Is the Universe Infinite?
 

I've been occasionally watching this series on TV called "Finding God thru Faith and Reason". I have a hard time following most of it. But he presented the idea that "we now know the Universe is not infinite". I didn't know that was common knowledge. :) I also encountered that same belief in Maimonides' Guide for the Perplexed. Or at least I think that's what Maimonides is saying. I think he uses the word "transcendent and eternal".
But believeing that the Universe is finite seems to have some strong linkage back to a belief in God. I find that strange because I grew up with a strong Christian upbringing and was taught that the universe is infinite.
Any ideas on this and why a finite universe might provide a better case for there being a God?

I think a lot of people are proceeding on the assumption that was behind what the Rambam (Maimonides-- Rambam is his acronym in Hebrew, Rabbi Moshe Ben Maimon) was saying: that if the universe were truly infinite in both space and time, God could not be transcendent, but would inevitable have to be entirely "within" the universe and in no way "without."

A key philosophical problem has always been God's existence independent of the universe, and what that implies as to what might be "outside" the universe, or "outside" the scope of Time. Especially in the Rambam's day, there was a strong contingent of philosophers who maintained that all matter in the universe was eternal and uncreated. They felt strongly that to imply otherwise was both irrational and created many philosophical problems that were likely to be insoluble. The Rambam, whose raison d'etre was the attempt to fuse Jewish theology and philosophy with neo-Aristotelianism, was put in the difficult position of having to maintain that the universe was more or less eternal [as close to the neo-Aristotelian view as he could get], but that God created the universe ex nihilo [the position of the Jewish tradition]. By definition, then, God would have to be transcendent, with an existence independent of the universe, which means that there would have to be something "without," both in terms of space and time.

If I have correctly identified the passage you mean, in Hebrew, what Rambam says in Moreh Nevukhim (The Guide for the Perplexed) is that the universe is "ha-olam ha-nivrah olami hu, u'malkhut yotzro l'olam va-ed." "The created world is eternal [literally, 'is as long as the life of the world,' a common euphemism in classical Hebrew for eternality], but the rule [that is, the span or existence] of its Creator is beyond eternal." Or, to put it in more modern terms, the universe exists for or in what is to us, to all practical purposes, a nearly infinite amount of time, and in a nearly infinite amount of space; but for God, the finiteness of that space and time serves to accentuate His infinity and transcendence. (It would be damned handy at this juncture if I spoke Arabic, since that's what the Guide was originally written in, and all the Hebrew translations are known to have some idiomatic shifts....)

The problem with God being transcendent is that one either has to wonder whether God has to split himself up in order to get himself into the finite universe [which seems, in part, to be Christianity's trinitarian contention], or whether God is entirely outside of the universe [the theology of Rabbi Isaac Luria's neo-Zoharic Kabbalah], or if something in between, where is the "center" of God. The Rambam in part solves this by postulating God as an almost abstract Causa Prima, the ultimate agglomerated source of intelligibles; His presence in the universe is in the form of Shefa, outpoured radiance [probably what Rambam meant by this is mostly like primal lifeforce, basic energy]. In a way, Rambam's God is a little like a cross between the Hindu Brahman and The Force. To be honest, from my point of view, I find it a very unsatisfying theology for Judaism, but then, I'm not a rationalist.

I do actually think it rather makes our theological lives easier that it turns out the universe is not, in fact, infinite or eternal. Doesn't answer any questions, really, but it gives us a bit of breathing room. If the universe were infinite in space and time, but continuously expanding, as astronomy seems to indicate to us, we might be forced to ask, "where within the universe could we locate God? Or if not all of God, at least the 'center' of God?" And that is a deeply problematic question. Moreover, what would we do with the fact that an infinite and eternal universe that is continuously expanding, but contains a finite amount of created matter, is inevitably going to come to the point at which all matter is spread so thin that nothing complex can exist anymore. And since we postulate that God created the universe at least in part in order to sustain complex beings, what would God's purpose be in creating an infinite system that inevitably fails one of its prime purposes? If you raise the same question with a finite universe, saying that if a prime purpose of the universe is to sustain complex beings, and yet it will end altogether in another 15-20 billion years, one could respond by saying that a transcendent God-- unaffected by the demise of the created universe-- could well create another, which is a valid philosophical answer.

You see what I mean?

I guess it depends on what you consider to be the universe. As you may have heard the universe was supposedly created from a big bang, and is thus expanding. You cant expand if you're infinite. Astronomers have seen pretty far out, nearly to the edge of this expansion but can never see the edge due to its properties (lack of light for visibility).

The universe is expanding.. so that means it is probable that it is expanding into something. What it is expanding into and how far that something extends, no one knows. And is what the universe is expanding into also considered the universe? or is it something else?

If you really want your mind blown you should look into the theories that the universe is a giant hologram. Part of that theory suggests that every part of the universe is contained within every part of the universe. So for example inside a strand of hair is an infinite number of universes.. all of those universes being THIS universe.

I do understand what you mean Levite. Thanks for the great explanation and I appreciate your knowledge and perspective on Rambam's philosophy. The Guide is a fairly difficult read for me.
Obie offers a more secular response which I also appreciate. Although I haven't got my head around how an infinite number of universes can all be this universe. Can you draw me a picture? :)

For us yes.

If you could get a magical space ship that could travel faster than the speed of light, and could catch up to the edge of the expanding universe, you would never reach an end.

In our 3d world it would go on forever.

Now some clever theoretical math types can start to talk about curved space, and extra dimensions, where what seems like straight line 3D travel is really curved, a sort of Mobius strip with an extra dimension, to us its meaningless, and at this point mostly untestable.

Hell one theory I read is that objects create their own space, so if that were true, the Universe would be finitely infinite.

instead of drawing i thought i would just link this lol.

Universe is finite. For analogy take example of earth :

Is earth's surface finite ?: Yes. But if you keep on walking you will never reach the edge. you will reach the same place ! (does not sound exciting now but believe few 100 yrs ago it was marvellous idea and anti-God)
Point is: In 3D space walking on 2D surface (of some geometry) can make it feel infinite.

Similarly if you go straight in space you will never reach its edge but come back to same point. As space is 4D (may have higher D) and our 3D travels look like infinite.

(Well for that you will have to travel with something like speed of light and many other constrains)

Just a sec... I'm looking up the Koran on this.

Skada - I have a hard time comprehending 4D but I'm trying. If I travel straight in space and come back to the same point, it seems to me that all I would have done is define the finite "surface" of that space. I've proven that space is finite, but I haven't proven that the universe is finite. Because, the universe would have to encompass even that which lays outside the surface of that space.
I realize that you're not wrong and I'm not trying to be right. Maybe we're working from different definitions of "universe".

If the universe is finite in time, then the question of "what comes before" could lead one to saying "god"?

The misunderstanding that "just because X is infinite, there is no room for other things" probably comes from a lack of understanding of how to manipulate infinity. A 3 dimensional space and 4th dimension time universe of infinite extent in all directions can be embedded in, say, a Hilbert space which contains an infinite number of dimensions.

Stick your god into the Hilbert space, and our universe takes up less "room" than a single dimensionless instant spec takes up in our universe.

So... "the universe is infinite" doesn't really provide any problems creating a structure that contains the universe, and is much much larger. The understanding of how to deal with infinities we have today are pretty decent.

...

"If the universe is expanding, where it is expanding into?"

Imagine every fraction, a/b, such that b isn't zero, and both a and b are positive counting numbers (1, 2, 3, 4, etc). You could understand how that describes a collection of stuff?

Now take that collection of stuff, and double every number in it.

What happens? Well, if you take any two things from the original set, look how far away they are from each other, and then look what happens when you double both -- you end up with them being twice as far away from each other!

In a sense, we expanded the collection of stuff. But we expanded it into itself. There was no "gap" at the end of the numbers that we expanded it into. Every number was doubled from a/b to 2a/b -- which was a number that was also in the collection!

And we left no room at the bottom. For every number c/d in the "after" collection of stuff, the number c/2d was in the "before" collection of stuff. And c/2d * 2 = c/d.

This trick was worked out in, I think the 17th century? I think it was a guy called Bolzano, but it might have been Weirstrauss (sorry if I got the spelling wrong).

In effect, if you have an infinitely long line, that line can expand by any factor into itself, without expanding into anything.

You can do similar tricks if you have a line that "loops back" on itself, like those mentioned above. The line can get "twice as long" without having anywhere else to expand into.

In short: theologists aren't mathematicians. So they sometimes get hung up on "infinity", and don't have the tools to play with it. The infinite universe "left no room for god!", so "knowing the universe is finite meant we can have god". As demonstrated, you can create an infinite universe in time and space that has plenty of room for god. Heck, there is plenty of theological room for an uncountable number of universes, if you want it.

I think Yaak hit it - its just too difficult for humans to comprehend "infinite"...the fact that there is even conjecture about "time" and "what is the universe expanding into" proves that.

Infinite is just that - infinite. There are no bounds -"this"/"that", "here"/"there", "now"/"then" (time) have no meaning in an infinite system, there are no reference points other than what we assign for our own feeble understanding.

Last time I checked, most organized religions assigned their "God" figure the same properties -omnipotence, omnipresence, omniscience, etc. Why so much faith in these properties and such difficulty in perceiving the infinite universe?

Hence my own view that we are merely a means for "all that there is" or "God" to perceive itself...without us there would be no reference point or consiousness of what "is" and what "is not".

my fave simpsons intro of all time.

reminds me of a filmclip used by a band i saw heaps live that starts with a man on a rowboat and ends with something like that image from hubble with all the galaxies then returns to the guy on the boat but continues in and ends with the contents of an atom. if you know what i´m talking about i´m desperately trying to track down that clip...

to the point.

i´ve chosen to colour in the picture my way to make my life easy and have one theory which may or may not work but it seems to for me. we seem pretty certain about the big bang. ok. i´m happy with that and can run with it. what was before the big bang? i don´t think god clapped his hands together (god always seems to be a he - pretty obvious the sex of the people writing religion...) so could the reverse have happened? ie the big contraction. now for the contraction to happen matter had to be spread out. kinda sounds like the result of the big bang! ok so there are details like how can we be accelerating etc but in simple form it does work: bang, matter moves away from each other like in any explosion, force of gravity (i´m near certain this is only the bond force between atoms and molecules) always acts and the momentum of the explosion runs out one day and gravity strats pulling everything back in until it reaches a singularity or close to and the big bang happens. again. this leads to 2 possibilities: the big bang is perfect, ie this moment of me typing this and you reading this happens at a set time and has happened an infinite number of times before now and will happen again infinitely into the future. the other posibility is that the big bang is inperfect and everything is different each time around but since this has been going on infinitely every possibility has already been exhausted infinitely. hell this moment has happened except immediately after posting this i turned purple and gravity inverted. statistically, given infinite possibility this has happened at least once! BUT, given infinite possibility, this moment has played itself out exactly this way an infinite number of times as well. as for what the universe is expanding into i just think of empty space as given the force of gravity all matter finds all other matter no matter how far away. just my thought :)

Is time infinite?

maybe