Our Finite or Infinite Universe?

[mjr150]

I've given this a little thought and there is something else that I find puzzling. A point. It's infinitely small. What does that mean, well if you take the smallest measurable point in space, you can still imagine a point smaller that is comparable to a grain of sand as to the earth. And when you get down to that point, you can go smaller and smaller in the same way again and again forever.

How big space is can be can hypothetically be limited mathematically, but how small it can be is incomprehensible and has no limit that can be expressed mathematically to my knowledge.

 

[planetling]

SpeedFreek yes, of course I was referring to the observable universe, as I have responded in my previous post. Hopefully you have understood that if you read it in its entirety

Which previous post? The post I quoted from, which was your first in this thread, talks of the observable universe being absorbed into other surrounding universes (a very strange notion!), rather than the whole universe expanding and us only being able to see a small part of the whole universe.

I know that you are out to get me, so...you got me I should have been more clear so thanks for clarifying.

Yes it's a strange notion, but it certainly could be possible. Just as our solar system, and I presume others, have a heliosphere and oort cloud system, it would not be unreasonable to think that our universe has a similar, if slightly different system also. What is observable by current technology, beyond the observable universe could contain evidence that is so far away that it is undetected. Basically, I believe that as our universe expands, over time everything in it will eventually drift into other regions of a theoretical multi-verse. Think of many bubbles floating around, and our universe is one of those bubbles. And as one bubble [universe] breaks, others are being created.

This would also yield for a possible theory that 0 K can exist, somewhere in the voids between the many universes. I hope that you can follow what I am trying to say, and that it does not sound too preposterous. But then, there is no hard data that could expel this theory either

I also wanted to add that this is why I believe that our universe is finite (everything contained in it), even though it is in fact expanding.

 

[xXTheOneRavenXx]

My question has always been if the universe is expanding, what is it expanding into? If the answer is nothingness then that means nothing existed prior to the creation of it. But something had to exist for the universe to be initially created. You can't make something out of nothing. Same in reverse. If the universe were contracting, then what is left in the voided space? I understand the concept of nothing existing prior to the universe because time itself having not existed. Again, the same question remains. If nothing existed prior to the creation of the universe (including time) how is it that the universe came to be? If time itself did not exist, then nothing could have formed because everything takes time to develop, change, expand, contract, etc... I find myself perplexed by the very concept of the initial stages of the universe and the current theories because of this dilema.

Your questions are philosophical, not scientific. SpeedFreek's reply is concise and scientific: the laws of physics as we know them can't meaningfully describe events that took place less than 10^-43 seconds after the inaugurating instant of the "Big Bang". Likewise, we can know nothing about the nature of the unverse outside of our observable universe.

If it makes you feel better to speculate about what may have existed prior to the instant of the Big Bang then take your best guess. That's not science. To say "...But something had to exist for the universe to be initially created. You can't make something out of nothing..." is your rule, not Nature's rule. If you propose something that existed prior to the instant of the Big Bang, you then raise the question: What existed prior to that "something"?

If you want to imagine something outside our observable universe, you then raise the question: What lies outside of that "something"?

In short, we define our universe as everything and we define the Big Bang as the beginning of everything. You're perplexed because you're trying to imagine what lies beyond infinity and what is less than nothing. It's unlikely that anyone will ever find the answer to these questions.

Chris

I have to disagree with you csmyth3025. I believe any guess at the size, mass, etc... of the universe is scientific as well being only within our window of knowledge. Anything could in fact be possible given the complexities in what may have initiated the cosmic inflation from a possible singularity. Even recently the whole concept of red shift and what it represents have been put into question. In April José Francisco García proposed that "redshift in the light coming from the stars might be produced by the loss of energy of the photon with the time by emission of heat." So we could be completely wrong in our current understanding of the age of the universe, and all calculations within these long debates are scientific in nature. In my view we are only providing scientific guesses at the age of the universe. However it is intreguing when a new theory comes out that may explain some of what we see, or challenges current theories. A challenge isn't a bad thing in itself either. It will either help strengthen the theory, or disprove it and increase our current understanding, although it is still all speculation based upon the infantcey of our understanding of the cosmos.

The article from which I took the alternate explanation for the redshift is located at:
http://www.mrelativity.net/Papers/39/An ... dshift.pdf

It is a very interesting read, although the mathematics are above my current understanding.

 

[planetling]

A valid question to which I do not know the answer - Do electrons cease to move about the nucleus of an atom at absolute zero? Isn't temperature a means to measure energy released by moving matter? It seems to me that if electrons do move at absoute zero then it is not something that can ever be achieved. But this is not my field so I am going by gut instinct.

However, with this in mind and if I am correct, if we can assume that there is a place inside of an infinte void into which our universe has expanded then outside of this limit there is no matter. Without matter would not this be a place of absolute zero even though it could never be measured? Would our laws even apply here or do the laws only apply to that place into which our universe has occupied? I am not drawing a different conclusion than you I am just wondering if a temperature measurement is the right question to ask even though in doing so you have reached a supposition that I am not disagreeing with (although I don't know) that there is no real boundary and thus the unverse is infinite. But is is a fun exercise you've embarked on just the same.

This is pretty much what I believe. As I was reading your post, it occured to me that this could be one reason for FTL big bang, as 0 K would indicate lack of matter, outside or surrounding big bang, as we know it or can currently speculate it...there would be no medium whatsoever to prevent it from doing so (attain such speed)!

This (0 K) would also raise questions for FTL travel for those who believe that we may someday be able to do so???????? We may be able to pass through 0 K voids (either natural or someday manufactured) and attain any speed FTL without becoming toast! Well, it is fun to think about

 

[SpeedFreek]

So, here is my question:
Accepted theory now says that everything is accelerating as it moves away from the big bang. If this is the case, and we run things backwards to find the beginning, we would have to move everything slower and slower, the farther back we went. How then do we ever get to a beginning? It seems that we could never quite reach that point, but what do I know. Can anyone explain this for me?

Accepted theory says the universe was expanding incredibly fast to begin with, and that the rate of expansion was slowing for around 7 - 8 billion years, at which time the rate of expansion levelled out and then started to accelerate during the last 5 billion years.

 

[SpeedFreek]

The universe cannot be infinite in size as there was a Big Bang.

Yes it can.

http://www.astro.ucla.edu/~wright/infpoint.html

 

[SpeedFreek]

I've given this a little thought and there is something else that I find puzzling. A point. It's infinitely small. What does that mean, well if you take the smallest measurable point in space, you can still imagine a point smaller that is comparable to a grain of sand as to the earth. And when you get down to that point, you can go smaller and smaller in the same way again and again forever.

How big space is can be can hypothetically be limited mathematically, but how small it can be is incomprehensible and has no limit that can be expressed mathematically to my knowledge.

Yup. What happens, mathematically, is that you reach a singularity.

 

[SpeedFreek]

Think of many bubbles floating around, and our universe is one of those bubbles. And as one bubble [universe] breaks, others are being created.

Ok, thats fine, but bubbles do not move into other bubbles, do they?

 

[SpeedFreek]

Even recently the whole concept of red shift and what it represents have been put into question. In April José Francisco García proposed that "redshift in the light coming from the stars might be produced by the loss of energy of the photon with the time by emission of heat." So we could be completely wrong in our current understanding of the age of the universe, and all calculations within these long debates are scientific in nature. In my view we are only providing scientific guesses at the age of the universe. However it is intreguing when a new theory comes out that may explain some of what we see, or challenges current theories. A challenge isn't a bad thing in itself either. It will either help strengthen the theory, or disprove it and increase our current understanding, although it is still all speculation based upon the infantcey of our understanding of the cosmos.

The article from which I took the alternate explanation for the redshift is located at:
http://www.mrelativity.net/Papers/39/An ... dshift.pdf

It is a very interesting read, although the mathematics are above my current understanding.

We predict that, due to the expansion of the universe, a distant event will be observed to be time-dilated from our point of view. We have observed this time-dilation in the light curves (a measurement of the period of peak luminosity) in type Ia supenovae.

"Tired" light does not have an explanation for this, which is probably why that alternative explanation for redshift is languishing at a fringe website, rather than being published in a proper scientific journal.

 

[adharr]

Wow, this has sure been a lot of fun! Thanks for all your contributions. I'm still not sure I have an answer or that there even is one, but I do know that I need to go back to further studies and reading more of your references. Obviously, there are interesting mathematical constructs out there that seem to offer some sort of "definition" and there are lots and lots of very interesting ideas built around the latest advances and theories in astrophysics and cosmology. It seems there was one heck of a big happening several billion years ago that derived from some finite, but infinite source and expanded by some finite, but infinite time into some finite, but infinite space and included some finite, but infinite amount of energy and matter and some how we all managed to become a part of it. Perhaps I'm becoming a creationist!

Keep the good times rolling. I'm sure I'll check back now and then. Maybe in this thread or another one. It's been fun friends.

 

[Ruri]

I say the universe is finite but unbounded that in theory if you traveled long enough and fast enough you'll eventually end up where you started.
This is how Einstein described it.
But it's so incomprehensibly huge that even if we invent hyperdrives that could do several thousands of times c we'll never be able to cross it to prove that theory in practice.
It's present radius is at least 13.4 billion ly possible even larger if inflation theory is correct.

The multiverse on the other hand probably is infinite.

 

[dimasok]

The problem with the analogy with Earth is that we can look at Earth from the outside and see it's form and then assume that the universe is circular as well with no boundary and infinite walking in circles, but we can't see the universe from the outside but only from the inside so the analogy is really not good enough.

It's fair to ask what happened before the big bang and what is the universe expanding into because there aren't really any other analogies we can compare that too in order for these questions to cease being asked.

 

[MeteorWayne]

:roll: I get the distinct feeling this is now on the SDC front page

 

[dryson]

Welcome to SDC!

You are assuming there is such a thing as outside the universe. The implication is that there is space outside the universe but that it is devoid of energy and matter. The problem is that space by its very nature is full of energy and virtual particles as shown by QM and the uncertainty principle. For all intents and purposes there is no such thing as outside the uiverse.

I am going to have to say that this assuration is incorrect. Space is not full of energy but is rather a void that cannot interact or react to any type of energetic reaction or interaction. Unless you have atom's creating energetic reaction's or interaction's then there is no energy present. Space is a infinite vessel proveable by Pi.

There is no such thing as outside of the Universe but there is an outside of our Universe from which the center of the Big Bang eminated from where theoretically speaking Dark Matter is pulling our Universe away from the center of the Big Bang.

 

[Jerromy]

I am going to have to say that this assuration is incorrect. Space is not full of energy but is rather a void that cannot interact or react to any type of energetic reaction or interaction. Unless you have atom's creating energetic reaction's or interaction's then there is no energy present. Space is a infinite vessel proveable by Pi.

There is no such thing as outside of the Universe but there is an outside of our Universe from which the center of the Big Bang eminated from where theoretically speaking Dark Matter is pulling our Universe away from the center of the Big Bang.

A. there is no apostrophe's (<- see wrong) when showing plural, only for posession.
B. the big bang was never intended to represent a "center" from which everything "exploded" away from.
C. space IS probably full of energy (and matter) since nowhere has been observed to be void of it.
D. dark matter would make no sense in the respect that you represent it as "pulling" the known universe away from an "imaginary" center.

 

[csmyth3025]

...Space is a infinite vessel proveable by Pi...

I'm not familiar with this proof - please provide details.

Chris

 

[xXTheOneRavenXx]

C. space IS probably full of energy (and matter) since nowhere has been observed to be void of it.

I hate to be the one to correct you Jerromy, however there has been voids discovered in space. The largest being a billion light years across. This "cold spot" was first detected using the WMAP and later verified by Lawrence Rudnick and colleagues of the University of Minnesota using the VLA radio telescope.

http://www.space.com/scienceastronomy/070823_huge_hole.html
The article was also released a day later on New Scientist.com:
http://www.newscientist.com/article...in-space-is-1-billion-light-years-across.html

This subject was also written in a paper on arxiv.org and various other websites. That is the one that really stuck out because of it being the largest. However there has been others detected before.

 

[csmyth3025]

C. space IS probably full of energy (and matter) since nowhere has been observed to be void of it.

I hate to be the one to correct you Jerromy, however there has been voids discovered in space. The largest being a billion light years across. This "cold spot" was first detected using the WMAP and later verified by Lawrence Rudnick and colleagues of the University of Minnesota using the VLA radio telescope.

http://www.space.com/scienceastronomy/070823_huge_hole.html

Please note that the SDC article contains the following quote:

"Although our surprising results need independent confirmation, the slightly colder temperature of the CMB in this region appears to be caused by a huge hole devoid of nearly all matter roughly 6 to 10 billion light-years from Earth," Rudnick said

This statement tells me that the void you refer to is nearly devoid of all matter and that it's suffused with the (slightly colder temperature) CMB. This doesn't contradict Jerromy's statement.

Chris

 

[MeteorWayne]

Yes, that statement implies there is nothing there....that's just silly. The density of matter is lower there than elsewhere...that's all it says. A good vacuum by earth standards, but certainly not empty.

 

[yevaud]

Due to Quantum fluctuations, no point in space can be truly said to be devoid of anything.

 

[xXTheOneRavenXx]

Due to Quantum fluctuations, no point in space can be truly said to be devoid of anything.

What about Paramhamsa Tewari's Space Vortex theory? (former Executive Nuclear Director, Nuclear Power Corporation, Department of Atomic Energy, India) "In Tewari’s theory space does not vary in density, rather space has continuity without interruption except where voids in space are formed by the high-speed circulation of space fluid which causes a tear and a void. It is these vortices surrounding voids that form particles in his Space Vortex theory."

http://www.astrosciences.info/FlowGrav.html

Again, the math is beyond my understanding, however the paper interested me because of my interest in space and my understanding of his prediction. I am presuming that Tewari's SVT predicts that space does contain voids. However he does point out the current theory:

"Until tests can be devised to select among these hypotheses, none are favored as yet. What is suggested, in common, is the nature of space and that space itself is not a void or nothingness, but consists of a fine energy-substance the nature of which is not yet clear. This idea is similar to the older ether theories of the nineteenth and twentieth centuries but differs from the older theories in several important aspects that are intended to resolve the discrepancies and shortcomings of the older theories. The rationale behind postulating further on the subject of gravity is twofold: one is the irreconcilability of General Relativity with quantum gravity theories, and the second is the lack of understanding on just what gravity is and how it can be harnessed as a force in terms of human engineering."

His debate is with the current theories and it appears he seeks to have them revisited. yevaud have you seen any peer-reviewed sights which have debated his SVT? since it was written in 2004. If his theory could be proven, then from what I gather, it would predict regions of space void of mass & energy.

 

[FreeThinkingAnarchist]

Could it be that the edge of our universe is in a higher dimension than ours? Perhaps fourth, fifth, six......

 

[yevaud]

You know, Raven I actually hadn't seen/read of any abstracts on this hypothesis. It's not entirely unfamiliar to me - it contains elements of other hypothesis' I have read - but nothing on this in specific, no. Sorry.

 

[xXTheOneRavenXx]

No worries. I read a lot of things on the net in regards to my interest in space. I do try to stay away from the woo-woo sites. So when we get on a topic such as this I tend to throw in an article or two I have read. It is just fascinating how big the universe is and how small our understanding of it is.