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Old Sep 16th 2013, 03:20 PM   #1
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Thinking outside the box

Is their any history of mind experiments taking the perspective of an observer outside of space/time?

Who, when and a reference would be awesome... thx!
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Old Sep 16th 2013, 06:15 PM   #2
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Originally Posted by Troll View Post
Is their any history of mind experiments taking the perspective of an observer outside of space/time?

Who, when and a reference would be awesome... thx!
This depends entirely on what you define as "outside."

Many Physicists talk about "domains" of universes where the Universe is composed of "bubbles" of space-time distributed in a meta-space of 6 dimensions. This is described by the term "pocket universes." These pockets have no contact with other pockets so they cannot be directly observed.

Another conceptualization of "outside" is given by M-theory, where there are "stacks" of "branes.". (The terms comes from the shortening of the word "membranes.") These branes do not touch so again they cannot be observed, either.

The last possibility is that there is no way to be an observer outside space-time. Conceptually our brains are not equipped to process the concept of "nothing." But that might be what lies "outside" the Universe. Mentally all of us, I suspect, think of the Universe to be sitting inside some kind of black higher dimensional space. But as far as I'm aware there is no reason (other than Mathematical) for the Universe to be sitting in any sort of hyperspace. And we wouldn't be able to detect it if it was.

Finally, as I mentioned in your other thread, the Universe can be modeled using General Relativity. The space-time path of our Universe is simply a graph. There is no reason for an outside observer.

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Old Sep 16th 2013, 06:54 PM   #3
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Thanks, I was speaking of a mind experiment. Why should the universe have a beginning just because we can't conceive of infinity?

I have learned to ignore that gnawing question... "Why is there anything?" and I think I will stick to simpler concepts like time with no beginning and no end.

Hey, if you were an observer outside of time/space you could see all of time and space!

Last edited by Troll; Sep 16th 2013 at 07:12 PM.
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Old Sep 17th 2013, 04:42 AM   #4
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The concept of our universe having existed for an infinite amount of time was the dominant thinking back in the 1800's and perhaps up to the 1930's. Part of this static universe theory also included the concept of an infinitely large universe, with an essentially homogeneous distribution of galaxies and stars within it. But then Hubble did his observations that show an expanding universe, and once you accept that data it's not too much of a leap to realize that at one point there must have been a start to the universe as we know it today. That does not mean that this is the first and only universe to have ever existed - perhaps everything goes through a never-ending repeating cycle of expansion followed by contraction. So an infinitely old series of universes is not necessarily wrong, but as Topsquark said there is no way of knowing for sure because the evidence for this can never be observed.
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Old Sep 17th 2013, 05:05 AM   #5
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Why? Because!

My answer to why the universe exists is "because it can"!

If one postulates an infinitely large probability space
and then suggest that anything that can exist, will exist,
Then the universe obviously can exist because it does.

There may however be other universes than can exist,
with suitable mutually consistent and stable set of "rules"
There will also be "universes" that can't exist...
where the "rules" do not form a stable, mutually consistent, set.

If one accepts this argument, then an internal observer can perhaps formulate an external perspective via imagination.
If one can define what criteria are necessary for something to be possible, and therefore to exist "somewhere" within probability space,
as opposed to things which are impossible, and therefore will not exist.

Note that while the list of posibilities might be infinite, the selection of those posibilities that form stable universes might be finite.

Last edited by MBW; Sep 17th 2013 at 10:09 AM. Reason: after thought
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Old Sep 17th 2013, 07:37 AM   #6
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Originally Posted by Troll View Post
Why should the universe have a beginning just because we can't conceive of infinity?
To supplement ChipB's comment about the beginning of the Universe, I agree that infinity doesn't come into play in regard to the beginning of the Universe. You might want to read this: Obler's Paradox. It's a simple argument that the Universe had to have some beginning. So far as I know he's the first to postulate this beyond the philosophers.

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Old Sep 17th 2013, 08:54 AM   #7
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My understandingof Olber's Paradox is that it provides an argument against an infinitely old universe of infinite size with homogenous and static distribution of stars and galaxies. But it doesn't preclude an infinitely old expanding (non-static) universe, or an infinitely old universe without a homogenous distrubution of stars.
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Old Sep 17th 2013, 09:16 AM   #8
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Originally Posted by ChipB View Post
...But it doesn't preclude an infinitely old expanding (non-static) universe, or an infinitely old universe without a homogenous distrubution of stars.
You know I never thought of that. Hey, I'm a Quantum Physicist not an Astronomer, Jim.

Thanks for the catch.

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Old Sep 17th 2013, 10:15 AM   #9
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Just to be mischevious:

Surely the original observer outside space and time appears in the opening lines of the bible.
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Old Sep 18th 2013, 01:01 PM   #10
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Random Thoughts

I have been considering the "outside the universe" idea.
The simplest answer seems to be that there is no outside, and therefore the question is meaningless.
However there are various "multiverse" theories around that would therefore allow an alternative viewpoint.
And there is the theory of branes drifting in a multidimensional realm where contact between these branes creates universes.
(see also http://www.newscientist.com/article/...bly-birth.html )
One thing that all options that allow an outside to the universe seem to share is that they re-introduce infinity.
This solves one philosophical conundrum in that it removes the beginning and end issues.
But infinity brings it's own philosophical baggage.

Last edited by MBW; Sep 19th 2013 at 05:15 AM.
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