I find it very difficult to understand how some consider the Universe to be possibly finate. If someone could explain to me their understanding of a finite Universe, I would be grateful.

The reason I have a problem with a finite Universe is this.

You see I have this stuff.  Where do I keep this stuff?  I keep it in a jar.  Where is the jar?  Its in a cupboard.  Where is the cupboard? Is it a big cupboard?  Yes fairly big, its in my kitchen.  The kitchen is in my house.  Fantastic, and where is the house?  Its located in a suburb close to a big city.  Oh, and which County is it in?  Its in so and so County. That's in so and so Country right?      Yes thats right.  This is planet Earth we are talking about?  Yes, its a fantastic place. If you have never seen it you would not believe it was possible. Where is the Earth exactly?  Well now thats a tricky one, because you see everything is moving about. Nothing seems to stay still for a second.  But I will try to explain it roughly.  It is in a solar system that it shares with eight other planets, three dwarf planets and one hundred and seventy moons. This solar system is part of a galaxy called the milky way.  And where is this galaxy? Good question. Well its er, part of the Universe.  And where is this Universe? I mean, what is the Universe in?  It has to be in something, right?  You can't just stop at that.  Nope, your right.  It must be in something,  unless, unless it is Infinite.    Well anyway, that is where this stuff is.

If anyone has some stuff in a finite Universe, could they please explain to me where they keep it.  All of it, including the finite Universe!

dalli : Yes it is sort of overwhelming, not only where it is but also when it is, right? Not only is it in the universe but in something called the multiverse, and after that, the ultra-cosmos, then after that, you name it, so on, and so forth. But still, it could have limits, maybe. I sort of think there is a dimension we should call why it is. We could call it Knowledge. Just joking, sorry I can't give you a good finite answer.

I see your quandary. When philosophers theorize, there are no limits except their imaginations. When scientists theorize, they base their discussions on evidence.

So, a scientific theory must work from observable, measureable, testable evidence. There is, so far as I know, only philosophical reasoning -- not scientific evidence -- for thinking the universe to be infinite.

As an example, consider what happens when we think about a day on Earth. We see the Sun rise in the morning, follow a path through the sky throughout the day, and set at Night. The next morning the cycle repeats. The only variations are the changing of the seasons and march of the constellations throughout a year. The learned philosopher would say that everything revolves around the Earth, and that Earth is immovable at the center of the cosmos. However, scientific evidence (for example, the rotation of a Foucault pendulum) shows us that this is not the case -- that our philosophy is flawed.

While the lack of evidence for an infinite universe does not, by itself, mean it is not infinite, that's different from stating (scientifically) that it is infinite. To overcome scientific objections to a Big-Bang-based finite universe, a scientist who proposes an infinite universe must find a way to explain how matter is continually being created to support what is observed to be an expanding universe (that is, where is the "new" matter coming from?).

Obsession is the only reason we have a limited universe and a flawed model. Obsession with origins! When was the first this or that? Where did it come from? Who cares... it's here now and we should all be happy we are alive to enjoy this universe.

If the universe was born from nothing then so were we. A cosmic egg that didn't explode, that didn't contain anything, that only exists in the imagination, that cannot be located is part of the BB theory. There is absolutely no evidence of the egg itself.

How far we can observe gives us our "scientific" size of the universe. My belief is that there is no scientific reason to believe that anyone, anywhere else in the universe isn't able to observe the same thing we do. This makes the universe infinite.

Infinity makes even scientists seem insignificant and that is why they do not accept it. It has NOTHING to do with evidence or how far we can observe. Science is the offspring of philosophy and regardless of what we think we know, proof is not always evident and sometimes can only be found in the mind. It is not always right. The cosmic egg is one of these ideas.

BQ 

 It's funny, I just wrote up a long thread proving that our universe is finite.

In a nutshell my argument is that if space time is growing and has continued to grow since the big bang, then it is not infinite. Something that is infinite is already everywhere and would be unable to grow. So if our universe, is just a word we use to describe all of the matter and space time in our known existance, then that description is of a growing universe that is not everywhere, it is growing larger yes, but if it were infinite how would it grow?

 If you agree that the universe is not infinite the next questions is what is it growing in? If you think of our universe and space time as a bubble that is inflating, where is that bubble? It is growing inside of something right?
 

Kodack :  You asked " but if it were infinite how would it grow?" Magnitude is relative. Infinity is a measure of magnitude. 

 That is a symantec argument though. Infinite would be without end, everywhere at once. If something is already everywhere, it can't expand because it's already expanded.

Also we know with certainty that our universe was once compressed into a singularity at the point of the big bang so it was not infinite then, and it has not become infinite since. It's just really really big.  

brooksquest:

Obsession is the only reason we have a limited universe and a flawed model. Obsession with origins! When was the first this or that? Where did it come from? Who cares... it's here now and we should all be happy we are alive to enjoy this universe.

Where?, when?, and how? are the questions which drive science.  Why? is the question which drives philosophy.  There is nothing wrong with either endevor.  Curiosity is not obsession.

If the universe was born from nothing then so were we. A cosmic egg that didn't explode, that didn't contain anything, that only exists in the imagination, that cannot be located is part of the BB theory. There is absolutely no evidence of the egg itself.

But there is ample evidence of what occured after the 'egg' hatched.  If I see a chick, and I see a shattered shell, and if I have a rudimentary understanding of avian biology, I can infer a hatching.

How far we can observe gives us our "scientific" size of the universe. My belief is that there is no scientific reason to believe that anyone, anywhere else in the universe isn't able to observe the same thing we do. This makes the universe infinite.

There is also no scientific reason to believe they would observe the same thing, since we can not observe from their perspective.  All we can do is utilize the observations we can make.

Infinity makes even scientists seem insignificant and that is why they do not accept it. It has NOTHING to do with evidence or how far we can observe. Science is the offspring of philosophy and regardless of what we think we know, proof is not always evident and sometimes can only be found in the mind. It is not always right. The cosmic egg is one of these ideas.

Proof is based in evidence, never found in the mind.  What you are describing is belief and faith, also offsprings of philosophy.  Science does not tell us what to believe, it only attempts to define what we can see, touch, and measure.  Our own philosophies tell us how to interpret those definitions.  In my opinion, we waste a lot of energy when we try to hold our science in one hand and our beliefs in another instead of putting them together in one pocket and getting on down the road.

Kodack : I like your approach, but infinity doesn't have an absolute value. You know, math is full of unknowns, no pun intended. I like to think of magnitude as a dimension ( or a pseudo-dimension) subject to relativity.

 To put it another way, if something is infinite how could one tell if it were expanding or contracting. If it is truly infinite it can neither grow nor shrink because in order to do that it would need a boundary to move and a boundary would not be infinite.

A similar argument would be if something were infinitely black, it would be impossible for it to get any blacker. Or if something were infinitely bright it could not possibly get brighter. Any change in brightness would indicate it is not infinite. If it get's brighter it means it wasn't as bright as it could have been and if it gets dimmer it means it's not as bright as it could be, both of which would mean it has boundaries.

The idea of an expanding universe becomes really interesting to me with respect to questions that haven't been asked yet. We know it's expanding but aren't we assuming it will always expand, or that it has always expanded before? And we are we sure the expansion is uniform or at a constant speed?

It seems to me that if we could study the rate of expansion, and we also know how old the universe is going back to the big bang, then we should be able to work out how big the universe is. IE if you took expansion out of the equation and you know how old the universe is, and you know the speed of light, and you know nothing moves faster than the speed of light, then you can work out how big the universe could possibly be. Expansion muddles that up because new space is being created, but if we could account for it by studying it, we may one day be able to say exactly how large the universe is, how big it will be when our sun dies out, how big it will be when our galaxy gets in a car wreck with Andromeda, and maybe even if there will be a big squeeze or if it will just keep flying apart until the suns die out and the universe goes dark and dead.  

PS Zachsdad. It's true that science needs observable and repeatable data in order to make progress. But sometimes what we observe doesn't make any sense and it take a leap of imagination to make any progress. Einstein was a big proponent of using thought experiments as scientific tools. Given that no human being has ever been outside of the earth's magnetosphere much less to another world, and our limited and dim view of the galaxy around us, you might say everything we know about the universe comes from conceptualized ideas and ideals that are backed up by minute pieces of observable data.  

Kodack:

 PS Zachsdad. It's true that science needs observable and repeatable data in order to make progress. But sometimes what we observe doesn't make any sense and it take a leap of imagination to make any progress. Einstein was a big proponent of using thought experiments as scientific tools. Given that no human being has ever been outside of the earth's magnetosphere much less to another world, and our limited and dim view of the galaxy around us, you might say everything we know about the universe comes from conceptualized ideas and ideals that are backed up by minute pieces of observable data.  

I think I have to dissagree with this.  Of course there is a need for imagination and creativity in science, but scientists don't generate ideas out of whole cloth and then run out and look for data to prove them, they use their imaginations and creativity to generate possible explanations for the data and observations that have been made.  Then they run out and look for data to confirm those explainations.

zachsdad:

Scientists don't generate ideas out of whole cloth and then run out and look for data to prove them, they use their imaginations and creativity to generate possible explanations for the data and observations that have been made

 So do non scientists. :)

 I wasn't suggesting we have our fantasies and then build evidence to support them, that's what crazy people do. :)

 Thought experiments are our best way of conceptualizing that which we cannot see. I think of it as running a simulation in your head.

 

You Wrote:

"There is also no scientific reason to believe they would observe the same thing, since we can not observe from their perspective.  All we can do is utilize the observations we can make."

WE can see beyond their perspective. WE would have to be pretty arrogant to think that "they" cannot see beyond ours. Is there a way to determine anyone, anywhere who would not be able to observe as we do? I do not think so, but, there is no scientific reason to limit the size of the universe. Our ability to observe so little is part of the problem because our puny brains can't fathom a universe beyond our view plus expansion. Who are we to say that the horizons stop with us?

Because our view of the COSMOS is so limited, it is truly silly to even think of COSMOLOGY as a science. 99.9999999999999999999999999999999999999999999999999999999999999999999999... percent of the subject is completely unobservable and therefore "non-scientific". Comparisons only take us so far unless we assume that everywhere else is like here, universally speaking. If we assume this then everyone else sees what we see "to infinity and beyond" (to quote a famous action figure). 

Cheers,

BQ 

 Well brooksquest as far as our minds being too puny to understand how large the universe is, I would like to challenge you.

We have mostly charged our own solar system, we know how far apart everything is, a good guess of their masses, sizes, composition. Even a school kid can probably name the planets in order. But at the same time we have trouble conceptualizing things like how many grains of sand there are beneath the ocean. Or trying to imagine what floating above our planet would be like. Or even our local geography.

 I'm sure you know your own street in a lot of detail, and your neighborhood pretty well, when you start moving out into your city you know where the major things are but you start to loose your grasp of the "whole", as you move out into a county area mindset you no longer think of individual streets and houses, you are now thinking in terms of cities, highways, lakes, etc.

Our minds are not capable of comprehending so many bits of information at once so it begins using placeholders like your image of your city instead of the actual mental map of your entire city as it fits into your entire state and country and world.

 Yet you can read a map, and you don't get lost that often because while you don't know everything, you know enough.

Yes it would be impossible to really "know" how large the universe is or to conceptualize it, the same way it's impossible to conceptualize what it would be like to live on the surface of Jupiter, or plot a navigational course on the fly from the moon to the earth.

 Our lack of total god like awareness of everything doesn't mean we are too puny minded to study it, learn from it, chart it, classify it, and ultimately trivialize the information we glean from it.

And from a science stand point saying "the universe is too big for us to understand" is almost a cop out answer that doesn't answer anything. That kind of statement is designed to keep people from asking questions.

We take for granted that most of our knowledge of scientific discovery was learned in hindsight by following the works of others. It's much harder, and it has always been difficult, to discover things and make those leaps of logic that change the way we look at the world. Just because something is hard doesn't mean it's impossible.

It was hard to put a man on the moon and bring them safely back home. However, the first people who sailed from Europe to the new world took on a journey that was both more expensive (taking inflation into account), more dangerous, and more world changing.

You should never dismiss something as impossible, that closes a door in your mind and the more of those you close the darker your intellect gets until you are old and slow and unable to keep up with the changes of the world and of science.

Discovery HURTS but it is beautiful.
 

DM,

Sorry but I don't think you're following Prof. H's statement, outside the universe even at the moment of the BB, there is nothing, the "size" of the universe is at all times is infinite, you can not observe it from the outside to "measure" it because there is nothing outside of it. If you go there you will be g g g - gone! If you try to measure it from the inside you will be measuring it forever because it's always moving. Time matter and space all change relative to motion. When you're in the universe, the universe is "everywhere", so I agree, it is infinite.

Another way to look at it is, no matter where and how far we look in all directions, you are only looking back in time, you can not look at "now", you can't see where anything is, only where it was, relative to where we are now. So I'll suggest that we live in a universe of "time" not "space".

Dali,

Your stuff (and mine, I use a box) is NO-where ;)

Last, my personal quote to ponder:

You can't have nothing, if you don't have something.

Great Thread!

Where ever we go, there we are!

 But you're talking about perspective. While something might seem infinite from our perspective that doesn't mean that it actually is infinite, just that it appears so. If you were an ant walking on a mobius strip it might seem like you can never reach the end, but that is because the ant is traveling in limited dimensions.

 Instead of attacking the problem from our own limited perspective you have to look at it from the opposite viewpoint.

Lets say that an object was infinitely large. If it were truly infinite, it could not possibly grow any larger or smaller, because it would already have to be everywhere at once. This is a simple concept and it applies to our space time universe as well.

Because the universe is expanding I don't believe we can say it is infinitely large simply because we lack the means to reach or view it's edge. Neither can we say for sure that the universe is infinitely old or that it will exist forever because we don't know what was here before the big bang, or even what happened in the first few moments of the big bang because our laws of physics break down.

The void I'm talking about is more of a placeholder for what exists outside of our universe because nobody knows what exists outside of it. It's an abstract. But it's also very real since our universe exists inside of it and is growing in it.

I have to refer again back to the Hawkin's statement, "there is nothing outside of the universe". It really has nothing to do with perspective because there is no outside of the universe. The universe is in nothing. Alternate dimensions, which probably exist, are still within the universe. The universe if it is expanding, a point which I believed can be argued, is expanding into absolutely nothing. It does not "expand into something".

The poor little ant stuck on the mobius strip will at some point leave a "dropping" and after walking and walking will find the beginning of it's universe!

The argument that the universe is expanding is truely one of perspective it's what we can see, now. But, we at this point don't know anything about what is going on now, at the points in space where we currently see as a far back in time as we can. For all we know, those locations have been replaced by the "nothing". We can be fairly sure that the oldest galaxies we can see now, are not there, in the same place at this point in time. While scientists now believe in "dark energy" as the attractor, causing our "expansion" I believe that the "nothing" is in fact the attractor. When you get enough "nothing", matter is attracted and even created, hence the BB. Zero, divides into every number an infinite number of times, physics breaks down at the point of the BB because we are dealing with infinite values.

Perhaps we are on a "mobius strip of existance", with the universe continuously folding back on itself. (Doesn't that kind of follow string-theory?)

"Nothing" is not easy to grasp, it's why I have been saying for decades, "You can't have nothing, if you don't have something", it's the ancient concept of opposites. If we didn't have the universe as "something", there would be no "nothing" for it to be in. "Nothing" can't exist without "Something" including alternate dimensions.

I spent many years wondering, "but where is the universe" the answer is, the universe is nowhere, and it is everywhere... it is in infinity, and zero is a kind of infinity, imho..

I don't think my argument undermines Hawkings argument. Beyond our universe is a void. Nobody knows what is there, it's impossible for us to know what's there, so I use "void" as a placeholder. You could say a void is nothing, but nothing is something (to coin your wordplay).
 

I don't believe the universe is a mobius strip. And unfortunately as fantastic as string theory seems, it isn't science in my belief. It doesn't provide any useful insight into the world, make predictions, and it's not verifiable.  It's not testable.

 So back to perspective. Your argument is that our Universe is the only thing in existence. That everything that exists everywhere is inside our growing universe and it exists in space time. Would that be a correct phrasing?

Now the counter argument. If that ant were not on a mobius strip, but instead it were on the surface of a balloon that existed only in 2 dimensions, that ant would have no concept of up and down. It's entire existence has been spent in a 2 dimensional (3 if you count time) space and from it's perspective, it's entire universe would be one endlessly repeating journey where any starting point can be an ending point and another starting point over and over. Any direction you go you will eventually end up back at your starting point. Because from it's perspective it has no concept of depth. It's perspective and hence it's philosophy on the universe is limited.

 Try to imagine something you cannot imagine. You can't, so you use a placeholder. I can't comprehend how large the number 9x 10(10)(10) is in my head but I can write a note down on a piece of paper as a placeholder for that knowledge. What I mean to say is that we are limited in our conceptualization of the universe and what lays outside of it. We may never be able to prove or disprove alternate universes, dimensions, or realities but if we understand our limitations and examine the pitfalls of our own logic, we can sometimes figure out what we truly need to look for.

 
For example, if you assume the universe is infinite, you are no longer asking the right kind of questions.

Assume it is finite and then start thinking what that means. It changes everything we believe, and introduces new questions and questions are the marching feet of science. Questions like is ours the only universe? How would one detect other universes? What happens to gravity and light when they reach the edge of the universe? How long will our universe keep expanding? How old is it? What was here before the big bang? Were there more than 1 big bang?

For instance if gravity is a distortion of space time, there would be no gravity without space time, hence the void stops gravity in it's tracks meaning if there were other things in the void that were not a part of our universe they would not be drawn to or repelled from each other. If our universe were to collide with another, what would we observe? How would we be able to tell?

Once you have a few hundred of these types of questions lined up for future generations to ponder, maybe one of them will notice something nobody else has that can only be explained by answering one of those questions posed. And without that question nobody would have ever looked at it in that perspective.

I am trying to keep science fact a healthy distance away from science fiction so please understand I'm not a new age type looking for supernatural or mystical things. I think as scientists and as philosophers and as people, that we owe it to ourselves to never take things at face value. Question constantly.

 

When you suggest that there is anything, a void, other universes, or dimensions you are directly contradicting Hawking's statement, "there is nothing outside of the universe". Nothing is the non-existance of anything. "Nothing" only exists in our imagination, it's a concept, not a thing or a place. (Assuming of course that we do in fact exist :) Nothing is not "something" it's the opposite of something, but if "something" doesn't exist, then neither does "nothing" because there is no one to conceptualize it, hence "You can't have nothing, if you don't have something". It's much more than just wordplay.

I guess using "mobius strip" was a bad analogy, since it's only 1 dimensional, I meant a kind of "multidimensional" mobius strip (yes I know it's an oxymoron or something like that) but if you think of each dimension as a mobius, having no beginning and no end maybe that explains my thoughts better.

If for the sake of argument, I accept that there is a void, outside of our universe then the question first asked, must be asked again, "where is the void?" and where is the answer to that? It's a question to be asked and answered an infinite number of times. And when you consider that the "universe" is all things that exist, then whatever exists is part of our universe and cannot be considered as being outside of it, including other dimensions.

There can be only one answer, "The universe is everywhere, and perhaps more importantly,  the universe is nowhere." OhAncientOne 2008. Anyone may quote me.

None of this prevents the asking of any questions. No question is unimportant. To propose that there is a "right" kind of question is to limit the questions asked and that is just wrong. Are there other universes? Perhaps... some suggest that there are an infinite number of other universes encompassing every possible state of existance but, if they do exist, then by definition they are a part of our universe. (Anyone remember the book "Ring Around the Sun"?)

There is one question to me that should be at the top of the list and that is, how can we travel faster than light? Because I guarantee you, despite all that is currently known and accepted, it is in fact, possible.

Please know that the following is not meant to offend, but to reassure myself of my position, I looked this up: (note the word phenomena, which opens the door to all things)

Dictionary.com Unabridged (v 1.1)