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Old 26-July-2003, 06:02 PM
Hadrian Hadrian is offline
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If anyone is able, could you please answer these questions.

What do astronomers know of the very center of the universe?

Being the point of the original Big Bang, does it appear to be empty?

Do they even know exactly where it is?

And if it appears that even now it is still spewing out masses of energy that continue filling the universe, after a big Big Bang that came and went some 13 billion years ago - what is happening.
Also, considering that all that was created in the Big Bang is now still actively expanding outward – then logically, there should be a big empty space somewhere around where it originally happened.

It is easy to accept the Big Bang Theory in this expanding universe, but surely the greatest evidence of such an happening should be at the very center of the remains of that explosion. So why do we see or seem to know so little about the center of our universe.

Or am I perhaps missing something.

Please feel free to enlighten me.

Many Thanks.
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Old 26-July-2003, 11:54 PM
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Hi Hadrian,

To the best of our current state of knowledge ... there is no centre of the universe. The big bang can't be thought of as a normal bomb exploding - starting somewhere and expanding out from that. The "explosion" we think of as the big bang isn't like a bomb at all .. rather an explosion of interest. An explosion OF space rather than IN it. If it were like an ordinary explosion then we should be able to look through a telescope and see the edge of the universe, but instead we look out and see back into the universe ... (see the argument about the use of language in another thread is VERY applicable here!!). Just because the universe is expanding doesn't mean it is expanding into something. Still, the universe is expanding (pretty much) uniformly and equally in every part. There is a common way to visualize this expansion without there being a universal centre.
If you take a balloon and draw a couple of points on it and then blow it up the points will, seemingly, all be moving away from each other. The three dimensional universe is to be compared with the two dimensional surface of the balloon (ie the centre of the balloon isn't part of the surface and isn't to be thought of aas the centre of the universe). This isn't to say that the universe is 2D - it;'s much more. unfortunately our brains are unable to fathom the others so lets not try. It's also important to remember that while the points on the balloon (the galaxies in thhe universe) expand the galaxies don't expand within themsleves due to them being bound by gravity.

I hope that helps. Or I might have just confused things a little more.
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Old 27-July-2003, 01:14 AM
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It might also help (or serve to further confuse) to remember that we can only observe the universe "inside-out," i.e., the sphere of quasars that appears to surround us at distances of billions of light years from us do not form a sphere billions of light years in radius. If one could "see" the "big bang" or the "center," that "point" would necessarily be visible to us as the inside surface of a sphere billions of light years from us. To "convert" the visible universe to the "real" universe, one must turn the observed universe "inside-out." ...... from the book The Contracting Universe by John Lancas published April, 2000.
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Old 27-July-2003, 03:40 AM
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What a fascinating question! And even more fascinating are the answers!

Am I right, therefore, in thinking that we stand on the surface of the balloon whereas the theoretical centre of the universe is in the cenre of the balloon? ie, if we're standing on the surface of the balloon, we can't actually see the centre because, well, the surface of the balloon is in the way?

Or am I just talking rubbish?? LOL :huh:

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Old 27-July-2003, 04:26 AM
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no no ... that's the problem with the balloon analogy. The centre of the balloon is not the center of the universe. The 2D surface of the balloon is the only part that corresponds to the analogy. The 2D surface of the baloon IS the 3D universe.
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Old 27-July-2003, 10:11 AM
Hadrian Hadrian is offline
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Thankyou everyone for the answers:

Yes, I have heard of the balloon theory, but I’m still confused. The main problem being that all our best observations do as you say, seem to come from the observable edges of our universe, and my kind of logic suggests that if you want to know what started the fire, examine the embers.

I will wait and see if there are a few more answers and try and get my head around this one.

Regards

Adrian
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Old 27-July-2003, 02:53 PM
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Well, I think there might be a centre. I heard about the baloon theory from this forum and I agree partially. If the Universe expands, uniform or not, then the real centre could move too leading to another centre and so on.
So there could be two disscusions about the centre of the Universe: one of the first centre and the other about the actual centre.
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Old 27-July-2003, 04:41 PM
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Hi all.
Still trying to get my head around this skin of the balloon theory, so I visited the HUBBLE Site and reviewed some of their findings. (Listed below) Anything in brackets are my questions, and believe me I have plenty of them.

(I have come across the term 2d space used to explain the present state of the universe – sometimes even referred to as flat space – or the probability that if we could travel straight enough for long enough, we would end up were we started off. But if this were so then how could so much matter occupy such an apparently unwinding universe?)

January 15, 1996
STScI-1996-01
Hubble's Deepest View of the Universe Unveils Bewildering Galaxies across Billions of Years
Representing a narrow "keyhole" view stretching to the visible horizon of the universe, the HDF image covers a speck of the sky only about the width of a dime located 75 feet away. Though the field is a very small sample of the heavens, it is considered representative of the typical distribution of galaxies in space because the universe, statistically, looks largely the same in all directions. Gazing into this small field, Hubble uncovered a bewildering assortment of at least 1,500 galaxies at various stages of evolution.

(In all directions – does this then include the center of the universe? If so, then perhaps this is more representative of some which is growing – not merely expanding.)

Harry Ferguson, one of the HDF team astronomers added: "One of the great legacies of the Hubble Telescope will be these deep images of the sky showing galaxies to the faintest possible limits with the greatest possible clarity from here out to the very horizon of the universe."

(This statement verifies that we, or the galaxy of which we are such a small part, is indeed far far away from the outer reaches of the galaxy. And that is the outer reaches of a galaxy as it was 11 to 12 billions of years ago. How much bigger is it now?)

Essentially a narrow, deep "core sample" of sky, the HDF is analogous to a geologic core sample of the Earth's crust. Just as a terrestrial core sample is a history of events which took place as Earth's surface evolved, the HDF image contains information about the universe at many different stages in time. Unlike a geologic sample though, it is not clear what galaxies are nearby and therefore old, and what fraction are very distant and therefore existed when the universe was newborn. "It's like looking down a long tube and seeing all the galaxies along that line of sight. They're all stacked up against one another in this picture and the challenge now is to disentangle them," said Mark Dickinson of the HDF team.

(Surely the tunnel analogy is the one thing most representative of Three Dimensional Space. To travel through our galaxy or even from our galaxy to the Andromeda Galaxy is to travel through Three Dimensional Space – therefore traveling to any destination in the universe would be the same.)

Follow-up observations will be conducted by a variety of ground and space-base telescopes at other wavelengths of the electromagnetic spectrum, from X-ray through radio. An infrared camera scheduled to be installed in Hubble during the 1997 Servicing Mission will likely image the field to search for even farther primeval galaxies, whose light has been shifted to the infrared region of the spectrum by the expansion of the universe.

(And lastly – what exactly is the universe expanding into – I have read that it is created time and space as it expands and that we may never know what lays beyond – mostly because of the vast distances involved. But whatever lays out there – cause and effect tells me our universe may just be one of many)

Damn, I’m getting an headache – I’m off to take some pills.
Perhaps if I sleep on it, it might seem a little more logical when I wake up. Some hope.
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Old 27-July-2003, 11:55 PM
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"In the beginning was Nothing. No space, no matter or energy. But according to the quantum principle, even Nothing was unstable. Nothing began to decay; i.e. it began to "boil," with billions of tiny bubbles forming and expanding rapidly. Each bubble became an expanding universe. "

Dr. Michio Kaku
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Old 28-July-2003, 12:10 AM
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ahh VARN! Good to see you've been reading the brilliant Kaku!
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Old 28-July-2003, 02:29 AM
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Okay... BUT how can "nothing" do "something" like decay and boil?? :unsure:

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Old 28-July-2003, 07:10 AM
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The balloon analogy is a good one because it implies that there is no actual centre in 4 dimensional space, which is clearly the case. The centre of space would also be the "centre of time". If you were to travel around the outside of the balloon (theoretically), you could come around to the same point. But remember the surface of the balloon is 4-dimensional so you'd have to do some time travelling as well. Weird. Confusing...all of the above.

Kashi
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Old 28-July-2003, 12:02 PM
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A little history on the ballon analogy:

In the 1920s an astronomer named alexander freidmann gave two conditions for an expanding universe:

1) The universe is the same everywhere.
2) There is no point in the universe that can be said to be the centre of the expansion of the universe.

Visualise the univesre as a 3-d expanding balloon and ourselves as 2-d. so, we are on the 2-d surface, and cant see into the 3-d space of the balloon. But there is no point on our 2-d surface tat can be said to be the centre of the expansion (the expansion starts in 3-d space). Now ,put this analogy in our universe, with us as 3-d and the universe as 4-d (with time as the fourth dimension). The expansion is ba ck in time in the 4th dimension (into which we can't see).
I hope that explains it.
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Old 29-July-2003, 11:52 AM
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Dr. Kaku has made the assumption: 'at the beginning was
Nothing'. This cannot be proven and is a big assumption.
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Old 29-July-2003, 02:06 PM
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[b] according the the known facts the sun is in the centre of the solar system we know this because of the fact all the planets revolve around it and we have over whelming evidence to prove this.We also have overwhelming evidence to prove we have a centre in our milky way galaxy.....why is it so hard to find the centre of the universe?THE SAME ANALOGY CAN BE USED TO FIND THE CENTRE OF THE UNIVERSE BY USING THE COLOUR SHIFTS OF THE GALAXIES TO SEE THE DIRECTION OF THERE MOVEMENT AND MAP OUT WHETHER THERE IS A "CENTRE OF GRAVITY' WHERE ALL KNOWN CELESTIAL OBJECTS REVOLVE AROUND. Its most likely there are multiple universes within the existing one in a much larger universe ,otherwise it would be impossible for it to hold together. Similar to your ballon theory murmured in some opinions, however imagine a clown holding a whole bunch of little helium ballons at a street corner and each ballon is a little universe and the whole bunch would consist of the whole universe. these little ballons would be most likely be interconnected by "black holes" or "worm holes" to even the "pressure between the universes to keep them "constant" similar to tornadoes that balances out differential atmospheric forces. Which ballon would be the centre of the universe, the answer would be they would all have a centre of their own universes>
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Old 30-July-2003, 12:51 AM
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The background radiation from the big bang is the same measured from anywhere on earth if there was a center it would be more intense on one side.
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Old 02-August-2003, 01:08 AM
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Not true.
Remember that our perspective (in the middle) is an illusion.
See "The Contracting Universe" chapter on Topology of the Universe.
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Old 26-August-2003, 09:09 PM
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My EX thought that she was the center of the Universe. Was she ever wrong.

Wendell
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Old 31-August-2003, 09:47 PM
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This is the point at which science and religion merge. Neither is able to come up with a good explanation about why there is something rather than nothing. They both have devised hundreds (if not thousands)of theories, but neither has any substantial proof of their theories.

From the viewpoint of science, the big bang created space. This wasn’t an explosion that expanded into space; there was no space before the big bang. That’s hard to understand, but so is a God that has always existed. God created the universe out of nothing, and the big bang created the universe out of nothing. Same-o, same-o!

If there is a center to the universe we can’t ever find it because we can’t see any of the current universe: only the universe in the past. We use the concept of a universe without a center as almost an act of faith. We can not prove that the universe has no center. There is nothing to establish the lack of center in an empirical manner.

Of course it is confusing, no one in the history of humanity has understood it. So, don’t fee bad because you don’t.

Bud
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Old 01-September-2003, 02:51 AM
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What we are looking at here, is a physical interpretation of something which is multi-dimesional.

Who can say where is the physical center of the Universe?
And if so, by what criteria. Does one consider the space of physical center? or the center of the distribution of matter? And then again, what qualifies? Is dark matter included? or elements from other possible dimensions? And to what extent? Then the element of time. At what point of time do we want to consider?

It is becoming very interesting to consider what may have been before the big bang. Or even how it came about. Here's a hypological perspective.

What if this life form often called 'God', and sometimes dubbed a Supreame being,
is from another dimension? One that perhaps exists above and beyond our physical realm. One which we can not detect by means available to us.
And perhaps this above and beyond realm pre-existed ours by enough time for such life form(s) to develop.

Could such a being have introduced elements from his realm to create a new realm which had not existed before? Such an event may have had a violent reaction. Perhaps even a big bang.

Some long amount of time later life develops, us.
If we are part of a realm which is infearier to the realm from which it origionally came, how can we see back past our own beginning?

How can we concieve something existing and/or pre-existing us which we can not detect with our senses?
How do we contact beings from such a realm? Or do they contact us?
And if so, what criteria is set for a relationship between us and them?

Hypological of coarse.
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Old 02-September-2003, 03:42 PM
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The present day understanding of the center of the universe is the result of the observed expansion of galaxies. Generally, the further away a galaxy is, the faster it is moving away. Every observer in every galaxy would perceive that his or her galaxy is at the center of an expanding universe. This observation is also responsible for the “big bang” model, which describes the beginning of the universe; run the clock of time in reverse and all the galaxies move back together.

The presently accepted model stops this expansion at the boundary of galaxies. Gravity is supposed to keep galaxies together, resisting the expansion of space. The balloon model referred by others previously has the galaxies represented by fixed pennies or buttons. Another example often given in college texts about the expansion, is the rising raisin bread model, with raisins representing galaxies that are being spread further apart due to the expansion of the expanding bread dough.

I have another model describing the expansion that allows galaxies and matter itself to expand. (According to the proposed theory this is a very slow expansion, 12 billion years to double in size at the current rate of expansion). Celestial and atomic stability is also preserved. The novel part of this model is that not only are galaxies the perceived center of the universe, any and every location becomes the perceived center of an expanding universe.

Was church dogma right all along?

snowflake
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Old 02-September-2003, 09:19 PM
Tripoli-Kid Tripoli-Kid is offline
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Where is Earth in relation to the center of the universe <_<
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