Where is the centre of the universe? Options

[Hey Hey]

Where is the centre of the universe?

Inflation theory implies expansion, but from where?

[lucid_dream]

if you're a 2D being on the surface of an expanding balloon, does it make sense to ask 'where'?

[Hey Hey]

if you're a 2D being on the surface of an expanding balloon, does it make sense to ask 'where'?

But surely that is a bad analogy as there is more to the universe than a surface. Doesn't it posses three-dimensionality? And, the big bang must have occurred at a location in the system that became spacetime.

[lucid_dream]

i was thinking it was like a 3D space expanding on the 'surface' of a 4D spacetime. I could be wrong though.

[Rick]

Actually, the center of the universe is on Earth. It's located at the center of your skull.

[Hey Hey]

Actually, the center of the universe is on Earth. It's located at the center of your skull.

http://www.universalleonardo.org/trail.php...il=345&work=330

[Lindsay]

HH, I AGREE with you!!!
Do you recall the speech from Thornton Wilder's play, Our Town, when one of the young characters of the play give her address?

She concludes with the words that Grover's Corners is, "...in the mind of God." IMHO, we are in it--the mind of GOD.

Amazing. What a pirivilege! What an opportunity!

[Rick]

... the big bang must have occurred at a location in the system that became spacetime.

The big bang is the system that became spacetime. Before the big bang, there was no space to be in the "center" of. One can never get outside the universe, so there is no way to see the big bang from outside.

So all points are equally in the center of the universe (if you must have one). I find it convenient to regard each person as the center, because that's where her or his viewpoint is.

But your intuition about the impossiblity of gravitational collapse may be correct. If every point is the "center" then every particle attracts every other gravitationally, yet is itself attracted. Imagine an infinite line through the center of your head. There is as much mass on one side of the line as there is on another (in an isotropic universe). Those gravitational forces attracting you toward the rest of the universe are exactly ballanced, so the net result is you are not being attracted anywhere, so no collapse is possible.

[Lindsay]

Rick writes,

"One can never get outside the universe, so there is no way to see the big bang from outside.

So all points are equally in the center of the universe (if you must have one).

I find it convenient to regard each person as the center, because that's where her or his viewpoint is."

Again, I agree. Theologically speaking, this is very panentheistic.

[Rick]

It's also consistent with atheism.

[Lindsay]

Atheism? Like, theism, it is such a broad term, don't you agree? But, IMO, atheism--certainly not negative atheism--and panentheism are not one and the same, ever.

Please, in keeping with the kind of precise mind I perceive you to have, may I ask you to be more precise. What kind of atheism do you have in mind?

BTW, Rick, if my memory serves me, I understand that you are not a confirmed atheist, yet.

Does my memory serve me, correctly? If so, what kind of a non-atheist are you?

[Lindsay]

HH, in the light of your signature, I thought you would enjoy this quote:

Blessed are they who have nothing to say and who cannot be persuaded to say it.
James Russell Lowell

[Hey Hey]

... the big bang must have occurred at a location in the system that became spacetime.

The big bang is the system that became spacetime. Before the big bang, there was no space to be in the "center" of. One can never get outside the universe, so there is no way to see the big bang from outside.

But when the big bang happened, there was created the spacetime. And when that happened, (or maybe a billionth of a second after) matter had location. Expansion continued and still is.

So all points are equally in the center of the universe (if you must have one). I find it convenient to regard each person as the center, because that's where her or his viewpoint is.

I don't understand how this can be when I can clearly see non-uniformity in the sky and in Hubble pictures of galaxies. Is there really evidence to suggest that the universe is symmetrical? I.e. do we know enough about the whole universe to say that Milne's cosmological principle is correct?

[Hey Hey]

WRT the balloon, I realize that the analogy of Eddington relates to a 2D structure attempting to describe the 3D universe, and the centre is not on the surface (=universe). But this all goes to show how a better analogy is needed - this one suits some purposes but not others.

[Hey Hey]

OK, I also understand that the explosion was of space, not an explosion in space.

[Rick]

... Is there really evidence to suggest that the universe is symmetrical? I.e. do we know enough about the whole universe to say that Milne's cosmological principle is correct?

Yes, there is evidence of symmetry on a large scale. Milne's cosmology may be correct.

http://world.std.com/~mmcirvin/milne.html

[Rick]

Atheism? Like, theism, it is such a broad term, don't you agree? But, IMO, atheism--certainly not negative atheism--and panentheism are not one and the same, ever.

If they are not the same, what quality of a pantheistic universe may observe to confirm it?

If there is no evidence of pantheism, them atheism is the preferred model because it's simpler.

http://www.houghtonmifflinbooks.com/catalo...leNumber=689776

"The God Delusion makes a compelling case that belief in God is not just wrong but potentially deadly. It also offers exhilarating insight into the advantages of atheism to the individual and society, not the least of which is a clearer, truer appreciation of the universe's wonders than any faith could ever muster."

[Hey Hey]

Question:

If the universe is infinite, then how can it be expanding, or wouldn't that mean it is getting bigger? Bigger than infinity?

[Rick]

Take a sheet of paper. The paper's surface contains an infinite number of points. Draw a circular boundary on the paper. The interior of that circle also contains an infinite number of points, even though it's a smaller area than the paper. Between any two points on the number line, there infinitely many other points. Infinity is big enough to expand.

[Hey Hey]

Take a sheet of paper. The paper's surface contains an infinite number of points. Draw a circular boundary on the paper. The interior of that circle also contains an infinite number of points, even though it's a smaller area than the paper. Between any two points on the number line, there infinitely many other points. Infinity is big enough to expand.

But the universe has no boundary (many think) and thus one could say we are dealing with just one set of infinite points. Also, if we can always divide part of an item that was deemed to be infinite into infinite fractions, then how could anything ever be infinite as everything smaller or bigger would also be infinite? Just a small point (!), but what about the universe is thought to be infinite (i.e. what property/ies)?

[Rick]

... but what about the universe is thought to be infinite (i.e. what property/ies)?

What makes the infinite universe theories interesting is that they propose that the universe is of infinite mass-energy. The conventional big-bang theory posits finite mass-energy (so the question before was "is it massive enough to re-collapse?").

Now that the accelerated expansion of space has been discovered, infinite mass theories have corroboration (so are getting more attention). That is, the infinite theories suggest that as the universe is uniform in density (overall) then every point is gravitationally pulled isotropically so collapse isn't possible, no matter how dense it is or how much mass it has.

So to answer the question directly, my favorite infinite universe theory (originated by my younger brother 25 years ago) says that the universe is of both infinite volume and infinite mass-energy. But even in an infinite universe that will eventually have an infinite number of civilizations, one of those civilizations (ours) had to arise first. This explains the Fermi paradox.

The pure mathematics of infinity and continuum isn't particularly relevant to physical thory, so counting infinite points between finitely spaced points is about as productive as counting fairies on a pinhead.

[simon]

is there an approximate location of the big bang ?

[Hey Hey]

counting fairies on a pinhead.

You do or do not believe in fairies then? Or is it counting you have issue with?

[Rick]

I never count numbers larger than a thousand. Do you mean magical fairies or the other kind?

[Rick]

is there an approximate location of the big bang ?

Yes, it's everywhere. Every point in the space of the universe was inside the big bang singularity.

[Lindsay]

WITH THE RECENT DEATH OF ROBERT JASTROW IN MIND
I bring this forward.
===================================================

is there an approximate location of the big bang ?

Yes, it's everywhere. Every point in the space of the universe was inside the big bang singularity.

Interestingly, the theologian, St. Augustine, way back in the fourth Century, said: God is like a circle whose centre is everywhere and whose circumference is nowhere."

No wonder the late (Feb.8) Robert Jastrow, the agnostic cosmologist said:
Quotes "For the scientist who has lived by his faith in the power of reason, the story ends like a bad dream. He has scaled the mountain of ignorance; he is about to conquer the highest peak; as he pulls himself over the final rock, he is greeted by a band of theologians who have been sitting there for centuries."

"There is a strange ring of feeling and emotion in these reactions [of scientists to evidence that the universe had a sudden beginning]. They come from the heart whereas you would expect the judgements to come from the brain. Why? I think part of the answer is that scientists cannot bear the thought of a natural phenomenon which cannot be explained, even with unlimited time and money. There is a kind of religion in science, it is the religion of a person who believes there is order and harmony in the universe, and every effect must have its cause, there is no first cause...

This religious faith of the scientist is violated by the discovery that the world had a beginning under conditions in which the known laws of physics are not valid, and as a product of forces or circumstances we cannot discover. When that happens, the scientist has lost control...

Consider the enormity of the problem. Science has proven that the universe exploded into being at a certain moment. It asks, what cause produced the effect? Who or what put the matter and energy in the universe? Was the universe created out of nothing, or was it gathered together out of pre existing materials? And science cannot answer these questions".

ABOUT AUGUSTINE:
=================
http://en.wikipedia.org/wiki/Augustine_of_Hippo
=====================================
Jan 17, 2007, 12:00 PM
Post #5

Rick, you wrote: "Actually, the center of the universe is on Earth. It's located at the center of your skull." Seriously said, or not, I like the point made. Very unitheistic--GOD as being around, in and through all things. The at-one-ment. Theologians speak of the doctrine of atonement.

[trojan_libido]

I also agree with Ricks explanation, because quite frankly its the only one that matters. Your Universe is as large as you've seen, heard, explored and imagined. All of those things are perceptions which are subjective to your experience.

Scientifically I think the centre of the current expanding Universe physical location is known. Spiritually its at the centre of your mind.

[Rick]

Thanks, guys. It's nice to be recognized (and I was serious). Wherever you go, there you are.

People sometimes like to run a thought experiment in which time runs backward, and we imagine the universe shrinking to the point from which it came. However, that way of looking at it is not correct, as there is no way to get outside the universe, so there is no way to see the universe shrink to a point. Any such vantage point would have to be outside the universe, so would not exist.

A better way to imagine it is to visualize being inside the universe and have all the matter come rushing at you as it shrinks to a point. Every person, even those in other galaxies would experience the same view in that thought experiment.

[maximus242]

I think perhaps one has to first ask the very old question "If the universe is expanding, what is it expanding into?"

Are we expanding into ourself? Of course technically this could be perceived as impossible, lets think of it like this.

If you put dough into a plastic bag and allow the dough to expand, it fills up more and more of the plastic bag.

Perhaps the universe works in a similar manner. If we look at the big bang as highly compressed matter, then rapid expansion, perhaps the universe expands into some sort of quantum dimensional structure much like how dough expands into a bag.

Another important question is, what is at the edge of the universe?

People thought the earth was flat, are we guilty of the same thing in thinking that at the edge of the universe there might be nothing just as how early explorers believed at the edge of earth you fall off?

"Those who do not learn from history are doomed to repeat it"

[trojan_libido]

What about another way to look at it. What if we're not expanding into anything. What if all matter is actually shrinking and displacing so it looks like expansion?