Is the Universe Infinite? Theories and Considerations

[Physics-Learner]

in fact, as i think about it, the bounce and the big bang are not an either or.

in the bounce cosmology, the universe expands, and then shrinks back to a singularity, and then re-expands. the big bang and the re-expansion are basically one and the same thing.

 

[Tanelorn]

I also like the water cycle analogy where all the matter and energy is eventually removed from the universe eg. in black holes. Then some random event allows the energy back into the universe in the form of an inflatron or white hole. The pinball universe game is another analogy for this.

This of course is well beyond what the LCDM model and thus completely speculative.

 

[daniel rey m.]

You keep taking for granted that the "creation" of the Universe and the singularity at the "beginning" are certainties.

Some of us believe otherwise: that 1) it was "always" there because, once again, logic (which is all we have at present) shows that nothingness is nonexistent and thus nothing can appear out of nothingness , 2) there is such a thing as "timelessness", which is a mode of existence where all that exists is simultaneous and that is not accessible to analytical thought (and this underlies point 1 since timelessness implies no beginning and no end), and 3) "singularities" like the "cosmic seed" that expanded magically (it's almost like the bean in the "Jack and the Beanstalk" story, "mutatis mutandis"[there's your homework for tomorrow!]) and "black holes" are impossibilities since infinite density and zero magnitude (the quality of being a mathematical point) at a point in space would mean infinite gravitational pull, which would absorb the entire Universe, and this is not to be observed, at least in OUR neighborhood.

Your description of the Superuniverse shows that it's your fancy (but charming) name for what others call "the Creator" or "the Supreme Being". There's even a hint of reverence in the way you talk about It, so it's surprising that you refuse to use a capital ess for It. Next time you discuss It, kindly doff your hat, if you wear one, and take your shoes off, too, so as not to soil the ground --I mean "grind the soil"-- you're treading, like Moses before the burning bramble up on Mount Horeb (thought to be present-day Mount Sinai)….

 

[Physics-Learner]

i am not sure what you mean by a capital s ? yes, time decries that the universe had a beginning. singularity is just an idea. and i am not sure that everyone even agrees on what it is ?

the super universe is indeed the creator of this universe. whether it is controlled by a being or not is simply unknown and that information simply is not available to us.

your logic fails for the same reason that the second part of the kant argument fails. it assumes that one can apply our physical laws and thought processes to something that does not necessarily follow such processes.

there is no such thing as no beginning in time within our universe. the physical manifestation that we refer to as time had a beginning. if you choose to ignore the obvious, and believe that time had no beginning, that is your choice.

you obviously have biases that keep you from accepting things about our universe.

 

[Chronos]

The big picture is muddy. We have, on one hand, a model universe that emerged from a singularity. On the other hand, we have a bouncing model universe without a singularity. We currently have no observational evidence that excludes or affirms either idea.

 

[Physics-Learner]

and we arent ever going to get any observational evidence, either - LOL.

i am not too sure it makes too much difference whether the universe shrinks down to some Planck distance, and then re-expands. or it starts at a singularity, and then either expands forever or shrinks back down to a singularity.

the current universe would still have a beginning in time.

in neither case, could we definitely know that the same sort of universe would be created again. the next one might have different laws, etc.

once again, all we can learn about is what is in our current universe.

anytime we try to venture out into what i call the super universe, it is all just speculation.

i have my own thoughts about what might occur, just like i am sure that others have.

but none of it is testable.

 

[daniel rey m.]

This matter will remain as unfinished business so long as no one ponders the possibility that both sides could be partly right and that the truth is to be found somewhere in the middle, which happens often.

Our "Universe" would be as observed --expanding space-- but just one of an indefinite number of such stretched points, and the entire thing would be like fireworks going off in endless space. Each "universe" would be merely a spark, so that there would be sparks glowing, expanding and then vanishing all around us. We'd never be able to see beyond our own. Just as in ordinary fireworks, the sparks eventually would die down, but the bursts would keep coming and the show would never end. Only a Giant in charge of the show would be able to see it in its entirety. This Giant seems to be what they call "the Multiverse". It would have to be called the Fireworks Theory.

If that's the case then the term "universe" would be inadequate for the "sparks" since there are sundry and there is only one Universe, by definition (it means "all that exists").

It would be a mistake, then, to think that, since there is definite evidence for the expansion of space all around us, infinitude must be discarded, or that, since some of that evidence is weak, then the rest of the evidence must be an erroneous interpretation of the data.

The dark-nights argument is lame because in an infinite space, supposing there would also be an infinite amount of matter in it, then, just as there would be an infinite number of stars, so, too, there would be a matching amount of dust and gas, which means that any ray of light would eventually be reflected or absorbed, but apart from that one can imagine a finite amount of matter in an infinite extension.

The same goes for the redshift argument since "tired light" or some other unknown phenomenon is still a possibility. No one knows what can happen given an infinite time interval. The usual rules might no longer be applicable when dealing with eternity and infinitude. This can be seen in physics when trying to reckon the mass of an electron. One of its two components turns out to be infinite, which is impossible, so they ignore the infinite factor, they "renormalize" and then they get on with the reckonings.
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[Physics-Learner]

daniel,

i simply don't think our universe can have an infinite amount of anything.

infinite is simply an idea. it is not anything real.

how can we have both an infinite amount of space, and space that is still expanding ?

how can we have an infinite amount of anything ?

again, this only applies to our universe. i can't make any exacting statements about the multiverse, or super universe ?

infinite is not a countable number. it simply makes no sense to say there is an infinite amount of something.

 

[daniel rey m.]

Those comments show that both eternity and infinity are inherently paradoxical concepts, as I think I already said somewhere, but an infinite and eternal Uiniverse is just as inconceivable as its opposite since you can't have the Absolutely Everything impossibly placed within no context whatever except itself if it's finite. They've tried to go around this in strictly mathematical terms, by positing supposedly infinite universes that somehow wrap themselves around their own selves. There's no logical way out of the dilemma. I still don't understand how someone can be able to accept finitude but not its opposite, since both things are impossible to grasp and self-contradictory.
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[Physics-Learner]

i agree that neither eternity nor infinity are possible in our universe.

but i lost you on the remainder of what you said.

finite seems like an easy concept to grasp, in our universe.

 

[daniel rey m.]

Physics-Learner,

It looks like we'll never understand each other's notions because we seem to be speaking in different languages, but here's another attempt at it.

"Our universe" is a meaningless expression when implying that there are other universes because it would mean that there's more than "our universe", whereas the definition of "universe" is "the whole system of created things". Since you believe it's possible that there are other ones then what you're really saying is that our own cosmic environment, which you refer to as "our universe", is maybe only a tiny part of what exists, and you call all that exists "the Multiverse" or "the Superuniverse". By doing that you're evading the finite-infinite dilemma because if "our universe" is only a part of what exists then obviously it must be finite, but you don't face the problem of the nature of the Multiverse, and you turn your back on it conveniently by saying you can't say anything about it. However, that our neighborhood be finite doesn't necessarily mean it has to be temporary rather than eternal. It's just that you can't accept the idea of eternal duration (or infinite extension), but you do suggest that the unknowable All (Multiverse) could be eternal and infinite.

You also claim that "finite" is something easily understood, but you're unable to explain how there can be a barrier and nothing whatever beyond it. A barrier or limit implies that there is something on both sides. You can't have a wall or whatever you want to call it between something else and nothing. Imagine yourself right now beside that barrier, and imagine that you're touching it or trying to put your arm through it. If you could do that, would your arm disappear? Would you touch a rock-hard surface?

One could call that the Cosmic Agoraphobia Syndrome. Agoraphobia is the opposite of claustrophobia, in other words, a fear of wide open spaces. One can also say there's such a thing as "infiniphobia" or "eterniphobia". Infinity and eternity are disturbing because they're inconceivable, and whatever the mind can't grasp it discards and refuses to examine.

 

[George Jones]

I have closed this thread. The Cosmology forum is for the discussion of the professional science of cosmology, not for the discussion of philosophy, personal theory, and non-mainstream ideas.