Well, yes. We're now actually pretty sure the visible universe is significantly larger than simply the age multiplied by the speed of light though, because of inflation. But yes there could be any amount of 'space' outside of what we can see right now.

Yes, the universe is still expanding but have we charted the end of the universe? I'm not sure how far into Space NASA has seen with powerful telescopes and satellites but until theres some sort of proof to the "end of space" its easier to think of space as infinite

Also, since the universe IS expanding, i can see where its easy to think there must be parameters but think about this.

You don't need to chart the end of the universe. If something is expanding quantifiably, by definition it is not infinite. It's as simple as that. Why? Unless the rate of expansion is infinity, the universe will always have a measurable, finite size if it is expanding quantifiably.

But uh, either way I think WMAP can see the whole universe using old light. It is generally understood that the universe is finite but has no physical boundary. That is, you are never going to get to somewhere and hit a wall or see the end of space. It doesn't work that way...think of it like earth where you'll just keep going around and around. The difference here being up into the sky is another dimension we're incapable of perceiving, and thus cannot leave the universe.

To imagine this you have to put yourself in the higher dimension. We are like stick figures drawn onto a paper ball. We don't have the spatial capacity to leave the paper ball, yet although the ball appears two dimensional to us, it is actually three dimensional.

Think of the universe as a balloon. It starts out as a little dot and constantly grows larger and larger. But think that the balloon can expand to infinity. Although it may look like theres parameters to the universe, it still seems to expand and get bigger. Wouldnt this make the Universe infinite?

The problem here is you can't expand to infinity, so no this wouldn't make the balloon infinite. If you can measure the space inside the balloon at any given time, it is not infinite. In order for the balloon to be infinite it would have to reach a state of infinitely fast expansion.

And uh, that would destroy the universe so it's out of the question It is a rather well known problem for us now, that in around 50 billion years or so the universe is going to be expanding far too fast for energy to maintain the state we know it as. Thankfully we won't be around for the universal annihilation though ;o

[Adamaja456]

Originally Posted by Reach

Well, yes. We're now actually pretty sure the visible universe is significantly larger than simply the age multiplied by the speed of light though, because of inflation. But yes there could be any amount of 'space' outside of what we can see right now.



You don't need to chart the end of the universe. If something is expanding quantifiably, by definition it is not infinite. It's as simple as that. Why? Unless the rate of expansion is infinity, the universe will always have a measurable, finite size if it is expanding quantifiably.

But uh, either way I think WMAP can see the whole universe using old light. It is generally understood that the universe is finite but has no physical boundary. That is, you are never going to get to somewhere and hit a wall or see the end of space. It doesn't work that way...think of it like earth where you'll just keep going around and around. The difference here being up into the sky is another dimension we're incapable of perceiving, and thus cannot leave the universe.

To imagine this you have to put yourself in the higher dimension. We are like stick figures drawn onto a paper ball. We don't have the spatial capacity to leave the paper ball, yet although the ball appears two dimensional to us, it is actually three dimensional.





The problem here is you can't expand to infinity, so no this wouldn't make the balloon infinite. If you can measure the space inside the balloon at any given time, it is not infinite. In order for the balloon to be infinite it would have to reach a state of infinitely fast expansion.

And uh, that would destroy the universe so it's out of the question It is a rather well known problem for us now, that in around 50 billion years or so the universe is going to be expanding far too fast for energy to maintain the state we know it as. Thankfully we won't be around for the universal annihilation though ;o

yea you seem to make a clear point. Thanks for the information. That has helped me understand a little bit better about our universe=]

Thank You

~Adam

[slipstrike0159]

Originally Posted by Reach

Incorrect. At least with respect to our universe. All WMAP observations confirm with great detail the big bang, and that the universe is still expanding. Since the universe is still observably expanding, by definition it is not infinite as it is bound by the finite rate of expansion.

Actually, to make this the most correct statement you would have to change it to say "the universe as we currently define it". Everyone thinks of the universe as a giant sphere expanding into nothingness, however, it would also be plausible to think that in nothingness there is also another sphere that is expanding which would also be a "universe" such as jewpins multiverse. If we were to gain knowledge that would lead us to believe this, then our concept of the universe would shift to being what contains the two rapidly expanding spheres. In this such case, it could be infact infinite if knowledge continues to grow without a stopping point.

Also, infinity in of itself is a concept and nothing more. You cannot prove or disprove infinity because you are bound to finite lives in the realm of time and existence. If you could infact break these bonds and live outside of time which allows you to see it as a whole, then you could see a specific even never ending. Aside from this, it is just a concept used to describe an event (such in math) where and increase or decrease of data will not end according to its parameters.

[coolade123]

Scientists say, I believe, that if you keep going in the Universe, you will eventually hit another planet indenticle to ours, with people living on it and technology like ours. I am very confused with this subject but it is a very interesting one.

Also I'm not sure if this deserves to be in another thread, but now we get to the idea of black holes. If you get sucked through a black hole where would you go? Science proves that black holes exist, but where do they take you? I would expect them to take you to a completely other Universe so maybe there are other Universes.

[devonin]

Well, there's a theory out there that there exists something called white holes, that simply eject matter, that could possibly be the "other side" of black holes, but since the gravity in a black hole is so intense that even light can't escape it (Thus why it's a -black- hole) there doesn't exist even the possibility that something as fragile as a human could somehow survive transit through one.

[Kilroy_x]

There's actually conjecture these days that Black Holes might be driven by a force other than gravity. I don't know how white holes are purported to work, but black holes actually emit information in the form of heat radiated from them IIRC which corresponds to what went into the black hole.

[devonin]

Which implies perhaps that matter entering black holes is somehow broken down into some form of kinetic energy?

[Relambrien]

EDIT: I use the word "theory" here not in a scientific sense, meaning I don't mean "theory" to mean "an explanation for a phenomenon supported by several experiments." I mean it to mean "a proposed explanation of a phenomenon." I know it's not the right way to use the word, but I realized what I did after posting, so just bear with me.

Wikipedia has a great set of articles on black wholes and white holes; I won't bother listing everything here because most of it is beyond my comprehension, but I suggest looking at it if you're interested in the topic.

Also, Reach spoke about "the end of the universe," as the universe is expanding at an increasing rate. If this trend continues, the result will be either the "Big Rip" or "Big Freeze," (which can also be found on Wikipedia). The "Big Rip" theory simply says that once the universe expands at a sufficiently fast rate, the space between atoms will extend to the point where objects are broken down, largest to smallest. Galaxies will break apart, followed by solar systems, then planets, then the things on the planets (e.g. us), and finally the atoms themselves.

The "Big Freeze" says that as the space between atoms increases, heat necessarily decreases since heat is caused by the friction between atoms, which would decrease. Once the atoms are sufficiently spaced apart, friction will become low enough to reduce everything in the universe to, I believe, absolute zero.

Those are just two theories however; Wikipedia has an entire article about the end of the universe you could look at for more. The "Big Crunch" theory is also interesting to look at.

[Reach]

Also I'm not sure if this deserves to be in another thread, but now we get to the idea of black holes. If you get sucked through a black hole where would you go? Science proves that black holes exist, but where do they take you? I would expect them to take you to a completely other Universe so maybe there are other Universes.

In reality you would never be able to get anywhere near a black hole. The radiation it gives off would kill you long before much of anything happened. Even if you did somehow get past that part, which you wouldn't, the gravitational force would kill you before even reaching the part of the hole that is completely black ;o

So no worries about getting through to the other side, although there probably isn't one. If you were to keep going deeper into the hole you would reach a singularity, which is a very mysterous place indeed. There is little agreement as to what is actually going on in the singularity and what it is, other than being an incredibly small point at the center, and the source of an astronomically large gravitational force in a tiny space. General relativity and classical mechanics fail completely at describing the singularity.


Relambrien brings up some of the other end of the universe hypothesis, however, the big rip and freeze are really different descriptions of the same scenario. The data we have right now only supports this hypothesis, and the big crunch is impossible given the current composition of the universe. The universe is nearly 3/4 dark energy, and there is no sufficient gravitational force to stop the expansion at this point.

[Master_of_the_Faster]

Originally Posted by Reach

In reality you would never be able to get anywhere near a black hole. The radiation it gives off would kill you long before much of anything happened. Even if you did somehow get past that part, which you wouldn't, the gravitational force would kill you before even reaching the part of the hole that is completely black ;o

Ok, so perhaps we wouldn't just send human beings randomly if we knew that blackholes would kill us with radiation or a gravitational force, but would it be reasonable if we send some sort of item that could get past these barriers and go to see what is on the "other side"?

[devonin]

Something that small that generates enough gravity to pull light directly into it is not (Correct me if I'm wrong, science people) that anything manmade could possibly survive.