What Is Beyond The Observable Universe?

[Tojen]

ianthow,

There's a distinct odour of New Age-ism in your post. New Age "ideas" denigrate, at the same time, science ("we have to think beyond science") and religion ("the someONE or someTHING who created us prevent us from thinking beyond") to pave the way for its own agenda ("The answer might lie beyond the logic, reasoning and science...").

 

[patrik75]

Could it be that it is not a relevant question to ask? I am thinking of entanglement and distance as an "illusion". Right or wrong?

 

[Soul Surfer]

We may not be able to see directly or measure the properties of anything outside our observable universe but we can predict potential properies based on the fact that is probably made of the same "stuff" that our observable universe is made of. Bearing in mind of course that conditions may well exist where the current physical constants we observe may be tweaked a bit.

Or actual universe may well extend a long way beyond our observable universe but there is strong evidence that it had some sort of beginning, is evolving and changing with time and will eventually have an end.

This suggests that our universe is likely to be a finite object in a "multiverse" of indefinite extent.

We also have strong evidence that there are separate "universes" budding from our universe in the form of black holes. This tends to strengthen this feeling that multiple universes exist.

This makes me favour an overall fractal structure for the multiverse in which the laws of physics have evolved to produce maximum numbers of structures of maximum longevity following the general rules of "evolutionary metaphysics".

You can find a bit more about this on my website but the basic thinking behind "evolutionary metaphysics" is to look at the processes that would operate in any system with physical laws, to create complexity by exploiting metastable and recycling processes to extend the life of what would otherwise be only transient and random intereactions.

 

[SpaceTiger]

We also have strong evidence that there are separate "universes" budding from our universe in the form of black holes. This tends to strengthen this feeling that multiple universes exist.

What evidence is that? Last I heard, that was only speculation.

 

[Soul Surfer]

The evidence is purely in the properties of the object. Any activities inside an independant universe can by definition never be observable from our universe. All that can be done is theoretical modelling which is not subject to such barriers.

A black hole is a construct into which mass may pass and we will not be able to observe it altough it does have still an effect in the form of a gravitational field in our universe.

It is true that once our universe has cooled down sufficiently (a long time from now) the black hole will start to evaporate very slowly and will eventually vanish but the time that even a stellar mass black hole will take to do this is very many orders of magnitude longer than the current age of our universe.

Anything inside the hole will not be able to see out and will be largely unaware of the size of the space because the gravitiational field will tend to distort things so it looks very much larger. OK there may be a certain amount of high energy inflow from outside in the form of things that look like cosmic rays. but their source will not be detectable.

If that isn't a specification for an independant universe I don't know what is!

OK I will concede that it may well be possible to measure that the space is finite and see a retreating set of echoes of one's self at greater and greater distances like looking into a set of parallel mirrors but since when has that been a bar to declaring a universe. I am aware of at least three occasions in cosmology over the last hundred years or so when there was serious consideration that we might be able to do something like this in our universe (one of them is around now)!

 

[SpaceTiger]

The evidence is purely in the properties of the object. Any activities inside an independant universe can by definition never be observable from our universe. All that can be done is theoretical modelling which is not subject to such barriers.

Anything for which there is no observational test falls into the realm of philosophy and using words like "evidence" here is deceptive.

Perhaps pervect can give more detail, but to the best of my knowledge, the standard model of the universe and the standard model of a black hole are not compatible with one another unless one invokes a wormhole connection, which is in itself a matter of pure speculation.

A black hole is a construct into which mass may pass and we will not be able to observe it altough it does have still an effect in the form of a gravitational field in our universe.

The standard definition of a black hole gives it only three properties: charge, mass, and spin. The only property we think we've been able to measure so far (for some black holes) is mass. These measurements don't tell us anything about whether or not the black hole has spawned a new universe.

It is true that once our universe has cooled down sufficiently (a long time from now) it will start to evaporate very slowly and will eventually vanish

Based on what? An extrapolation of \Lambda CDM? There's no reason to think that the current model of the universe will be good for all time.

If that isn't a specification for an independant universe I don't know what is!

You've granted black holes and our universe several rather arbitrary properties in the process of getting there.

Is it possible that the formation of a black hole spawns a new universe? Sure! Is there any evidence for it? No. At this point, it's pure speculation -- it doesn't come naturally from standard theory and it hasn't made any predictions that have been confirmed by experiment.

 

[Soul Surfer]

How then do YOU define the properites of an independant universe?

Of course this is pure speculation the original question posed here was one that could only be answered with pure speculation because it dealt only with unobservables.

Mathematical modelling is a perfectly acceptable approach to coping with unobservables our current cosmological understanding is strongly dependant on using the matematival modelling of galaxy strucures and clustering to "prove" that our theories about the composition of the universe fit what we observe

 

[Soul Surfer]

Note I tend to use the term our universe to mean everything that we can observe and strongly infer (like areas hidden by inflation) and the multiverse to mean everything there is.

I personally favour a multiverse that obeys the perfect cosmological principle it that on a large enough scale it is generally similar for all time and space and has evolved to be so. it contains very many evolving universes (like our own) at all stages of development and is probably fractally structured.

I would strongly prefer to end up with an aspect of scale invariance in which the space and time were a property of the universe and the inside of a budding univese was of indefinite size to those who were inside it.

 

[SpaceTiger]

How then do YOU define the properites of an independant universe?

I'm not bickering with your definition of "independent universe", I'm bickering with what seemed to be a claim that there is observational evidence for them. If you acknowledge it as speculation then I have no quarrel.

 

[Silverbackman]

How could a black hole "spawn" another universe? I would think it would lead to another universe perhaps? And who is to say black holes in other universes are like our own. Yes it is speculation at the moment.

 

[Arian]

You guys, here are a few points
1. Space is not Infinite.
2.There is a high, high high probabiltiy of life
THe point is, if we can't see it, somebody else probaby can.
The universe is also looped, this means that if you go infinitly in one direction you will come back to one place again and again.BUt this can never happen because the universe expands way faster then the speed of light, but you can't go faster then the speed of light.
Its like the Earth exapnding really fast to a point that you can't actually ever go around it.

 

[matt.o]

You guys, here are a few points
1. Space is not Infinite.

How do you know? Which measurements prove this?

2.There is a high, high high probabiltiy of life

Obviously, we are here. But what is the probability of life in other solar systems? Have you worked this out?

The universe is also looped, this means that if you go infinitly in one direction you will come back to one place again and again.BUt this can never happen because the universe expands way faster then the speed of light, but you can't go faster then the speed of light.
Its like the Earth exapnding really fast to a point that you can't actually ever go around it.

Again, how do you know the universe is "looped"?

You have stated things as fact that are far from fact.

 

[kmarinas86]

You guys, here are a few points
1. Space is not Infinite.
2.There is a high, high high probabiltiy of life
THe point is, if we can't see it, somebody else probaby can.
The universe is also looped, this means that if you go infinitly in one direction you will come back to one place again and again.BUt this can never happen because the universe expands way faster then the speed of light, but you can't go faster then the speed of light.
Its like the Earth exapnding really fast to a point that you can't actually ever go around it.

When you think like you finally know the truth, your research suffers.

 

[Garth]

Hi Arian and welcome to these Forums!

You may think your post has been replied to rather brusquely. If you had put your points of view as a series of questions then you would have received some thoughtful and helpful answers. They may have led to an interesting discusssion, however there are others here who do know the subject in depth and rash or false assertions are countered quickly.

Keep asking questions and you will learn.

Garth

 

[Silverbackman]

Regarding the shape of the universe, most evidence shows that it is flat (at least the curvature).

 

[CosmologyHobbyist]

Is there any chance that the big bang was a quantum event? If so, wouldn't that require quantum field to pre-exist the universe? If that is the case, doesn't quantum field provide possibility for pre-BB space and time? Is quantum-event BB still a valid theory, or is it gone for some reason?

 

[Garth]

Is there any chance that the big bang was a quantum event? If so, wouldn't that require quantum field to pre-exist the universe? If that is the case, doesn't quantum field provide possibility for pre-BB space and time? Is quantum-event BB still a valid theory, or is it gone for some reason?

Yes!

[But we have to wait for a tested quantum gravity theory to be sure.]

Garth

 

[Flatland]

String Theory actually claims to explain what happened before the BB.

 

[Chronos]

String Theory actually claims to explain what happened before the BB.

Re-review what matt.o had to say. I think you are hopelessly deluded. String theory predicts . . . not a damn thing. Feel free to to contradict that assertion with . . . a testable prediction. I love those things.

 

[wolram]

I think some one has just put a paper in about the (bouncing) universe,so
if he is correct there never was a begining, and it may be possible to see
beyond the BB, the paper may be in arxives by now.

 

[Balence]

Its impossible to know exactly. We can speculate their are more stars and galaxies out there, and other things we would expect to find in the known universe. Its possible that if you went so far into the universe that you may find a place that is a duplicate, seeing as odds make no difference when looking at infinity.

 

[callistoite]

I have a simple answer.

We don't know "yet"

 

[Tapeworm69]

Okay. There is obviously no answer to this question... YET!
I think philosophically we have to assume both that there is both, something "beyond" our universe and that there also is nothing. You must assume both, seeing as you know neither to be true or false. Get it?

 

[Sorry!]

Ok I have been trying to bend my mind around the whole there is nothing outside our universe (as in we can not know ever) But on the first page I read an analogy of a Sphere what's outside a sphere.. can anyone explain this to me?>

 

[squidsoft]

Suppose we lived in sum world:

\sum_{n=1}^{\infty} \frac{1}{n^s}

and we asked, "what is outside of sum world?". We know if we go far enough, sum world reaches a singularity (it diverges). But is there anything beyond that singularity? Is there something larger that encompasses sum world and reduces down to it when certain conditions are met? Of course the answer is yes: zeta world. How is zeta world different than sum world? We certainly can't use the same "methods" (convergent sums) of sum world to describe zeta world. The two worlds are qualitatively different but zeta world contains sum world and can completely describe sum world using zeta methods (a contour integral). How did we get to zeta methods? How can we get to those methods which can describe our Universe as well as the larger world for which ours is only a particular instantiation?

 

[callistoite]

Well.. c'mon guys. let's take it easy..
Forget about we being the tiny little human beings on this small planet that we call "earth".
Suppose we are BIG in size. about 10s of billions of times Bigger than the observable universe, that we even have to use microscopic equipments to actually see a galaxy floating in the empty space, it will take billions of light years for an earthling to travel from your toe to head. an earthling will be much much smaller than an "atom" - if we call it that way - on your body.

In that size, if you look around, what can you see?
Okay, just for a change, shall we not talk about philosophy and add a little bit of creative, sci-fiction like thought?

 

[DaveC426913]

If, instead of being here in the Milky Way, we are actually 11 billion light years away in a different galaxy, we're still going to see a universe that is homogenous in every direction. We're not going to look one way and see a giant black void. If we did, it would be because the universe is not homogenous at large scales, that there is and edge and there is a centre.

So, what's beyond our observable universe is more, similar universe.

We can't ever see it, but we can deduce it.

 

[_____A-L-E-X_____]

I wonder how the recent "discovery" of dark flow plays into all this-- what if what's just beyond the visible universe can gravitationally affect that which is just within?

 

[ray b]

there be dragons

at least that's what the old maps said
about the areas as yet unexplored

 

[Hal King]

That's the wonderful thing about cosmology -- fantastic possibilities and predictions -- most of which can never be proved wrong!

Just for the fun of it, I calculated -- using the current model I'm playing with -- how much the observable universe makes of the total amount that 'must' exist NOW due to the Cosmological Principle.

Answer was: 39.349307% meaning the other 60.650693% we can't see -- but by the Cosmological Principle should be more of the same. By this model it turns out that this percentage doesn't change -- but the universe just keeps getting bigger.

In order to get a limit I had to ASSUME that the photons did NOT travel backward in time on their way to us -- regrettable.

There were several other assumptions -- like ONLY considering matter as 'something to see' and a value for the expansion velocity for matter (0.8660254 of the speed of light). Nothing important.

Now I'm sure everyone feels much better knowing this.

 

[Chronos]

An interesting proposition, and unsupported. Do you have any papers in mind? Your calculations appear to be a naive solution to the Friedmann equation.

 

[keepitmoving]

more of the same.

 

[Onslaught]

I know that this is a physics forum but just because physics can't explain the proposed question in totality doesn't mean you can't have some insight into a possible solution.

I doubt that the questioner wanted an exact answer. You should let your imagination explore these ideas sometime. Who knows what someone with your knowledge in physics might come up with. I bet you could come up with better answers than were given in this thread.

Just because you don't have an answer doesn't mean you shouldn't try to answer.

 

[Cryptonic]

I know that this is a physics forum but just because physics can't explain the proposed question in totality doesn't mean you can't have some insight into a possible solution.

I doubt that the questioner wanted an exact answer. You should let your imagination explore these ideas sometime. Who knows what someone with your knowledge in physics might come up with. I bet you could come up with better answers than were given in this thread.

Just because you don't have an answer doesn't mean you shouldn't try to answer.

Nah they don't like that here, I have learned. Just another bastion of closed-minded reactionism, like the horrible bautforum.

 

[Onslaught]

I was also wondering what people thought about poincare dodecahedral space. I haven't found any papers refuting this theory about the shape of space. Especially with the recent WMAP data.

 

[Chronos]

The dodecahedral proposition is weak. See, for example:
Dodecahedral topology fails to explain quadrupole-octupole alignment
http://arxiv.org/abs/astro-ph/0611640

 

[Onslaught]

Thanks for the link, thought it sounded to good to be true.

I find it impossible to comprehend a universe that is infinite, because no matter how you try to explain it, it HAS to end somewhere. Even if you use the balloon analogy that's like saying walking on a straight path on Earth will bring you back to where you started. However if you take a rocket at escape velocity you can go beyond this.

Should there be a way, no matter how inconceivable, to escape from this so called Universe. i.e. an escape velocity for our Universe?

 

[Chronos]

By most models, the speed of light is the escape velocity of this universe. That is obviously impossible to achieve. It is unclear if the universe is finite. I tend to think it is from a strictly observational standpoint - e.g.. Olber's paradox. There may be 'stuff' outside our universe but I see no possible way to confirm this by observation,

 

[danda22]

hmm. a very hard question to consider with no definite answers.

i tend to believe that there is nothing outside our universe. just... nothing

btw. even if youu were traveling at lightspeed you could never escape"" or even reach anywhere near the edge of our universe. (the furtherst particle away from the "middle")
simply because it is also expanding at the speed of light.

 

[DaveC426913]

hmm. a very hard question to consider with no definite answers.

i tend to believe that there is nothing outside our universe. just... nothing

btw. even if youu were traveling at lightspeed you could never escape"" or even reach anywhere near the edge of our universe. (the furtherst particle away from the "middle")
simply because it is also expanding at the speed of light.

The universe has no middle. The universe has no edge.

The best model that shows how this can be so is that the universe is curved and closed. A 4-spatial-dimensional sphere.

Travel in any direction long enough and you will arrive back at your starting point.

 

[cfung]

This is what I know about the structure of the universe.

In our universe there are 2 parts. The observable part, like many have said, is +/-13.7 billions light years long. Then outside the observable you've got the unobservable part of the universe.

It's unobservable simply because light isn't catching up with the speed at which the universe expands. The distance between the edge of the universe and the light that's trying to reach the edge of the universe is what we meant by unobservable universe.

In other words, the universe is being expanded and light is trying to fill in and cover the created space-time, but the space-time being created is faster than what light can cover, so there is always an unobservable part of the universe where light hasn't reach.

But even without light, this unilluminated space-time obeys the laws of physics, it's nothing more than space without light. With that said, the unobservable universe is existing and so it's relevant that we understand what it is.

However, what's outside the edge of our expanding universe? There could be something like a higher dimension or a turtleback, though as much as there is a possibility of something outside, there's an equal chance that there is non-existence (if existence involves space-time). But if you want a correct answer to the question, what's outside the edge of the universe, the answer would be: there is the edge of our universe.

Many who understands often label the question pointless to ask, since one is asked to describe an object that is non-existing in the world.
Likewise if there's a non-existing object called Mr.X, how would you describe Mr.X to me? Seriously, try answering that until you get a sense of impossibility.

To see how it's unanswerable, Steven Hawking once rephrase such questions along the following: What is north of North Pole? North Pole, probably.

 

[Chronos]

Our universe could be embedded in an infinitely large 'void', but, I fail to see how that helps us understand the universe. It would also raise issues like why matter occupies just an infinitesimal volume in all that can be characterized as 'spacetime'. Creepy. Cosmology is hard enough as is. All we can say with any certainty at present is the universe is observationally finite. That may not be all there is to it, but, it is all we can hope to describe for now. Better theories may give us new perspectives, but, better observations would raise my comfort level more quickly.

 

[ray b]

The universe has no middle. The universe has no edge.

The best model that shows how this can be so is that the universe is curved and closed. A 4-spatial-dimensional sphere.

Travel in any direction long enough and you will arrive back at your starting point.

do you have any proof of that last statement ??

 

[DaveC426913]

do you have any proof of that last statement ??

No, I'm not stating it is so, I'm stating there exists a model of the universe with this geometry.

 

[diogenesNY]

The universe has no middle. ...[edit]...

But Dave, isn't it _all_ middle? :)

diogenesNY

 

[DaveC426913]

But Dave, isn't it _all_ middle? :)

diogenesNY

Sure, that too.

But of course, 'middle' is only meaningful inasmuch as it is distinguishable from every other point; it is unique.

If it is all middle, then it is not unique.


To modify your statement: it all was middle.

 

[diogenesNY]

Sure, that too.

[edit]

To modify your statement: it all was middle.

A point lucidly made, well taken, and appreciated.

diogenesNY

 

[Onslaught]

By most models, the speed of light is the escape velocity of this universe. That is obviously impossible to achieve. It is unclear if the universe is finite. I tend to think it is from a strictly observational standpoint - e.g.. Olber's paradox. There may be 'stuff' outside our universe but I see no possible way to confirm this by observation,

I would be careful in saying that it is impossible to achieve faster than light travel, it may be highly improbable but not impossible. These are theories for a reason. If scientists have learned anything in our short time in this universe it is that "universal truth is not measured in mass appeal."

I agree that the universe will most likely turn out to be finite, but what if the speed of light can be reached or even surpassed, imagine the implications. Now I am admittedly slightly ignorant when it comes to these matters but my understanding of Einstein's famous equation E=mc^2 is that the amount of energy it takes to move an object is that objects mass multiplied by the speed of light squared. Hypothetically if we were able to control this much or MORE energy and focus it we should be able to travel light speed.

One problem I can't explain is that the faster you go or more energy you use your mass seems to increase a lot, which would require more energy to move but maybe when your mass reaches a certain amount you tear through the fabric of space-time.

Just a thought I had, feel free to mathematically, logically, or theoretically tear my argument to shreds. :-)

 

[map19]

E = mc^2 is nothing to do with moving mass. It is the energy equivalence of mass.
To move mass the simple F = ma is all that is needed.
As you go faster your mass does NOT increase. It's the problem posed by Special Relativity that a "Stationary" observer appears to see your mass increase. Or putting it another way, if you are moving compared with another frame of reference, observers on that frame see your mass as increased, while you see their masses as increased.
In your own frame, and their own frame, there is no increase.

 

[Onslaught]

Thanks for the clarification, I guess that idea is DOA.

Is there any reason to believe that F=ma doesn't work or works differently towards the 'edge' of the Universe or do we assume that since it works here it must work everywhere?