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flat universe question

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olympus mon

olympus mon

Esteemed member
OG Pioneer
so the universe was shown to be flat by recent studies. my brain is having a hard time comprehending this. can anyone explain it or is it all mathematics and not able to be described and visualized?

also the WMAP, how is that image a pic of the early universe?
 
Not entirely sure if I am correct, and anyone who knows better please correct me...

But if the universe is flat, imagine that all the matter exists as if we are on the surface of an inflating baloon...all that matter exists along the thickness of the material and is ever expanding outward along that "flat" surface.
 
ok... but thats a 2 dimensional description. the skin of the balloon . what if i point my space ship up or down not just along the the outer surface.
or am i misunderstanding your analogy?

how could the universe be flat if you can travel in three directions?
 
olympus mon said:
ok... but thats a 2 dimensional description. the skin of the balloon . what if i point my space ship up or down not just along the the outer surface.
or am i misunderstanding your analogy?

how could the universe be flat if you can travel in three directions?
Click to expand...

The surface area of a baloon is three dimensional...just very "thin" along the "Z" axis...so it is not a 2 dimensional explanation.
 
Pokey said:
Who said the universe is flat?

Pokey
Click to expand...

i saw it on the "through the wormhole" series on the science channel last week. i think it was in the episode covering black holes. awesome documentary btw. however they talked about the experiment that showed this to be true but never explained how the universe could be flat.
 
From what I understand, the balloon analogy is just a model to help humans with a 3d orientated brain to understand it better. It probably doesn't actually look like a balloon shape object to the external observer.

Space as most of us commonly think of it is 3 dimensional. In order to explain wormholes and gravity, it's easier to think of it as a balloon so we can visualise a wormhole come from one point on the balloon, through the hollow centre of the balloon to the other side creating a shortcut.

Also when explaining gravity, it is easy to visualise heavier objects on the surface of the balloon creating a larger dent than less massive objects, thereby pulling nearby objects towards it.

So as the balloon expands, it's surface area increases and so the universe expands and becomes less dense.

As for the big crunch, what if the balloon pops? lol
 
I think its more like a hologram. All the information for a fully three dimensional object is encoded on a two dimensional plane. So the volume of the sphere is an illusion created by the info on the skin.

..or something like that, I think.
 
MySmelf said:
I think its more like a hologram. All the information for a fully three dimensional object is encoded on a two dimensional plane. So the volume of the sphere is an illusion created by the info on the skin.

..or something like that, I think.
Click to expand...
ok im kind of hearing you. is this just an idea of yours or is this what you think the science is showing?
 
olympus mon said:
i saw it on the "through the wormhole" series on the science channel last week.
Click to expand...

Olympus man, have u seen ''what the hell do we know about rabbit hole''

from viewing your discussion i think you would enjoy the doc! very in depth through and bit hard to understand @ times (all quantum mechanics & physics, lol)

Its on torrentz.com (but i can uplaod for you if u ever wanna see it and dont wanna dl torrents)
 
I don't know about the evidence that the universe is "flat", but I'm pretty sure when they talk about a flat universe, it's with respect to a four-dimensional perspective.

Think of a gigantic sheet of paper, millions of lightyears wide; it's got plenty of length and width, but from a three-dimensional perspective it has essentially no height. Our universe could be shaped analagously; it stretches billions of lightyears in all directions; it has length, width, and height... but from a four-dimensional perspective, it could be as flat as a sheet of paper is from our three-dimensional perspective.
 
Check these links:

* Entropic gravity - Wikipedia
This theory tries to explain gravity with the correlation between entropy and gravity (I like this one!). I mention this one since it can connect with the Causal dynamical triangulation which I will link later in this post (and of course since Entropymancer made a post in this thread :D).

* Holographic principle - Wikipedia
General Holographic principle information


Then to the major kicker:
* Causal dynamical triangulation - Wikipedia
Theory about how spacetime fabric evolves.

Check these two quotes:
Causal dynamical triangulation said:
It is widely accepted that, at the very smallest scales, space is not static but is instead dynamically-varying. Near the Planck scale, the structure of spacetime itself is constantly changing, due to quantum fluctuations. This theory uses a triangulation process which is dynamically-varying and follows deterministic rules, or is dynamical, to map out how this can evolve into dimensional spaces similar to that of our universe
Click to expand...

Causal dynamical triangulation said:
A simplex is the generalized form of a triangle, in various dimensions. A 3-simplex is usually called a tetrahedron, and the 4-simplex, which is the basic building block in this theory, is also known as the pentatope, or pentachoron. Each simplex is geometrically flat, but simplices can be "glued" together in a variety of ways to create curved spacetimes. Where previous attempts at triangulation of quantum spaces have produced jumbled universes with far too many dimensions, or minimal universes with too few, CDT avoids this problem by allowing only those configurations where cause precedes any event. In other words, the timelines of all joined edges of simplices must agree.
Click to expand...

Good reading food. Happy knowledge hunting!


Kind regards,

The Traveler
 
olympus mon said:
MySmelf said:
I think its more like a hologram. All the information for a fully three dimensional object is encoded on a two dimensional plane. So the volume of the sphere is an illusion created by the info on the skin.

..or something like that, I think.
Click to expand...
ok im kind of hearing you. is this just an idea of yours or is this what you think the science is showing?
Click to expand...

No, not my idea. Check out The Traveler's link on the Holographic principle.
 
I've just come across a reference to the flatness of our universe in the book I'm reading! Funny coincidence, eh? The book (In search of the Multiverse by John Gribbin) makes the distinction between flat and curved universes.

Curved as in if you traveled far enough in the same direction, you would arrive back at the spot you started (it would take quite a while....). The book states with a reassuring amount of certainty that our universe is not curved in that manner, so it is considered flat. That's not what I was imagining when I read the title of this thread (think flat like a pancake), so I'm happy to not be confined to a really flat universe.

I'm too busy too make the 14 billion plus light year journey across the universe to test John Gribben's math, but I believe him anyway.


Pokey the Relieved
 
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