a flat universe?

[syntax252]

When I say nanoseconds, I pretty much meant that 90% of its size was created almost instantly.

 

Why did it's rate of expansion change so radically?

 

There is nothing in the center to pull back on the galaxies and there is no atmosphers to retard it's expansion, so what force acted on these objects to change the rate of expansion?

[[Tycho?]]

When I say nanoseconds' date=' I pretty much meant that 90% of its size was created almost instantly. The soap bubble I mentioned, has to be viewed as a spherical shape without a center. The universe is expanding into nothing, but its only the sphere's edges that are moving outward. There is nothing inside of the sphere.

 

Forget the Christmas ornament....I like the soap bubble better.

 

Imagine the soap bubble the size of a basketball floating still in the air. Now imagine that it was nighttime, and the soapy solution forming this bubble was a faint glowing neon blue. A faint neon sphere.

 

If you could walk up to this bubble without breaking it, walk around it and look closely, you would see many swirls and designs on the outside of this sphere which would represent our galaxies. Yet nothing but blackness would be inside and outside of the bubble. This black represents the nothing that our universe came from.

 

If you walked up to it and looked even closer, you would see that between these many swirls and designs around the circumference there would be plain areas with no swirls. Since these areas of the bubble are thinner than the parts making up the swirls, it is much lighter and fainter. To me this would represent the dark matter that we cannot see. This dark matter is also expanding.

 

If you could add an air source and begin adding air to the inside of the bubble, it would grow larger, but the center nothing would get larger too. The event horizon or outside edge of this bubble would move outwards and the swirls would move farther away from each other.

 

To get from one side of the bubble to the other, you would have to travel its circumference. You cannot go thru the center. Just place a magical car on the surface of the bubble and drive around the outside. Like you do on earth.

 

The pancake universe doesn't cut if for me. I just don't see a big bang creating something flat like that. And, I do believe the big bang had a center at one time with the bubble radiating outward at a pretty uniform rate.

 

I really look at all the links that you guys give me....thanks for that.

Again, I'm still learning, but its hard to find which is the best model to stick with.

 

Bettina[/quote']

 

I understand the analogy, but one question- for this example, how do you think of the universe as flat? The only surface is that of the sphere, which is obviously not flat. I can't think of a way that this analogy can be used to think of the over all curvature of the universe.

[syntax252]

I got the impression that she envisions a universe that is flat in perception, like the world is flat if one is only looking at a few sq. miles of it.

 

I gather that this "bubble" has a skin that is of considerable thickness, but when compared to the whole of the universe, is relitively thin.

 

Like our atmosphere compared to the whole world?

[[Tycho?]]

I got the impression that she envisions a universe that is flat in perception' date=' like the world is flat if one is only looking at a few sq. miles of it.

 

I gather that this "bubble" has a skin that is of considerable thickness, but when compared to the whole of the universe, is relitively thin.

 

Like our atmosphere compared to the whole world? [/quote']

 

The bubble wouldn't have a thickness, only a surface area.

 

And in perception isn't what I'm looking for here. In our perception the universe is quite curved since we are in a gravity well at the moment. We are talking about the overall curvature, which is either flat or very close to flat.

[syntax252]

'']The bubble wouldn't have a thickness, only a surface area.

 

How do you know that? It's her bubble, not yours.

 

 

And in perception isn't what I'm looking for here. In our perception the universe is quite curved since we are in a gravity well at the moment. We are talking about the overall curvature, which is either flat or very close to flat.

 

Well when you have a sphere as large as the universe, any part of it is pretty near to flat.

[Sayonara]

hey..im currently working on a big research papaer talking bout the shape of the universe..i jus started and im alreayd confused..it seems that ther are three posibilities for the shape and that the universe is flat.what does this mean? flat would mean having a single flat plane..but how is that possible when space time actually curves..i mean isnt the universe have depth to it? how can it simply be flat..please help!

Probably not what you are after, but you may find these interesting (and may even be expected to come across them in your research):

 

http://www.amazon.com/exec/obidos/ASIN/014043531X/104-6628655-4226314

[Bettina]

Thanks for the book link.

I bought Flatland, Sphereland, Spaceland, and Geometry.

(Actually it was dads credit card)

 

I still have a hard time with the flat universe concept even though WMAP is now leaning toward it. Geez, it was only a year and a half ago that the sphere was still valid. I'm going to learn more about this.

 

Bettina

[Stumblebum]

The no boundary finite universe analogy works for me. If as it has been suggested the universe rides a membrane that surrounds nothingness and is expanding likewise into the same then it surely is a colossal sphere. Perhaps so big that it appears flat.

 

I can't recall the name of the experiment but didn't someone send up a device designed to measure the geometry of the universe and the result was the universe is flat with slight curvature? Seeing how mass affects the fabric of spacetime would not any device so designed flatten spacetime just by its mere presence?

 

Why does the universe appear the same from wherever one observes it? Where else but on the surface of a sphere would the horizon always be the same distance away from you from any point.

 

Because I am no cosmologist I've probably missed a basic principle somewhere that says I'm out to lunch on this one. Dimensions are difficult to grasp at times but at the same time we exist on this 3D + 1 plane and will have to provide the answers from this vantage point. Are the answers there?

[Jacques]

I like the bubble analogy but more the bubbles in bathtub. The Sloan survey show at large scale a bubble structure big void surronded by galaxies cluster. Other evidence show the web structure. The difference with the analogy is that galaxies occupy a volume, have a thickness occupy 3D or four. I will stop to three.

I had a thought about these void that not finally that void. The distant supernovae survey (don't remember the name) showed that the expansion is accelerating. Dark energy was born!

Ok my thought: black hole feeding the voids with dark energy or more simply energy causing the acceleration of the expansion. Withe hole a la sauce.

[Spyman]

yes i know flat means flat sheet of paper and yes i know flat means parallel lines cant meet and sum of triangles are 180 degrees..but which "plane" is it that is exactly flat, when you have such a deep universe?? like if you say the earth is flat, you're referring to the surface on which we live..but for the universe, where is that????????

I think with flat they mean that all the planes are flat - all three dimensions !

Otherwise they could be bent someway in another dimension yet unknown.

 

Imagine space as a box - if bent in a another dimension, which we can't detect, then Two sides of the box could touch eatch other, even opposites.

Now place Two objects in the box - gravity should pull them togheter - but if they are much separated, close to the sides that touch, (or are close to eatch other), then gravity could pull them to those sides, (if working through this dimension), thus for us faking a repelling force stronger than gravity.

 

Depending how the universe is bent, (like the box), it will end in different ways, (if gravity works outside our three normal dimensions).

 

In other words if space is flat then a box is a box with flat surfaces,

- if not the box could be twisted in many ways and shapes, but we still only see it as a box.

[Stumblebum]

Why do cosmologists and theorists insist on a multi dimensional universe? Is it because they've run out of avenues to pursue in this 3D universe? Is this the only way to go, imagine this, imagine that?

 

Perhaps a whole new way of thinking is required or is it impossible to come up with a TOE without extra dimensions. From my side of the fence it seems like a lot of head scratching going on with the cosmology side. I'm not pretending to know the answer, just wondering.

[Bettina]

Why do cosmologists and theorists insist on a multi dimensional universe? Is it because they've run out of avenues to pursue in this 3D universe? Is this the only way to go' date=' imagine this, imagine that?

 

Perhaps a whole new way of thinking is required or is it impossible to come up with a TOE without extra dimensions. From my side of the fence it seems like a lot of head scratching going on with the cosmology side. I'm not pretending to know the answer, just wondering.[/quote']

 

Thats what I think too. When they had no answers to some questions, they thought up quantum mechanics.

I dont believe in the string theory stuff, parallel universes, and other dimensions. I only believe what those telescope show me. Your not alone in your thinking....and no...my mind is not closed.

 

Bettina

[KholdStunner]

The density of the Universe determines its geometry or shape. If the density of the Universe exceeds the so-called "critical density", then the shape of space is curved like the surface of a huge sphere. If the density of the Universe is less than the "critical density", then the shape of space is curved like the surface of a saddle. If the density of the Universe exactly equals the "critical density", then the shape of the Universe is flat like a sheet of paper.

[Stumblebum]

What if the entire universe is afloat? Are we to assume the universe, no matter what its geometry, is surrounded by nothingness?

[Cadmus]

Why do cosmologists and theorists insist on a multi dimensional universe? Is it because they've run out of avenues to pursue in this 3D universe? Is this the only way to go' date=' imagine this, imagine that?

 

Perhaps a whole new way of thinking is required or is it impossible to come up with a TOE without extra dimensions. From my side of the fence it seems like a lot of head scratching going on with the cosmology side. I'm not pretending to know the answer, just wondering.[/quote']Scientists believe that we live in a universe with 3D of space and 1D of time, because our language supports such an idea. However, our senses notwithstanding, it is quite apparent to many that this cannot be all that there is. Although scientists are currently struggling and confused as to how to understand greater dimensions, it is quite clear to many that they must be there. Without greater dimensions, there is just too much inconsistency and incompleteness in our physical model of nature.

[Jacques]

Here is a good article on the subject. It goes against the curved space of relativity. Does it make sense for you ?

Thanks

 

http://www.quackgrass.com/space.html

"Curved space" is a staple of 20th Century thought. Space warps are a cliche of science fiction. Generations of science students have tried to make sense of curved space, and succeeded only in warping their minds. Curved space is taken for granted among the learned; if you protest that curved space is absurd, they roll their eyes and shake their heads pityingly.

[J.C.MacSwell]

More

 

Curved space is simply a system of measurements made with squidgy units. (E.g., Jello measuring sticks.) That is the trivial secret behind the gaudy curtain of curved space theories. Despite the mighty theatrics, there is nothing behind the curtain but a dishonest little man who refuses to admit that he fudged the units.

 

I have not read and understood where he's coming from but that part cracked me up.

[syntax252]

I have been reading this thread and I am not sure I understand what you folks mean when you refer to "the universe."

 

Are you talking about all the matter that was created and blasted out into "space" at the moment of the "big bang?" The galaxies, stars, nebula and such?

 

Or are you talking about whatever there was out there before the BB?

[Bettina]

I hope this is right, if not, please correct my thinking.

 

When we speak of the Universe, we can speak two different ways.

 

1. The universe is the entire area that happened as the result of the big bang that we are capable of seeing.

 

2. The universe is the entire area that happened as the result of the big bang and includes what we see and what we are yet incapable of seeing but nevertheless must be there.

 

There is no universe outside of what the big bang created.

 

So if you draw a sphere (or flat piece of paper if your a flatlander) and say that is what the big bang created, then that is our universe.

 

Bettina

[Cadmus]

When we speak of the Universe' date=' we can speak two different ways.

 

1. The universe is the entire area that happened as the result of the big bang that we are capable of seeing.

 

2. The universe is the entire area that happened as the result of the big bang and includes what we see and what we are yet incapable of seeing but nevertheless must be there.[/quote']The first of these is very limited in value and usage.

 

There is no universe outside of what the big bang created.

This speculation on your part is poorly phrased, in my opinion. Scientists typically consider the universe only in terms of post big bang, as they have no methods currently to consider otherwise. However, this is not in itself proof, or even strong evidence, that that is all that there is.

[Bettina]

The first of these is very limited in value and usage.

 

 

This speculation on your part is poorly phrased' date=' in my opinion. Scientists typically consider the universe only in terms of post big bang, as they have no methods currently to consider otherwise. However, this is not in itself proof, or even strong evidence, that that is all that there is.[/quote']

 

If the books I'm reading are wrong or outdated, could you please tell me about some of the ones that make you think that? I'm not being sarcastic. I want to know what the latest works are.

 

Bettina

[Cadmus]

If the books I'm reading are wrong or outdated, could you please tell me about some of the ones that make you think that? I'm not being sarcastic. I want to know what the latest works are.

There are many good books out there. My point here refers to your interpretation. You suggest that there is no unverse outside of what the big bang created. I doubt that you found that in a book. Modern science concerns the universe post big bang. Modern science does not contend that there is nothing outside of the big bang, but only that it is currently outside the bounds of modern science. Many scientists have speculated on pre big bang. They have not been able to study it in a scientific manner, but that does not mean that they all deny that there is any existence outside of the big bang. Please reread what I wrote in post #45.

 

In response to your first statement, that the universe consists only of what we can see now: I doubt that you got that from a book either. I have never heard anyone suggest that if we cannot see it then it cannot exist.

 

Please continue to read books. Most likely you are reading good books. I am simply suggesting another way to interpret what you are reading.

[Bettina]

There are many good books out there. My point here refers to your interpretation. You suggest that there is no unverse outside of what the big bang created. I doubt that you found that in a book. Modern science concerns the universe post big bang. Modern science does not contend that there is nothing outside of the big bang' date=' but only that it is currently outside the bounds of modern science. Many scientists have speculated on pre big bang. They have not been able to study it in a scientific manner, but that does not mean that they all deny that there is any existence outside of the big bang. Please reread what I wrote in post #45.

 

In response to your first statement, that the universe consists only of what we can see now: I doubt that you got that from a book either. I have never heard anyone suggest that if we cannot see it then it cannot exist.

 

Please continue to read books. Most likely you are reading good books. I am simply suggesting another way to interpret what you are reading.[/quote']

 

Sorry to bring up an old thread, but It took awhile to find the books and pages that I got my information from and I have dozens of cosmology books. I just wanted to set the record straight that I don't just make things up. My post 44 is what I got out of books. I know you weren't mocking me, I just don't like to leave loose ends open.

 

The book I got the info from is called "The Matter Myth" by Paul Davies and John Gribbin. On the specific page 122 of that book, it states "The big bang was the abrupt creation of the Universe from literally nothing: no space, no time, no matter". To me this imples there was nothing before the big bang.

 

On specific page 120 of that book, it also states "Space itself, and time were created, like matter, in the big bang; there was no "outside" into which the explosion occurred." To me, it implies there is nothing more than what the big bang created.

 

Another thing the book mentions is that our universe could just "look" like its speeding up but in fact could be the slowing down from the initial expansion. As the expansion continues to slow, galaxies that are receding "faster than light" from our point of view, slow to a speed less than that of light. The effect of this is that the universal horizon appears to grow outward as time passes.

 

The horizon of the big bang is moving away from us faster than the speed of light. (faster than the universe) so that as time goes by it encompasses more and more galaxies, even though the galaxies continue to retreat from us.

 

On other pages it states that the universe is what we can see (light) and also includes what we can't see out to the inflation event horizon (what we can't see). There is nothing beyond that event horizon created by the big bang.

 

The book may be the interpretation of two people, but this is what I read from that book.

 

Bettina

[Martin]

 

...The book I got the info from is called "The Matter Myth" by Paul Davies and John Gribbin. On the specific page 122 of that book' date=' it states [i']"The big bang was the abrupt creation of the Universe from literally nothing: no space, no time, no matter".[/i] To me this imples there was nothing before the big bang...

 

I have no other book to suggest. Glad you decided to tie up loose ends by giving your page references and your sources! wish everybody would do that.

 

fine to bring back old threads. sometimes a lot more interesting than the latest new ones.

 

however "the matter myth" by Davies and Gribbin is dated 1992

 

much of what Davies Gribbin said is right, but some is ten years old.

to bring the picture a little up to date please have a look at

 

http://arxiv.org/abs/physics/0407071

this will give the abstract, you click on PDF to get the full article.

this is a short, easy to read (SciAm type) account by a German journalist

so there are no technical barriers. I have links to the journal articles it is

based on if you are curious about the details. However the journalist

is a Philosophy of Science expert in his own right. he is competent, as well as being a good popularizer.

I would like to know what you think of the article, if you take a look at it.

[us.2u]

I cannot imagine a flat universe' date=' nor can I imagine one like a Christmas ornament, (although that would be easier than flat)

 

I have always wondered why it all has to be [b']one[/b] big bang?

 

Look, we think we know that there are such things as black holes. And we think we know that there are many of them. Why couldn't it be the case that once a black hole becomes dense enough--once it has attracted enough matter into it--that it just explodes and creates a galaxy?

 

Does it have to be the whole damned universe at once?

 

Why not a black hole exploding somewhere in the universe every billion years or so? Let's call it the "popcorn theory" of galaxy creation.

I agree Syntax we're all ready to accept the big-bang & there were proberly lots of them