The shape of the universe and what is at it's edge. Turn your noggins on.
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10-01-2012, 02:34 PM
The shape of the universe and what is at it's edge. Turn your noggins on.
Okay, KC and I had this discussion a while back and you can imagine, it led to some pretty mindblowing discussion. I randomly wondered one day, what is the shape of the universe? So I Google'd it and Wikipedia being as reliable as ever popped up first. So here is the article written on Wiki.

http://en.wikipedia.org/wiki/Shape_of_the_Universe

Quote:The local geometry of the universe is determined by whether Omega is less than, equal to or greater than 1. From top to bottom: a spherical universe, a hyperbolic universe, and a flat universe.The shape of the universe is a matter of debate in physical cosmology over the local and global geometry of the universe which considers both curvature and topology, though, strictly speaking, it goes beyond both. In practice, more formally, the debate seeks a 3-manifold that corresponds to the spatial section (in comoving coordinates) of the 4-dimensional space-time of the universe.

The Wilkinson Microwave Anisotropy Probe (WMAP) has confirmed that the universe is flat with only a 0.5% margin of error.[1] Within the Friedmann-Lemaître-Robertson-Walker (FLRW) model, the presently most popular shape of the Universe found to fit observational data according to cosmologists is the infinite flat model,[2] while other FLRW models that fit the data include the Poincaré dodecahedral space[3][4] and the Picard horn.[5]

Consideration of the shape of the universe can be split into two; local geometry, which relates especially to the curvature of the universe, especially in the observable universe, and global geometry, which relates to the topology of the universe as a whole, measurement of which may not be within our ability. If the observable universe encompasses the entire universe, we may determine the global structure by observation. If the observable universe is smaller than the entire universe (in some models it is many orders of magnitude smaller or even infinitesimal), observation is limited to a part of the whole. Possibly the universe is small in some dimensions and not in others (like a cylinder). If a small closed loop, one would see multiple images of an object in the sky, although not necessarily of the same age.

Cosmologists normally work with a given space-like slice of spacetime called the comoving coordinates, the existence of a preferred set of which is possible and widely accepted in present-day physical cosmology. The section of spacetime that can be observed is the backward light cone (all points within the cosmic light horizon, given time to reach a given observer), while the related term Hubble volume can be used to describe either the past light cone or comoving space up to the surface of last scattering. To speak of "the shape of the universe (at a point in time)" is ontologically naive from the point of view of special relativity alone: due to the relativity of simultaneity we cannot speak of different points in space as being "at the same point in time" nor, therefore, of "the shape of the universe at a point in time".

Local geometry (spatial curvature)
The local geometry is the curvature describing any arbitrary point in the observable universe (averaged on a sufficiently large scale). Many astronomical observations, such as those from supernovae and the Cosmic Microwave Background (CMB) radiation, show the observable universe to be very close to homogeneous and isotropic and infer it to be accelerating.

FLRW model of the universe
In General Relativity, this is modelled by the Friedmann-Lemaître-Robertson-Walker (FLRW) model. This model, which can be represented by the Friedmann equations, provides a curvature (often referred to as geometry) of the universe based on the mathematics of fluid dynamics, i.e. it models the matter within the universe as a perfect fluid. Although stars and structures of mass can be introduced into an "almost FLRW" model, a strictly FLRW model is used to approximate the local geometry of the observable universe.

Another way of saying this is that if all forms of dark energy are ignored, then the curvature of the universe can be determined by measuring the average density of matter within it, assuming that all matter is evenly distributed (rather than the distortions caused by 'dense' objects such as galaxies).

This assumption is justified by the observations that, while the universe is "weakly" inhomogeneous and anisotropic (see the large-scale structure of the cosmos), it is on average homogeneous and isotropic.

The homogeneous and isotropic universe allows for a spatial geometry with a constant curvature. One aspect of local geometry to emerge from General Relativity and the FLRW model is that the density parameter, Omega (Ω), is related to the curvature of space. Omega is the average density of the universe divided by the critical energy density, i.e. that required for the universe to be flat (zero curvature).

The curvature of space is a mathematical description of whether or not the Pythagorean theorem is valid for spatial coordinates. In the latter case, it provides an alternative formula for expressing local relationships between distances:

If the curvature is zero, then Ω = 1, and the Pythagorean theorem is correct;
If Ω > 1, there is positive curvature; and
if Ω < 1 there is negative curvature.
In the last two cases, the Pythagorean theorem is invalid (but discrepancies are only detectable in triangles whose sides' lengths are of cosmological scale).

If you measure the circumferences of circles of steadily larger diameters and divide the former by the latter, all three geometries give the value π for small enough diameters but the ratio departs from π for larger diameters unless Ω = 1:

For Ω > 1 (the sphere, see diagram) the ratio falls below π: indeed, a great circle on a sphere has circumference only twice its diameter.
For Ω < 1 the ratio rises above π.
Astronomical measurements of both matter-energy density of the universe and spacetime intervals using supernova events constrain the spatial curvature to be very close to zero, although they do not constrain its sign. This means that although the local geometries of spacetime are generated by the theory of relativity based on spacetime intervals, we can approximate 3-space by the familiar Euclidean geometry.

Possible local geometries
There are three categories for the possible spatial geometries of constant curvature, depending on the sign of the curvature. If the curvature is exactly zero, then the local geometry is flat; if it is positive, then the local geometry is spherical, and if it is negative then the local geometry is hyperbolic.

The geometry of the universe is usually represented in the system of comoving coordinates, according to which the expansion of the universe can be ignored. Comoving coordinates form a single frame of reference according to which the universe has a static geometry of three spatial dimensions.

Under the assumption that the universe is homogeneous and isotropic, the curvature of the observable universe, or the local geometry, is described by one of the three "primitive" geometries (in mathematics these are called the model geometries):

3-dimensional Flat Euclidean geometry, generally notated as E3
3-dimensional spherical geometry with a small curvature, often notated as S3
3-dimensional hyperbolic geometry with a small curvature
Even if the universe is not exactly spatially flat, the spatial curvature is close enough to zero to place the radius at approximately the horizon of the observable universe or beyond.

Global geometry
Global geometry covers the geometry, in particular the topology, of the whole universe—both the observable universe and beyond. While the local geometry does not determine the global geometry completely, it does limit the possibilities, particularly a geometry of a constant curvature. For this discussion, the universe is taken to be a geodesic manifold, free of topological defects; relaxing either of these complicates the analysis considerably.

In general, local to global theorems in Riemannian geometry relate the local geometry to the global geometry. If the local geometry has constant curvature, the global geometry is very constrained, as described in Thurston geometries.

A global geometry is also called a topology, as a global geometry is a local geometry plus a topology, but this terminology is misleading because a topology does not give a global geometry: for instance, Euclidean 3-space and hyperbolic 3-space have the same topology but different global geometries.

Two strongly overlapping investigations within the study of global geometry are whether the universe:

Is infinite in extent or, more generally, is a compact space;
Has a simply or non-simply connected topology.
Detection
For a flat spatial geometry, the scale of any properties of the topology is arbitrary and may or may not be directly detectable. For spherical and hyperbolic spatial geometries, the curvature gives a scale (either by using the radius of curvature or its inverse), a fact noted by Carl Friedrich Gauss in an 1824 letter to Franz Taurinus.[6]

The probability of detection of the topology by direct observation depends on the spatial curvature: a small curvature of the local geometry, with a corresponding radius of curvature greater than the observable horizon, makes the topology difficult or impossible to detect if the curvature is hyperbolic. A spherical geometry with a small curvature (large radius of curvature) does not make detection difficult.

Analysis of data from WMAP implies that on the scale to the surface of last scattering, the density parameter of the Universe is within about 2% of the value representing spatial flatness.[7]

Compactness of the global shape
Formally, the question of whether the universe is infinite or finite is whether it is an unbounded or bounded metric space. An infinite universe (unbounded metric space) means that there are points arbitrarily far apart: for any distance d, there are points that are of a distance at least d apart. A finite universe is a bounded metric space, where there is some distance d such that all points are within distance d of each other. The smallest such d is called the diameter of the universe, in which case the universe has a well-defined "volume" or "scale."

A compact space is a stronger condition: in the context of Riemannian manifolds, it is equivalent to being bounded and geodesically complete. If we assume that the universe is geodesically complete, then boundedness and compactness are equivalent (by the Hopf–Rinow theorem), and they are thus used interchangeably, if completeness is understood.

If the spatial geometry is spherical, the topology is compact. For a flat or a hyperbolic spatial geometry, the topology can be either compact or infinite: for example, Euclidean space is flat and infinite, but the torus is flat and compact.

In cosmological models (geometric 3-manifolds), a compact space is either a spherical geometry, or has infinite fundamental group (and thus is called "multiply connected", or more strictly non-simply connected), by general results on geometric 3-manifolds.

Compact geometries can be visualized by means of closed geodesics: on a sphere, a straight line, when extended far enough in the same direction, will reach the starting point.

Note that on a compact geometry, not every straight line comes back to its starting point. For instance, a line of irrational slope on a torus never returns to its origin. Conversely, a non-compact geometry can have closed geodesics: on an infinite cylinder, which is a non-compact flat geometry, a loop around the cylinder is a closed geodesic.

If the geometry of the universe is not compact, then it is infinite in extent with infinite paths of constant direction that, generally do not return and the space has no definable volume, such as the Euclidean plane.

Open or closed
When cosmologists speak of the universe as being "open" or "closed", they most commonly are referring to whether the curvature is negative or positive. These meanings of open and closed, and the mathematical meanings, give rise to ambiguity because the terms can also refer to a closed manifold i.e. compact without boundary, not to be confused with a closed set. With the former definition, an "open universe" may either be an open manifold, i.e. one that is not compact and without boundary,[8] or a closed manifold, while a "closed universe" is necessarily a closed manifold.

In the Friedmann-Lemaître-Robertson-Walker (FLRW) model the universe is considered to be without boundaries, in which case "compact universe" could describe a universe that is a closed manifold.

The latest research shows that even the most powerful future experiments (like SKA, Planck..) will not be able to distinguish between flat, open and closed universe if the true value of cosmological curvature parameter is smaller than 10−4. If the true value of the cosmological curvature parameter is larger than 10−3 we will be able to distinguish between these three models even now.[9]

Flat universe
In a flat universe, all of the local curvature and local geometry is flat. It is generally assumed that it is described by a Euclidean space, although there are some spatial geometries that are flat and bounded in one or more directions (like the surface of a cylinder, for example).

The alternative two-dimensional spaces with a Euclidean metric are the cylinder and the Möbius strip, which are bounded in one direction but not the other, and the torus and Klein bottle, which are compact.

In three dimensions, there are 10 finite closed flat 3-manifolds, of which 6 are orientable and 4 are non-orientable. The most familiar is the 3-Torus. See the doughnut theory of the universe

In the absence of dark energy, a flat universe expands forever but at a continually decelerating rate, with expansion asymptotically approaching some fixed rate. With dark energy, the expansion rate of the universe initially slows down, due to the effect of gravity, but eventually increases. The ultimate fate of the universe is the same as that of an open universe.

A flat universe can have zero total energy and thus can come from nothing.[10][11]

Spherical universe
A positively curved universe is described by spherical geometry, and can be thought of as a three-dimensional hypersphere, or some other spherical 3-manifold (such as the Poincaré dodecahedral space), all of which are quotients of the 3-sphere.

Analysis of data from the Wilkinson Microwave Anisotropy Probe (WMAP) looks for multiple "back-to-back" images of the distant universe in the cosmic microwave background radiation. It may be possible to observe multiple images of a given object, if the light it emits has had sufficient time to make one or more complete circuits of a bounded universe. Current results and analysis do not rule out a bounded global geometry (i.e. a closed universe), but they do confirm that the spatial curvature is small, just as the spatial curvature of the surface of the Earth is small compared to a horizon of a thousand kilometers or so. If the universe is bounded, this does not imply anything about the sign[citation needed] of its curvature.

In a closed universe lacking the repulsive effect of dark energy, gravity eventually stops the expansion of the universe, after which it starts to contract until all matter in the observable universe collapses to a point, a final singularity termed the Big Crunch, by analogy with Big Bang. However, if the universe has a large amount of dark energy (as suggested by recent findings), then the expansion of the universe could continue forever.

Based on analyses of the WMAP data, cosmologists during 2004–2006 focused on the Poincaré dodecahedral space (PDS), but horn topologies (which are hyperbolic) were also deemed compatible with the data.

Hyperbolic universe
A hyperbolic universe is described by hyperbolic geometry, and can be thought of locally as a three-dimensional analog of an infinitely extended saddle shape. There are a great variety of hyperbolic 3-manifolds, and their classification is not completely understood. For hyperbolic local geometry, many of the possible three-dimensional spaces are informally called horn topologies, so called because of the shape of the pseudosphere, a canonical model of hyperbolic geometry.

Spherical Expanding Universe (Milne model)


Universe in an expanding sphere. The galaxies furthest away are moving fastest and hence experience length contraction and so become smaller to an observer in the centre.If the Universe is contained within an ever expanding sphere (which may have started from a single point), it can still appear infinite for all practical purposes. Because of length contraction the galaxies further away, which are travelling away from the observer the fastest, will appear smaller. In this way an infinite Universe fits within a finite sphere as long as the sphere is expanding continually. The question of whether the Universe is infinite can depend on the coordinate system used. For example, you could choose a coordinate system in which the galaxies are equally spaced out and don't have length contraction, in which case the Universe could be said to be infinite in size. Whichever galaxy the observer is on, the other galaxies moving away from it will appear length contracted. An observer can never get to the edge of the Universe if it is expanding at the speed of light. At the edge of the sphere matter becomes infinitely dense, but because it is moving away from the observer close to the speed of light due to time dilation its effect on the rest of the Universe is negligible. As the spherical Universe expands, matter that was near the edge is now in the middle of the sphere.

Proposed models
Various models have been proposed for the global geometry of the universe. In addition to the primitive geometries, these proposals include the:

Poincaré dodecahedral space, a positively curved space, colloquially described as "soccer ball shaped", as it is the quotient of the 3-sphere by the binary icosahedral group, which is very close to icosahedral symmetry, the symmetry of a soccer ball. This was proposed by Jean-Pierre Luminet and colleagues in 2003[3][12] and an optimal orientation on the sky for the model was estimated in 2008.[4]
Picard horn, a negatively curved space, colloquially described as "funnel-shaped", for the horn geometry.[5]

So obviously there is much debate about the physical shape of the universe. I have a hard time grasping some of the models but agree that any of them could be correct. But no matter what shape it is there has to be an edge or boundary. And if there is an edge then we must assume that there is something on the other side of it.

I've wondered what it would be like using a couple of different models. There is the most common and easy to imagine sphere universe. A round balloon like universe that expands just a balloon does while blowing it up. In this model galaxies aren't expanding through space but space is like oil with metal shavings (galaxies) in it and as the oil expands the shavings expand with it. So essentially the universe is getting larger. But how fast is it enlarging? If there is an edge and you reached out and touched it, how fast would it move away from your arm? And let's say you could keep pace with it. Could you stick your arm through it? Could you punch it and break your hand? What the hell is on the other side of it? Heaven? Hell? There can't be nothing there because there must be something for the universe to expand into. Or is there nothing? But what is nothing? If you drove your spaceship straight at the edge would you start to curve and ride the wall all the way around the unvierse? All the while thinking you were continuing on the same straight path. What does space look like from the outermost galaxies? Is one direction completely black and the other lit up from stars and galaxies? Or does the universe appear the same from anywhere in it?

Who knows? But it's some really cool stuff to think about.

“Whenever you find yourself on the side of the majority, it's time to pause and reflect.”

-Mark Twain
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10-01-2012, 02:55 PM
RE: The shape of the universe and what is at it's edge. Turn your noggins on.
I'm probably completely wrong but... follow me here

Imagine we had no concept of a 3d dimension. Now, imagine we where on top of a large sphere. (why not earth?). If we would keep walking, we would end up on the same spot. That would be weird to us but we could deduce a third dimension in which we travelled that enables us just to do that thing.

Now, I always picture our universe the same as in the story above but only with one more dimension. No matter in what direction we travel... up, down, left, right... We will eventually end up on the same spot.

Is this the truth... I might never know... but it helps me a lot.

side-note: No matter where you stand in this universe, you are always in the centre... This nicely explains some peoples attitude Big Grin

Observer

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10-01-2012, 03:05 PM
RE: The shape of the universe and what is at it's edge. Turn your noggins on.
(10-01-2012 02:55 PM)The_observer Wrote:  I'm probably completely wrong but... follow me here

Imagine we had no concept of a 3d dimension. Now, imagine we where on top of a large sphere. (why not earth?). If we would keep walking, we would end up on the same spot. That would be weird to us but we could deduce a third dimension in which we travelled that enables us just to do that thing.

Now, I always picture our universe the same as in the story above but only with one more dimension. No matter in what direction we travel... up, down, left, right... We will eventually end up on the same spot.

Is this the truth... I might never know... but it helps me a lot.

side-note: No matter where you stand in this universe, you are always in the centre... This nicely explains some peoples attitude Big Grin


Good stuff, good stuff. KC and I also wound up discussing 4th and even 5th, 6th, etc dimensions. It's just so damn hard to imagine what it's characteristics are. I've wondered if space time itself held the clues to other dimensions. I can't post youtube vids because the site is blocked here but if you haven't seen it, Dr. Quantum's Flat Land is really mindblowing. Imagine being a little 2D dot. Always moving forward adn back, side to side but no concept of up and down. We are like that now. If and when we find a 4th dimension (I'm not sure it's possible unless something in that dimension exposes it) our heads are gonna be so full of fuck.

“Whenever you find yourself on the side of the majority, it's time to pause and reflect.”

-Mark Twain
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10-01-2012, 03:15 PM
RE: The shape of the universe and what is at it's edge. Turn your noggins on.
(10-01-2012 03:05 PM)germanyt Wrote:  Dr. Quantum's Flat Land is really mindblowing.
Yes It was that vid that made me think about the above concept.

Well...
If a forth dimension is real, It could also explain the entanglement of certain events, and a whole bunch of other queer things like those "electrons being created" shit creationists jabber about.

Observer

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10-01-2012, 03:21 PM
RE: The shape of the universe and what is at it's edge. Turn your noggins on.
(10-01-2012 03:15 PM)The_observer Wrote:  
(10-01-2012 03:05 PM)germanyt Wrote:  Dr. Quantum's Flat Land is really mindblowing.
Yes It was that vid that made me think about the above concept.

Well...
If a forth dimension is real, It could also explain the entanglement of certain events, and a whole bunch of other queer things like those "electrons being created" shit creationists jabber about.

Particle physics is really crazy stuff. We know, well, we think we know that particles can appear from nowhere and disappear again. It's been worked on at the LHC (IIRC) for some time now. Perhaps the 4th dimension is where the particles are going and coming from. It's just so weird that we barely have any theories about what it's like. There there is the multi-verse theory. Where black holes create worm holes that tear through the fabric of space time and allow us to enter other dimensions that contain identical copies of our universe.

“Whenever you find yourself on the side of the majority, it's time to pause and reflect.”

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10-01-2012, 03:24 PM
RE: The shape of the universe and what is at it's edge. Turn your noggins on.
(10-01-2012 03:21 PM)germanyt Wrote:  There there is the multi-verse theory. Where black holes create worm holes that tear through the fabric of space time and allow us to enter other dimensions that contain identical copies of our universe.
The stuff of many-a-good sci-fi read!

Fantasy allowed!





























Those lame sheep-herders inventing the bible where SO unimaginative!!

Observer

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10-01-2012, 03:28 PM
RE: The shape of the universe and what is at it's edge. Turn your noggins on.
The big bang happened everywhere at once so, yes the universe appears to move outward from anywhere. The speed of the universe's expansion accelerates the further out you go. We haven't been able to view anything like an edge... if there is such a thing... so I couldn't speculate if there would be anything to put your hand through. Cool thought, though. Cool As far as we know, the universe is continually changing... the further out we see, we encounter remnants of the birth of stars that have long since exploded. And of course, we see what's left of the background radiation from the big bang. The further out, the faster you go, and the further back in time you can see.

You were high, weren't you? You and KC had yourselves a happy little dubbie-brother thing going on one night, right?

Uh huh. Sleepy S'cool.

A new type of thinking is essential if mankind is to survive and move to higher levels. ~ Albert Einstein
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10-01-2012, 03:51 PM (This post was last modified: 10-01-2012 03:54 PM by germanyt.)
RE: The shape of the universe and what is at it's edge. Turn your noggins on.
(10-01-2012 03:28 PM)kim Wrote:  The big bang happened everywhere at once so, yes the universe appears to move outward from anywhere. The speed of the universe's expansion accelerates the further out you go. We haven't been able to view anything like an edge... if there is such a thing... so I couldn't speculate if there would be anything to put your hand through. Cool thought, though. Cool As far as we know, the universe is continually changing... the further out we see, we encounter remnants of the birth of stars that have long since exploded. And of course, we see what's left of the background radiation from the big bang. The further out, the faster you go, and the further back in time you can see.

You were high, weren't you? You and KC had yourselves a happy little dubbie-brother thing going on one night, right?

Uh huh. Sleepy S'cool.


I've never heard the idea that the BB happened everywhere at once. I mean, obviously since our observable universe was once smaller than an atom one could have farted and stunk up the whole universe. But I've always imagined it as a ballon being blown up.

And that brings up an interesting thought. Is it possible that CBR is not being documented properly? Stars are visible to us that exploded millions of years ago. We know that the distances light travels makes the speed of light look slow by comparison. So maybe the radiation we measure from billions of light years away is the radiation that existed there billions of years ago. This may have already been considered by some nobel winning physicist but I'm just thinking out the box.

(10-01-2012 03:28 PM)kim Wrote:  You were high, weren't you? You and KC had yourselves a happy little dubbie-brother thing going on one night, right?

Uh huh. Sleepy S'cool.

And we actually were at work. In his office.






















Without a blunt.
(10-01-2012 03:24 PM)The_observer Wrote:  
(10-01-2012 03:21 PM)germanyt Wrote:  There there is the multi-verse theory. Where black holes create worm holes that tear through the fabric of space time and allow us to enter other dimensions that contain identical copies of our universe.
The stuff of many-a-good sci-fi read!

Fantasy allowed!







Those lame sheep-herders inventing the bible where SO unimaginative!!

Remember the TV show Quantum Leap?



If I was gonna wirte a bible 2000 years ago it probably would have resembled Starship Troopers or some shit.

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10-01-2012, 03:58 PM
RE: The shape of the universe and what is at it's edge. Turn your noggins on.
(10-01-2012 03:51 PM)germanyt Wrote:  I've never heard the idea that the BB happened everywhere at once. I mean, obviously since our observable universe was once smaller than an atom one could have farted and stunk up the whole universe. But I've always imagined it as a ballon being blown up.

There was no 'where' until the BB; the BB caused 'where', so it happened everywhere.

Quote:And that brings up an interesting thought. Is it possible that CBR is not being documented properly? Stars are visible to us that exploded millions of years ago.

Not sure I follow. Light left a star millions/billions of years ago. Then it exploded. The light that left is still traveling, the light that left as it exploded is right behind, the light that left after is exploded is right behind that.

Quote:We know that the distances light travels makes the speed of light look slow by comparison. So maybe the radiation we measure from billions of light years away is the radiation that existed there billions of years ago. This may have already been considered by some nobel winning physicist but I'm just thinking out the box.

Not sure I follow. How does the distance make the speed of light look slow? Because, at the speed of light, it takes a long time to go a long way?

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10-01-2012, 04:07 PM (This post was last modified: 10-01-2012 04:10 PM by germanyt.)
RE: The shape of the universe and what is at it's edge. Turn your noggins on.
(10-01-2012 03:58 PM)Chas Wrote:  
(10-01-2012 03:51 PM)germanyt Wrote:  I've never heard the idea that the BB happened everywhere at once. I mean, obviously since our observable universe was once smaller than an atom one could have farted and stunk up the whole universe. But I've always imagined it as a ballon being blown up.

There was no 'where' until the BB; the BB caused 'where', so it happened everywhere.

I disagree. Before our universe something existed I'm sure. I don't know what, but wrapping my head around there being nothing doesn't suit me. If believe if you could have been there there would have been something. I dont' know what kind of something. How big, how bright, hot hot, how much, etc I can't imagine.

Quote:And that brings up an interesting thought. Is it possible that CBR is not being documented properly? Stars are visible to us that exploded millions of years ago.

Not sure I follow. Light left a star millions/billions of years ago. Then it exploded. The light that left is still traveling, the light that left as it exploded is right behind, the light that left after is exploded is right behind that.

What I mean is that we base our ideas about expansion on CBR and redshift. What if the radiation coming from a billion light years away isn't really the radiation that is there now but is the radiation that was there a billion years ago and we are just now being able to detect it? So we could be basing our assumptions on radiation that hasn't been in a particular place for a billion years. Like I said, this now seems fairly elementary to me and I'm sure has been address by the scientific community.

Quote:We know that the distances light travels makes the speed of light look slow by comparison. So maybe the radiation we measure from billions of light years away is the radiation that existed there billions of years ago. This may have already been considered by some nobel winning physicist but I'm just thinking out the box.

Not sure I follow. How does the distance make the speed of light look slow? Because, at the speed of light, it takes a long time to go a long way?

Yep.

“Whenever you find yourself on the side of the majority, it's time to pause and reflect.”

-Mark Twain
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