Latitude and longitude have an arbitrary reference at the prime meridian and equator, but that's not a center: Finite surface, no center.Jheriko said:This is a bold claim. Is there an example for this that you can give or a proof of some kind?
It is a trivial claim, as Russ has shown.Jheriko said:This is a bold claim.
russ_watters said:Latitude and longitude have an arbitrary reference at the prime meridian and equator, but that's not a center: Finite surface, no center.
[late edit]
And no edge either.
Why would we bother with a cube? The poster requested "an example" and I provided what is probably the most popular and easy to recognize (since we're sitting on it).Loren said:I agree, but a cube is a different story, so, the statement doesn't hold for all geometries.
Jim, this "center of the universe" and "the big bang is an expansion from a point" mistake is very common and is debunked here with great regularity. Continuing to insist that there is a center is a waste of time. Better you would accept the fact that you are wrong and then try to figure out why your logic is leading you astray. That way, you'll learn something. Continuing to believe there's a center, you'll learn nothing.Jim Hasty said:This discussion, it appears to me, follows two different concepts: finite vs. infinite universe. Thetexan's core question though addresses the theory of the Big Bang, which assumes a singularity, an origin, or whatever you wish to call it for a point of beginning of the universe. Literature on this subject refers to the expansion of the universe as proceeding outward in relation to this point of origin (call it a center if you can accept that). So if we limit the discussion to the Big Bang, there should be a center (origin point) of the universe; whether it is finite or infinite. However, if you disagree, are you not off on another tangent: such as a different theory, multiverses, etc?
Artists are not physicists. The people who come up with these illustrations do not have a good understanding of physics. They draw whatever they want in the name of ' artistic license'. Illustrations and artist's concepts are not good things upon which to base your understanding of physics.curious Tom said:Numerous illustrations regarding time cones show the elsewhere to be the space into which the universe is expanding.
Yeah ! What he said.UncertaintyAjay said:Artists are not physicists. The people who come up with these illustrations do not have a good understanding of physics. They draw whatever they want in the name of ' artistic license'. Illustrations and artist's concepts are not good things upon which to base your understanding of physics.
phinds said:Jim, this "center of the universe" and "the big bang is an expansion from a point" mistake is very common and is debunked here with great regularity. Continuing to insist that there is a center is a waste of time. Better you would accept the fact that you are wrong and then try to figure out why your logic is leading you astray. That way, you'll learn something. Continuing to believe there's a center, you'll learn nothing.
Loren said:The concept of a center assumes an outside to the universe, which is a falsehood. It's natural to want to think of it that way since we mentally like to look at problems by stepping outside of them, turning them in our virtual hands, and examining them from all sides. However, this mental abstraction is a false reality. You can't be outside the universe (except in a science fiction novel).
As far as then balloon analogy goes, if you consider the skin of the balloon or better yet, a sphere, as a 2D representation of the universe, where would it's absolute 2D center be?
First off, there is no centre to the surface of a balloon. Think about it. If you still think there is one, please calculate it for a sphere of , say, radius 10cm. You'll find that you won't be able to.Loren said:As far as then balloon analogy goes, if you consider the skin of the balloon or better yet, a sphere, as a 2D representation of the universe, where would it's absolute 2D center be?
I disagree completely. You are doing exactly what I warned about in the discussion of the balloon analogy. You are taking the analogy to places it just does not logically go, and more to the point you are trying to apply that to reality also in a way that just doesn't work. It is NOT a matter of interpretation. This is the last I'll have to say on the subject. Believe what you believe but don't expect physicists to agree w/ you.Jim Hasty said:Lauren, I actually agree with you. But let me ask you a question: do you accept the notion there can be higher dimensions to the universe beyond the ones which we live in and can actually access? If so, then in your example, we live on the 2D surface and there is no center. But in the 3D world (which flatland 2D people do not live in) the center of the 3D universe is (0,0,0).
Here is a direct quote from phind's ' the balloon analogy':Jim Hasty said:I looked at your website and the 'balloon analogy' which is an example of my point. You are telling people there is 'no center' and 'no boundary' for the surface of the balloon - CORRECT! - for the analogy. But (and this is also a simple analogy) if you think of the balloon surface as 3-D residing on the surface of a 4-D sphere, then the center of the sphere is at coordinate (0,0,0,0). Or, if you take the view the balloon surface is 4-D; then the universe center could be at (0,0,0,0,0). There is no center for where we live (surface) but there is a center in a higher dimension. That's all I'm saying. The arguments seem to be over interpretation.
russ_watters said:Latitude and longitude have an arbitrary reference at the prime meridian and equator, but that's not a center: Finite surface, no center.
[late edit]
And no edge either.
phinds said:It is a trivial claim, as Russ has shown.
Loren said:I agree, but a cube is a different story, so, the statement doesn't hold for all geometries.
Jim Hasty said:Lauren, I actually agree with you. But let me ask you a question: do you accept the notion there can be higher dimensions to the universe beyond the ones which we live in and can actually access? If so, then in your example, we live on the 2D surface and there is no center. But in the 3D world (which flatland 2D people do not live in) the center of the 3D universe is (0,0,0).
UncertaintyAjay said:First off, there is no centre to the surface of a balloon. Think about it. If you still think there is one, please calculate it for a sphere of , say, radius 10cm. You'll find that you won't be able to.
Oops. Sorry. Must have misinterpreted that one. It's just that this is a very heated ' discussion', and I got a bit excited. hahaLoren said:Of course. That was my point, too.
Jheriko said:with all due respect i believe you are too quick to shoot these things down and that you haven't paid close attention to the detail of what i said.
at the risk of coming off with a similar poor tone to these comments, allow me to explain in more detail so that it is not so easy to make the mistakes.
i quite explicitly defined what i imagine a laymen means by 'finite' - bounded in the dimensions of the coordinate system under consideration. in his ideals the surface of a sphere like you describe is an /infinite/ surface because in the local coordinate spaces there are no bounds unless you are choosing a chart that has a seam (singularity) on it rather than multiply wrapping around the sphere (e.g. a cylindrical projection) - in which case we now have a finite area /with well defined bounds in all coordinates/ and so we can use the layman's understanding of what a centre is and there very much is one at 0 latitude and longitude (assuming we go from -pi to pi, -1/2 pi to 1/2 pi).
with regards the cube you can map a cube to a sphere and a sphere to a cube (any convex geometry to a sphere) so using a cube makes no difference to the nature of this, nor a dodecahedron or a cylinder. it just introduces a deformed version of the same coordinate system.
the other point that people try to make is that with the balloon analogy it has volume, and the volume has a centre. comparing this to volume in the universe completely missing the abstraction the balloon analogy makes to simplify things - specifically using 2D as a substitute for 3D because people struggle with visualising and understanding 4D representations. in that sense, if the universe was an unbounded 3-sphere then we have a 'hypervolume' inside of it which also very much has a centre in that 'fictional' 4-space - note, that this 4-space is not a minkowski style space-time but a 'fictional' euclidean 4-space, in the same sense that the 3-space the balloon is embedded is not a 2,1 space-time, but euclidean 3-space - or alternatively an extension of the sphere's local coordinate system that replaces intrinsic curvature with extrinsic curvature by embedding the system in a space with higher dimensionality.
now, if i am wrong, and you can construct a reasoned argument for why instead of a flat statement asserting that these things are wrong and that i simply do not understand, then i will consider it and hope that i have the good graces adjust my stance accordingly if it is a convincing argument.
again i apologise if my tone is poor. its very frustrating to see these kinds of comments, they paint a poor picture of the scientific community to laypeople and they are not uncommon - i have been guilty of this my self plenty too. its a natural way to behave when you are confident in your knowledge and weary of trying to explain the same things repeatedly.
I fully agree with the article - as far as the analogy. THERE IS NO CENTER FOR THE SURFACE OF A BALLOON.UncertaintyAjay said:Here is a direct quote from phind's ' the balloon analogy':
"The analogy is NOT intended to imply that our 3D universe is embedded in some 4D space (I’m not talking about 4D space-time but 4 dimensions of distance) "
Because I have nothing better to do, I counted, and in that article, it has been mentioned at least 4 times that there is no centre. There seems to be no contradiction.
Occasionaly it happens that somebody comes up with a new theory which can explain some observations better than any existing paradigm.Jim Hasty said:Shouldn't science take both points of view with an open mind? Otherwise we choose a particular road and never look at other possibilities.
Absolutely. I think the problem is that you are trying to imagine it with a center. THAT I cannot do. Well, that's not quite true. I suppose I could imagine it in exactly the same way I imagine unicorns, but who cares?Monsterboy said:Is imagination the big problem here ? @phinds can you imagine/visualize the big bang and the universe in the way you describe it in your mind ?
and in physics, that's what counts.I understand the evidence suggests that that there is no centre and that all the galaxies are simply moving away from each other ,not from a particular point in space
If you are going to try to visualize everything in quantum mechanics and cosmology, you are in for a lot of disappointment. What do you think a photon looks like, for example? You DO believe in photons, I assume?but i can't imagine/visualize the big bang in my mind ,perhaps it's simply because i never studied cosmology (i am not talking about balloon or any other analogy).
It seems to me you are suggesting that we give equal credence to General Relative and the theory that the Earth is flat.Jim Hasty said:Shouldn't science take both points of view with an open mind? Otherwise we choose a particular road and never look at other possibilities.
I have avoided insulating you. Please give me the same courtesy.phinds said:It seems to me you are suggesting that we give equal credence to General Relative and the theory that the Earth is flat.
It appears to me you prefer the 'flat earth' view and give no credence to GR.phinds said:It seems to me you are suggesting that we give equal credence to General Relative and the theory that the Earth is flat.
What?? That is just a juvenile attempt to get back at phinds.Jim Hasty said:It appears to me you prefer the 'flat earth' view and give no credence to GR.
rootone said:Occasionaly it happens that somebody comes up with a new theory which can explain some observations better than any existing paradigm.
In that case the new theory ought to be able to make some testable prediction which the old one does not, and if such testing verifies the prediction then the new theory will become considered as being more accurate.
However, there is no reason why 'alternative' theories should always be considered.
If an alternative theory doesn't explain anything any better than an existing theory does, it has no useful purpose.
There are often situations where some observed phenomena is not well explained by any particular theory, and when that is the case alternatives do get considered and tested for.
Dark matter for example is in that category, there are a number of proposals for what it might be, and various experiments ongoing in an attempt to determine if any of these are more likely, or whether some ideas can be discounted.[/Q