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Nanoose
12-21-2009, 11:23 AM
... is also infinite?
I'm having trouble understanding why the first necessarily implies the later. Can anyone help me out? I'm trying to google up an answer, but can't seem to find out why a spatially flat universe must also be infinite. No way it could be finite? Thx.

Tom Montgomery
12-21-2009, 11:27 AM
The universe is flat? I did not know that.

JimD
12-21-2009, 11:34 AM
Not to worry, Nanoose. Your chances of sailing off the edge of it are still very slim.

Kaa
12-21-2009, 11:37 AM
... is also infinite?
I'm having trouble understanding why the first necessarily implies the later. Can anyone help me out? I'm trying to google up an answer, but can't seem to find out why a spatially flat universe must also be infinite. No way it could be finite? Thx.

There is an underlying assumption that there are no "artificial" boundaries.

A line is, by definition, infinite -- unless you "cut" it and make it a segment. But a circle is finite without any necessity to bound it.

Spatially flat space (e.g. Euclidian space) is -- just like a line -- naturally infinite. A curved space (e.g. under spherical geometry) is naturally finite.

Kaa

Yeadon
12-21-2009, 11:58 AM
I really like this conversation. Thanks.

Nanoose
12-21-2009, 12:05 PM
Thanks, Kaa...but, as we know the universe had a beginning (big bang), how can it also be infinite? I'm probably mixing concepts here...but wouldn't an infinite line need infinite time? And, I thought actual infinites couldn't exist?

(doesn't "time" function as a 'cut' in the infinite line rendering it finite?)

capt jake
12-21-2009, 12:10 PM
This is indeed interesting. All the elements of a very heated debate. :) Unexplored worlds, religion, science, running out of fuel getting there, a debate by the right and left, does that make heaven bigger now? So many questions! :D

Keith Wilson
12-21-2009, 12:20 PM
but, as we know the universe had a beginning (big bang), Well, not quite. Assuming that's correct, it means that we don't and probably can't know anything about what, if anything, happened before the big bang. That's not the same thing as "the universe had a beginning".

But the idea about infinite space is simpler than you might think. Curved space can be finite without edges, without boundaries, by its nature. Consider Kaa's sphere. But for flat space to be finite, it would have to have an edge. That's all.

Tom Montgomery
12-21-2009, 12:22 PM
My understanding is that the WMAP data also supports the possibility of a horn topology as described by non-Euclidean Hyperbolic Geometry.

Just saying....

This is a topic where common words and common sense fail. The only language that adequately explains this stuff is mathematics of a sort I am confident none of us here understand.

Kaa
12-21-2009, 12:25 PM
Thanks, Kaa...but, as we know the universe had a beginning (big bang), how can it also be infinite? I'm probably mixing concepts here...but wouldn't an infinite line need infinite time?

Well, my understanding of these issues is certainly limited, but think of it this way. There is the concept of space -- not as in something outside of Earth's atmosphere, but as in a topological concept, a certain medium, if you wish, where certain (geometrical) relationships hold and certain rules apply.

Space doesn't need to contain anything -- it can perfectly well be empty of mass and energy.

Now, the big bang started up our universe which we understand to mean mostly mass and energy. The universe and the space are different things. Simplifying a lot, the universe exists in space. And we're now talking about the properties of the space in which the universe exists.

Now, if the space in which the universe exists is spatially flat (and it seems to be so, though physics isn't completely sure about that), it is infinite -- in the meaning that a point in that space can be arbitrarily far from another point in that space. For comparison note that, for example, in a sphere that is not true -- no point can be further than the diameter of the sphere from any other point.

But, speaking crudely again, our universe seem to expanding in spatially flat space which means it can go on expanding as much as it wants -- it won't curl back on itself. And, of course, the boundary of the universe is not (rather, not necessarily) the boundary of the topological space.

In reality this is more complicated. The two major factors are that mass affects space and it's unclear to which degree we can talk about properties of completely empty space and whether such a thing even exists; and the fact that the speed of light is an absolute limit.


And, I thought actual infinites couldn't exist?

Depends on what do you mean by "exist" :-)

Kaa

botebum
12-21-2009, 12:29 PM
We were taught in high school math that part of the definition of a line is that it is infinite. I once asked the teacher if a line had two sides and their answer was yes. Following that, wouldn't a line then be finite from side to side and can something be infinite and finite at the same time? If a line is infinite wouldn't it actually be a plane? The teacher couldn't answer. Can you? It still makes me wonder.
Another question- Can anything tangible ever be infinte or can infinite only exist conceptually?

Doug

Yeadon
12-21-2009, 12:31 PM
http://upload.wikimedia.org/wikipedia/commons/9/98/End_of_universe.jpg

I'm not going to get anything done today because of this.

Kaa
12-21-2009, 12:39 PM
We were taught in high school math that part of the definition of a line is that it is infinite. I once asked the teacher if a line had two sides and their answer was yes.

She was wrong.

The line that's infinite is an abstraction and has no width and so no two sides. It actually doesn't have sides at all.

In the same way a topological point has zero size. It doesn't have an area or a diameter or anything like that.


can something be infinite and finite at the same time?

Sure, no problem.


If a line is infinite wouldn't it actually be a plane?

Not at all. Infinity and number of dimensions are quite different things.


Can anything tangible ever be infinte or can infinite only exist conceptually?

What do you mean by "tangible"?

A photon emitted outwards at the boundary of the universe will fly forever, that is, for infinite time. Is that tangible?

Kaa

botebum
12-21-2009, 12:42 PM
Thanks Kaa. Clear as mud:confused::D

Doug

LeeG
12-21-2009, 12:43 PM
This is a topic where common words and common sense fail. The only language that adequately explains this stuff is mathematics of a sort I am confident none of us here understand.


I'll stick with food

Tom Montgomery
12-21-2009, 12:51 PM
When Good Mathematicians Turn Bad

"Psst, c'mere," said the shifty-eyed man wearing a long black trenchcoat, as he beckoned me off the rainy street into a damp dark alley. I followed.

"What are you selling?" I asked.

"Geometrical algebra drugs."

"Huh!?"

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"Stop right there," I interrupted. "I've never heard of inside- outers."

"Oh, man, you'll love 'em. Makes you feel like M.C. ever-lovin' Escher on a particularly weird day."

"Go on..."

"OK, your inside-outers, your arbitrary bilinear mappers, and here, heh, here are the best ones," he said, pulling out a large clear bottle of orange pills.

"What are those, then?" I asked.

"Givens transformers. They'll rotate you about more planes than you even knew existed."

"Sounds gross. What about those bilinear mappers?"

"There's a whole variety of them. Here's one you'll love -- they call it 'One Over Z' on the street. Take one of these little bad boys and you'll be on speaking terms with the Point at Infinity."

Peerie Maa
12-21-2009, 12:54 PM
We were taught in high school math that part of the definition of a line is that it is infinite. I once asked the teacher if a line had two sides and their answer was yes. Following that, wouldn't a line then be finite from side to side and can something be infinite and finite at the same time? If a line is infinite wouldn't it actually be a plane? The teacher couldn't answer. Can you? It still makes me wonder.
Another question- Can anything tangible ever be infinte or can infinite only exist conceptually?

Doug

I think that the issue is that a line has only one dimension, if it had thickness as well as length it would be either a surface ( two dimensions) or a solid ( a rod). That leads us to the conclusion that its thickness is zero but you can be on this side of it or on that side.
By the way you have reminded me of this book : Flatland:A Romance of Many Dimensions (http://en.wikipedia.org/wiki/Flatland), an interesting read if you can find it.
As to the infinite, I think that it can only be a concept by its nature.

Kaa
12-21-2009, 12:57 PM
This is a topic where common words and common sense fail. The only language that adequately explains this stuff is mathematics of a sort I am confident none of us here understand.

Oh, come on. It's not like we're talking quantum mechanics where having common sense is a rather big disadvantage :D

Humans actually grok topology up to 3-D quite well -- you kinda have to if you want to survive in a 3-D world. It's trivial to make topologically strange things like Mobius strips or even Klein bottles :-) And mariners should understand spherical geometry quite well.

As long as we don't get into higher dimensions or, say, fractal dimensions, most of the stuff should be fairly intuitive.

Kaa

Popeye
12-21-2009, 01:15 PM
Spatially flat space (e.g. Euclidian space) is -- just like a line -- naturally infinite. A curved space (e.g. under spherical geometry) is naturally finite.not exactly

space may be described using euclidean geometry , space itself is non euclidean

in non euclidean geometry , hyperbolic shapes are infinite

Popeye
12-21-2009, 01:16 PM
most of the stuff should be fairly intuitive.

there's the problem

Kaa
12-21-2009, 01:21 PM
space may be described using euclidean geometry , space itself is non euclidean

LOL.

E.g.:

http://mathworld.wolfram.com/EuclideanSpace.html
http://www.britannica.com/EBchecked/topic/194913/Euclidean-space
http://dictionary.reference.com/browse/Euclidean+space

Kaa

Popeye
12-21-2009, 01:29 PM
i see you have learned how to spell euclidean .. good .. but beyond that ,all you have there is a mathematical model used to describe space

Kaa
12-21-2009, 01:32 PM
all you have there is a mathematical model used to describe space

Not describe, but define.

Topological space is an abstraction.

Kaa

Popeye
12-21-2009, 01:34 PM
Not describe, but define.

nope

Pugwash
12-21-2009, 01:40 PM
http://home.u08.itscom.net/hedgehog/english/h2g22l.jpg

Popeye
12-21-2009, 01:47 PM
.. as we know the universe had a beginning (big bang), um no

the word on the street is , the reason we can't answer those questions is because the model (bb) is wrong to begin with:rolleyes:

the most recent thinking on this by physicists is we have something like a double sided universe , an 'inside' and an 'outside' which keep switching :cool:

sorry about dumbing it down a shade , but i got kaa to deal with :D

Kaa
12-21-2009, 02:12 PM
Get some tastier bait, Popeye :D

Kaa

LeeG
12-21-2009, 02:42 PM
could you two puff out your chests a bit more?

Kaa
12-21-2009, 02:58 PM
could you two puff out your chests a bit more?

You wanted some food..? Here:

http://www.georgehart.com/bagel/bagel0.jpg

:D

Kaa

pefjr
12-21-2009, 03:09 PM
At least they are not talking pink ponies and rhinestones? Dumb it down some more for me.

LeeG
12-21-2009, 03:45 PM
You wanted some food..? Here:

http://www.georgehart.com/bagel/bagel0.jpg

:D

Kaa

show off

WX
12-21-2009, 04:51 PM
http://images.fanpop.com/images/image_uploads/diskworld-picture-authors-535783_307_345.jpg

Anything above 4 dimensions does my head in. As for infinite, well whatever is out there inhabits infinite space...which also shorts a few neurons from time to time.

Pugwash
12-21-2009, 04:54 PM
Looks to me like the Ramtops are in the wrong place on that one, WX.

WX
12-21-2009, 04:59 PM
Yeah, it's not the best I could find...not a lot to choose from.
http://deltamualpha.org/img/EeePC_Wallpapers/Diskworld.jpg

Keith Wilson
12-21-2009, 05:01 PM
"It's no use, Mr. James; it's turtles all the way down!" :D:D

Boston
12-21-2009, 05:04 PM
E gads did someone bend a bagel into a double moebius
nice trick

ok wrench in the works time

if the big bang theory is all that why has it so consistently failed to predict anything very accurately
the back ground radiation for instance
when the theory originally predicted that it got it waaaaaaayyyyyyy wrong
still doesnt get it right as far as I remember
although its been a few years since I was in college

the eastern school of thought is more of a big bounce theory
neither works all that well and neither account for the inconsistencies in red shift or a number of other major sticky points

I kinda think old Edd Whitten or Maquao are more likely to be on the right track

cheers
B

Nanoose
12-21-2009, 05:17 PM
Well, my understanding of these issues is certainly limited, but think of it this way. There is the concept of space -- not as in something outside of Earth's atmosphere, but as in a topological concept, a certain medium, if you wish, where certain (geometrical) relationships hold and certain rules apply....



Kaa

thanks, but the question is regarding the universe, not space...er, I think. Rereading the text that originated my question, the author seems to be flipping back and forth from space to universe - as you point out, they are not one and the same....
i think it all just got more difficult...:(

"...the universe is spatially infinite...." - is he talking the universe, or space is infinite? The NASA site I read was talking about a flat universe...

Keith Wilson
12-21-2009, 05:19 PM
if the big bang theory is all that why has it so consistently failed to predict anything very accurately
the back ground radiation for instance Actually, the big bang theory predicted the background microwave radiation just about exactly; that's considered one of the major pieces of evidence in favor of it. Look here. (http://en.wikipedia.org/wiki/Cosmic_microwave_background_radiation)

Witten's a genuine grade-AAA certified genius, but I'll take string theory more seriously when it makes a prediction that can be tested. Any prediction.

johnw
12-21-2009, 05:34 PM
My understanding is that the WMAP data also supports the possibility of a horn topology as described by non-Euclidean Hyperbolic Geometry.


Known as horny space?

Boston
12-21-2009, 07:41 PM
ya I wouldn't depend to much on Wikipedia for to much technical information

I think we may be destined to disagreement

the big bang did not predict the background radiation accurately
yes it predicted "a" background radiation
but it got the measurement all wrong
way wrong actually
I seem to remember it predicted something like 40K and I think the real number was eventually discovered to be something in the area of 3K
I also seem to remember that several others had there own pet theories and manors of calculating the background radiation and almost all of them got it a lot closer, although the various theories seem to have gone the way of the Dodo. The BB theory is not really all that good and its chock full of holes but its the best we have so far.

put it this way
what if the red shift isn't Doppler effect
but Compton effect instead
kinda screws up the whole plan at that point
and thats just one glitch in the theory

changes the whole dynamics of the universe which in turn lends a whole new light to Nanoose's original question

I think we are limited to considering the shape of the observable universe and that shape must be curved if for no other reason than the wave form with which you observe it is also being effected by it.
Ends up a curve.

my two cents
carry on
B

Captain Blight
12-21-2009, 08:33 PM
Semi-related:
In my churning through the search for the Higgs boson, I came across something that seemed to make even less sense than the quantum physics normally does to me: If I'm reading all this right, then it would seem that at the moment of the Big Bang the strong nuclear force and the weak nuclear force and gravity and magnetism were all one and the same force?

Can I be reading this right? Could this even be theoretically possible?

WX
12-21-2009, 09:39 PM
Solar red shift and the Compton Effect. My knowledge of maths is not up to this but some of you may find it interesting.


http://resources.metapress.com/pdf-preview.axd?code=p40434r34656840r&size=largest

ingo
12-22-2009, 02:12 AM
Semi-related:
In my churning through the search for the Higgs boson, I came across something that seemed to make even less sense than the quantum physics normally does to me: If I'm reading all this right, then it would seem that at the moment of the Big Bang the strong nuclear force and the weak nuclear force and gravity and magnetism were all one and the same force?

Can I be reading this right? Could this even be theoretically possible?

With an appropriate theory everything is possible ;-)

Indeed the "standard big bang theory" says that all 4 basic forces were one.

At least directly after the Planck-time (5*10^-44 seconds). There can be made no predictions for the "time" between 0 and Planck-time since time itself did not exist as a continuum.

The first force that separated directly after Planck-time was gravity.

At 10^-35 seconds the strong nuclear force separated.

At 10^-12 seconds the weak nuclear force separated.

What was left was the electromagnetic force.

And please - do not talk about "before big bang" or "outside the universe" as long as you refer to our dimensions. Our spacetime does only exist in our universe. Or - to be more correct - our universe is defined as our spacetime.

bobbys
12-22-2009, 03:03 AM
I know most of youse are going to look at me for the answer on this but really i can be of no help..

However i used to be able to tell youse the lineups of the 60s Mets and Yankee teams but have forgot even that.

I never thought to much of Joe Pepitone by the way.....

bucheron
12-22-2009, 07:44 AM
She was wrong.

The line that's infinite is an abstraction and has no width and so no two sides. It actually doesn't have sides at all.

In the same way a topological point has zero size. It doesn't have an area or a diameter or anything like that.


Kaa

E. F. Schumacher and a few of his smartie fellow junior academics useta refer to one of their bosses as "die punkt" ie german for "the point".

In that he had position but no substance. :D:D:D

Tangible, literally, able to be touched, therefore a physical reality.

Keith Wilson
12-22-2009, 08:20 AM
the big bang did not predict the background radiation accurately
yes it predicted "a" background radiation
but it got the measurement all wrong
way wrong actually This is 100% dead false. The nearly-exact prediction of the cosmic background radiation is one of the strongest pieces of evidence supporting the big bang theory. At least two Nobel prizes in physics have been awarded for his work - Penzias and Wilson in 1978 and George Smoot in 2006.. You don't trust Wikipedia? They're quite right in this case, but try Lawrence Berkeley Labs (http://www.lbl.gov/Publications/Nobel/) and the Nobel Prize Committee (http://nobelprize.org/nobel_prizes/physics/laureates/1978/press.html) . Here's an explanation about how the Cosmic Background Radiation fits the theory almost exactly , from Smoot's group at Lawrence Berkeley Labs. (http://aether.lbl.gov/www/science/cmb.html), and an intro from the University of Chicago. (http://background.uchicago.edu/~whu/beginners/introduction.html)

Sorry, but what you "seem to remember" is simply incorrect.

Popeye
12-22-2009, 08:29 AM
the big bang theory predicted the background microwave radiation just about exactly; that's considered one of the major pieces of evidence in favor of it. .

nope

it's actually one of the major problems , cmbr is way to smooth , huge problem

Popeye
12-22-2009, 08:32 AM
At least two Nobel prizes in physics have been awarded for his work - Penzias and Wilson in 1978 ..

all those guys did was find the cosmic background radiation by accident , they thought for a long time it was simply noise coming from a receiver :rolleyes:

huisjen
12-22-2009, 08:49 AM
Does this help?

http://www.wimp.com/knownuniverse/

Dan

Keith Wilson
12-22-2009, 09:33 AM
cmbr is way to smooth , huge problem Reference?

Popeye
12-22-2009, 09:41 AM
reference sure, the one and the same wiki article(s) you posted , drill down a bit further .. see the problems cited .. re: baryons

as time goes on , theories will either be supported or they will flop , bb is a bit of a dinosaur keith


This is 100% dead false. i'm thinking you might want to revise this also , i'm just say'n :rolleyes:

Keith Wilson
12-22-2009, 09:50 AM
Nope. While there are plenty of things we don't yet understand, Mr. Boston was 100% dead wrong.
Precise measurements of cosmic background radiation are critical to cosmology, since any proposed model of the universe must explain this radiation. The CMBR has a thermal black body spectrum at a temperature of 2.725 K, thus the spectrum peaks in the microwave range frequency of 160.2 GHz, corresponding to a 1.9 mm wavelength.[nb 1] The glow is almost but not quite uniform in all directions, and shows a very specific pattern equal to that expected if the inherent randomness of a red-hot gas is blown up to the size of the universe. In particular, the spatial power spectrum (how much difference is observed versus how far apart the regions are on the sky) contains small anisotropies, or irregularities, which vary with the size of the region examined. They have been measured in detail, and match what would be expected if small thermal fluctuations had expanded to the size of the observable space we can detect today. This is still a very active field of study, with scientists seeking both better data (for example, the Planck spacecraft ) and better interpretations of the initial conditions of expansion.

Although many different processes might produce the general form of a black body spectrum, no model other than the Big Bang has yet explained the fluctuations. As a result, most cosmologists consider the Big Bang model of the universe to be the best explanation for the CMBR.We will no doubt find out more in the future, but as things stand today, accurate prediction of the CMBR is one of the strongest pieces of evidence in favor of the big bang.

Popeye
12-22-2009, 10:16 AM
Mr. Boston was 100% dead wrong. um , no


accurate prediction of the CMBR is one of the strongest pieces of evidence in favor of the big bang... and double no

from the wiki article ..

"The background radiation is exceptionally smooth, which presented a problem in that conventional expansion would mean that photons coming from opposite directions in the sky were coming from regions that had never been in contact with each other.

and this ..

During the 1970s and 1980s, various observations showed that there is not sufficient visible matter in the Universe to account for the apparent strength of gravitational forces within and between galaxies. This led to the idea that up to 90% of the matter in the Universe is dark matter that does not emit light or interact with normal baryonic matter. In addition, the assumption that the Universe is mostly normal matter led to predictions that were strongly inconsistent with observations. In particular, the Universe today is far more lumpy and contains far less deuterium than can be accounted for without dark matter. While dark matter was initially controversial, it is now indicated by numerous observations: the anisotropies in the CMB, galaxy cluster velocity dispersions, large-scale structure distributions...

:rolleyes::rolleyes:

Keith Wilson
12-22-2009, 10:33 AM
Nope. Look at the anisotropy section. The variations are what the theory predicts. Again, from the same article (emphasis added):
Two of the greatest successes of the big bang theory are its prediction of its almost perfect black body spectrum and its detailed prediction of the anisotropies in the cosmic microwave background. The recent Wilkinson Microwave Anisotropy Probe has precisely measured these anisotropies over the whole sky down to angular scales of 0.2 degrees. These can be used to estimate the parameters of the standard Lambda-CDM model of the big bang.
We are finding out more all the time, obviously, and no doubt current theory will have to be revised. But the fact that the big bang very, very accurately predicts the CMBR really is one of the strongest pieces of evidence in its favor.

Popeye
12-22-2009, 10:38 AM
could you two puff out your chests a bit more?

hmmm .. when i asked you in another thread if you could explain where low frequency sound comes from , you said it came from swiss bells .. sounds like a terrible assumption to me..

stay tuned

Nanoose
12-22-2009, 10:38 AM
May I politely interrupt our regular programming :rolleyes: to ask if either of you two yahoos can help me with my question? I'll retract what I said re bb...understanding that, once again, we are not sure the universe had a beginning. IF the universe had a beginning, that indicates a line 'segment' (I think), and therefore, how can spatially flat necessity infinite? Thx.

Keith Wilson
12-22-2009, 10:49 AM
Deb, the point is that it's a geometry question. Using it to draw any conclusion about the real universe is dubious at best. A "flat" three-dimensional space is infinite unless it somehow has a boundary. A curved one is not; it closes back in on itself. It's pretty much impossible for human beings to visualize curved 3-dimensional space. See Yeadon's diagrams in post #2 for two-dimensional analogues.

Popeye
12-22-2009, 10:52 AM
IF the universe had a beginning, that indicates a line 'segment' (I think), and therefore, how can spatially flat necessity infinite? .

the answer is yes , it would have to be flat to be infinite , zero curvature

and there is keiths problem , bb fails to explain missing mass

ingo
12-22-2009, 11:02 AM
um , no

.. and double no

from the wiki article ..

"The background radiation is exceptionally smooth, which presented a problem in that conventional expansion would mean that photons coming from opposite directions in the sky were coming from regions that had never been in contact with each other.

and this ..

During the 1970s and 1980s, various observations showed that there is not sufficient visible matter in the Universe to account for the apparent strength of gravitational forces within and between galaxies. This led to the idea that up to 90% of the matter in the Universe is dark matter that does not emit light or interact with normal baryonic matter. In addition, the assumption that the Universe is mostly normal matter led to predictions that were strongly inconsistent with observations. In particular, the Universe today is far more lumpy and contains far less deuterium than can be accounted for without dark matter. While dark matter was initially controversial, it is now indicated by numerous observations: the anisotropies in the CMB, galaxy cluster velocity dispersions, large-scale structure distributions...

:rolleyes::rolleyes:

Background radiation has nothing to do with dark matter. And dark matter is not a problem of big bang theory but of cosmological models after the big bang. The mass of the universe is critical for the question if the universe is expanding or colapsing or whatever. And the mass of the visible universe is too small to fit with the measured data. Therefore we are looking for more mass.

BTW, "dark matter" is not black or something like that. "dark" is a description that it does not interact very much with photons or other known matter.

Anyway, if there is somethink like dark matter, it would have been created in the big bang. But the big bang without dark matter would have been a big bang, too ;-)

Popeye
12-22-2009, 11:06 AM
the fact that the big bang .. predicts the CMBR really is one of the strongest pieces of evidence in its favor.

this is an assumption , not evidence

cmbr comes from where ?

Popeye
12-22-2009, 11:08 AM
dark matter is not a problem of big bang theory but of cosmological models after the big bang.

are you alright ? :rolleyes::D

ingo
12-22-2009, 11:10 AM
are you alright ? :rolleyes::D

I studied theoretical astrophysics...

Keith Wilson
12-22-2009, 11:21 AM
this is an assumption , not evidenceNo. Once again, there are many features of the observed CMBR which are predicted accurately by the big bang. The spectrum (the intensity of radiation at various frequencies) - is exactly that the theory predicts, as is the anisotropy (the variation in the background radiation). When detailed observations of the physical world correspond to the predictions of a theory, this is evidence in favor of the theory. It is not an "assumption."

Ingo, if you have the patience, maybe you could help us out here. I got into this wrangle when Boston claimed that the big bang did not accurately predict the microwave background radiation, which AFAIK is dead wrong. Now Popeye has started posting zen koans again. You may be the only one here who really understands this.

ingo
12-22-2009, 11:21 AM
May I politely interrupt our regular programming :rolleyes: to ask if either of you two yahoos can help me with my question? I'll retract what I said re bb...understanding that, once again, we are not sure the universe had a beginning. IF the universe had a beginning, that indicates a line 'segment' (I think), and therefore, how can spatially flat necessity infinite? Thx.

First, the universe is not spatially flat according to measured data and general theory of relativity. Masses do bend the space globally. Local, you have a cartesian space (what you call "flat") but global, you have a minkowski space (definitelly not flat).

The question if a real space is infinite (are we talking about the universe or about mathematics?) can't be answered by it's metric.
An aquarium is cartesian and finite.

Nanoose
12-22-2009, 11:27 AM
Thanks, Ingo....but NASA seems to say the universe is flat, or am I misunderstanding this? I appreciate your help here...

http://map.gsfc.nasa.gov/universe/uni_shape.html

Also, I think you are saying an actual (material) infinite cannot exist. Correct?

ingo
12-22-2009, 11:35 AM
Nanoose, what do you mean by "infinite". There are two possible definitions:

a) if you just go ahead, you do never reach an end in any direction

b) if you have two locations A and B there is allways a location C that has a greater distance to A than A to B

The difference is, that for example the surface of a sphere is (in two dimensions) infinite according to a) but not to b) If A is the one pole and B the other, there is no C that has a greater distance.

As far as we know, the universe is infinite in the sense of a) but not b)

Neither theory nor measurements show a border of the universe.

Keith Wilson
12-22-2009, 11:41 AM
Ah, OK - Sorry Deb, I should have read the article. It's not just a geometrical point. Listen to Ingo, he knows what he's talking about. Beware, though, the math rapidly gets quite complicated.

Nanoose
12-22-2009, 11:48 AM
Thanks, Keith.

INGO: an earlier poster (Kaa, I believe) differentiated between space and the universe. Perhaps that is relevant.

Also, the quote I am trying to understand is regarding a "spatially infinite universe". If I am right to distinguish between space and the universe, what the heck does that quote mean?

Again, many thanks.

ingo
12-22-2009, 11:56 AM
Thanks, Ingo....but NASA seems to say the universe is flat, or am I misunderstanding this? I appreciate your help here...

http://map.gsfc.nasa.gov/universe/uni_shape.html

Also, I think you are saying an actual (material) infinite cannot exist. Correct?

They are talking about something different. Even the Nasa has no doubt that there is no border of the universe and that it is infinite in the sense of a) above.

The question is - simplified -, if the minkovsky space is in the middle a cartesian space all over the universe or if there is a global bending.

Example: The given one of the two photons that start parallel.
1) It is no question they never come to a border of the universe. 2) it is no question they fly not parallel if one of them passes a mass (this was observed by Arthur Eddington in 1919 at a solar eclipse).
3) It is no question, the universe is expanding
4) But it is the question what they do when the mass is equally distributed in the universe (what is not true; we have stars). Do they meet? Do they fly parallel forever? Or are they flying away from each other?

Or in other words: does the universe expand in the same speed or does the expanding slow down or does the expanding speed up?

ingo
12-22-2009, 12:03 PM
Thanks, Keith.

INGO: an earlier poster (Kaa, I believe) differentiated between space and the universe. Perhaps that is relevant.

Also, the quote I am trying to understand is regarding a "spatially infinite universe". If I am right to distinguish between space and the universe, what the heck does that quote mean?

Again, many thanks.

if you talk about real space (that is where wo could go or measure something or get information about), the real space is the universe. There is no outside in this sense.

Anyway you can philosophy about parallel universes or multiverses and what is the thing where all these ar "in". But this "space" has nothing to do with reality since it does not interact with our world. Science can only talk about things that can be observed/measured in principle.

Nanoose
12-22-2009, 12:07 PM
OK...so if the universe had a beginning, how can it be infinite?

Kaa
12-22-2009, 12:11 PM
Or in other words: does the universe expand in the same speed or does the expanding slow down or does the expanding speed up?

Wasn't this question answered a few years ago by the team which looked for supernova signatures? They came to the conclusion that the universe's expansion is speeding up -- which led to a large amount of hand-wringing and head-scratching in the cosmological community...

Kaa

Kaa
12-22-2009, 12:12 PM
OK...so if the universe had a beginning, how can it be infinite?

As geometric analogies go, a line is infinite at both ends, a segment is bounded at both ends, but a ray is bounded at one end and infinite at the other end.

Kaa

Hollingsworth
12-22-2009, 12:18 PM
To cross-pollinate this thread with another, perhaps the universe didn't so much bang into existence as much as it popped. Its topography, therefore, might be something more akin to this:

http://www.istockphoto.com/file_thumbview_approve/5499366/2/istockphoto_5499366-popcorn-kernel.jpg

I like my universe with salt and butter.

Kaa
12-22-2009, 12:21 PM
if you talk about real space (that is where wo could go or measure something or get information about), the real space is the universe. There is no outside in this sense.

Nanoose, you have to be careful with terminology, that's a source of much confusion.

"Space" can mean topological space which is mathematical abstraction with certain properties (e.g. curvature).

"Space" can also mean "real space" in which we actually exist. It is a much messier thing. At the moment physics treats is as a four-dimensional space (aka Minkowski space): three "normal" dimensions plus time. Moreover, according to general relativity, gravitation bends this space -- that is, introduces local curvature. So the "real space" is lumpy, it's not isotropic (same everywhere).

A separate question is whether besides local lumpiness there is global curvature (e.g. Earth is locally lumpy, but globally it's a sphere) -- and it looks, again, at the moment, that there is no global curvature.

As to "infinite", as Ingo says, it depends on how do you define infinity. If at the universe boundary you emit a photon outwards it should fly forever without hitting any boundaries or coming back to its origin. It is sufficient to call the universe infinite?

Kaa

Kaa
12-22-2009, 12:24 PM
To cross-pollinate this thread with another, perhaps the universe didn't so much bang into existence as much as it popped. Its topography, therefore, might be something more akin to this:

http://www.istockphoto.com/file_thumbview_approve/5499366/2/istockphoto_5499366-popcorn-kernel.jpg

I like my universe with salt and butter.

I prefer fractal foam :D

http://i296.photobucket.com/albums/mm161/kaa_photobucket/Fractal_foam.jpg

Kaa

Nanoose
12-22-2009, 12:28 PM
Yes, Kaa....I'm seeing the terminology is part of my problem....beyond the fact that it is challenging to get my head around.

Again, my real issue is with the idea that a spatially flat universe is necessarily infinite. My need is to say either, "yes - true", or "no - incorrect", and I'm not feeling like I'm any closer to being able to say one or the other, and much less understanding why. You all may have already helped me with it, and in my mega-confusion, I've just missed it....:(

If so, once again in really simple language, please. Thx.

ingo
12-22-2009, 12:45 PM
OK...so if the universe had a beginning, how can it be infinite?

Why not? It is not infinite in time maybe, but in space. What makes me some pains since they are not different. And as i posted earlier, we do not know anything about the time between zero and Planck-time since our concept of time does not fit there.

Kaa
12-22-2009, 12:47 PM
Again, my real issue is with the idea that a spatially flat universe is necessarily infinite. My need is to say either, "yes - true", or "no - incorrect", and I'm not feeling like I'm any closer to being able to say one or the other, and much less understanding why. You all may have already helped me with it, and in my mega-confusion, I've just missed it....:(

If so, once again in really simple language, please. Thx.

In simple language, spatially flat space has no natural boundaries. It just goes on forever. You can make boundaries (e.g. Ingo's aquarium), but space by itself is not bounded.

Compare it to a sphere (which has global positive curvature). The space itself is contained, you can't get arbitrarily far away. On a plane (spatially flat 2-D space) you can get as far from a specific point as you like. On a sphere's surface (spatially curved 2-D space) you cannot.

That's why we would call a plane's surface "infinite" and a sphere's surface "not infinite".

Kaa

ingo
12-22-2009, 12:50 PM
Wasn't this question answered a few years ago by the team which looked for supernova signatures? They came to the conclusion that the universe's expansion is speeding up -- which led to a large amount of hand-wringing and head-scratching in the cosmological community...

Kaa

This is indeed the question that the NASA asks.

Popeye
12-22-2009, 12:58 PM
When detailed observations of the physical world correspond to the predictions of a theory, this is evidence in favor of the theory. It is not an "assumption.".

so then you will have no difficulty with a simple question ..

where does cmbr come from ?

P.I. Stazzer-Newt
12-22-2009, 12:59 PM
I prefer fractal foam :D

......

Kaa

http://www.sgeier.net/fractals/fractals/01/Foam.jpg when linked as an image from wouldntboat.com yields a polite message


I am happy to share my artwork with the world for free but if you'd like to put it on your web site then you should really download a local copy.........

Man's got a point.

Popeye
12-22-2009, 01:02 PM
if there is somethink like dark matter, it would have been created in the big bang.

good point ..

describe how bb 'created' the dark matter please

Popeye
12-22-2009, 01:07 PM
Background radiation has nothing to do with dark matter. :confused:

even though dark matter is indicated by observations of the background radiation ?

:rolleyes:

Keith Wilson
12-22-2009, 01:13 PM
where does cmbr come from ? The conventional view is that it's left over from shortly after the big bang, the point when matter and energy became seprate things, although red-shifted considerably by the expansion of the universe.

Nanoose
12-22-2009, 01:16 PM
Many thanks, Kaa.

ingo
12-22-2009, 01:16 PM
Yes, Kaa....I'm seeing the terminology is part of my problem....beyond the fact that it is challenging to get my head around.

Again, my real issue is with the idea that a spatially flat universe is necessarily infinite. My need is to say either, "yes - true", or "no - incorrect", and I'm not feeling like I'm any closer to being able to say one or the other, and much less understanding why. You all may have already helped me with it, and in my mega-confusion, I've just missed it....:(

If so, once again in really simple language, please. Thx.

In mathematics, cartesian space is infinite.

Proof by contradiction:

WLOG we look at a one-dimensional cartesian space S. This has a border a point A. Any other point B has a distance to A. If you take two times the distance from B to A you come to a point C that is not part of S. This is a contradiction to the axiom of linearity. q.e.d.

Simple ;-)

If physicists say something can be described with a mathematical concept they do not mean that reality follows mathematics but that this a usefully concept.

Kaa
12-22-2009, 01:18 PM
http://www.sgeier.net/fractals/fractals/01/Foam.jpg when linked as an image from wouldntboat.com yields a polite message...


Man's got a point.

Thanks -- fixed that.

Kaa

Nanoose
12-22-2009, 01:19 PM
Why not? It is not infinite in time maybe, but in space. What makes me some pains since they are not different. And as i posted earlier, we do not know anything about the time between zero and Planck-time since our concept of time does not fit there.

Time and space (the material) seem to be linked/connected. So, I am trying to imagine a beginning to time but no beginning to space. If the material always concretely existed, how does that work without time? :(

Popeye
12-22-2009, 01:19 PM
..when Boston claimed that the big bang did not accurately predict the microwave background radiation, which AFAIK is dead wrong. .

i think it has been measured as 2.7 k :) , um , which prediction (http://en.wikipedia.org/wiki/Timeline_of_cosmic_microwave_background_astronomy) corresponds with this observation ?

Popeye
12-22-2009, 01:25 PM
The conventional view is that it's (cmbr) left over from shortly after the big bang..

yes , so , is this an assumption ?

ingo
12-22-2009, 01:33 PM
The conventional view is that it's left over from shortly after the big bang, the point when matter and energy became seprate things, although red-shifted considerably by the expansion of the universe.

No. It is left from the time when the universe became transparent. This was about 380,000 years after the big bang. The temperature was now below 3000 K and electric neutral atoms begin to exist (they had there electrons), especially hydrogen. They do not interact much with photons and therefore photons can fly a long distance. Before there was a plasma with free electrons and this is not transparent at all.

Matter as we know it existed at 10^-6 seconds after the big bang. hadrons like protons and neutrons.

When we look at the background radiation, we look at this plasma. Just take this 3000 K and make a red-shift translation.

ingo
12-22-2009, 01:41 PM
Time and space (the material) seem to be linked/connected. So, I am trying to imagine a beginning to time but no beginning to space. If the material always concretely existed, how does that work without time? :(

There is also a beginning of space. When the universe was smaller than the Planck-length (1.6 * 10^-35m what is 0,000000000000000000000000000000000016 metres) space did not exist as we know it. The Planck-lenth is the ultimate limit for space as the Planck-time is for time.

Material came a lot later than Planck-time...

Canoez
12-22-2009, 01:52 PM
you wanted some food..? Here:

http://www.georgehart.com/bagel/bagel0.jpg

:d

kaa

NOOOOOooo!!!! NOT THE INFINITE BAGEL!!!!

ingo
12-22-2009, 01:53 PM
:confused:

even though dark matter is indicated by observations of the background radiation ?

:rolleyes:


Yes, even though if. The big bang is about the beginning of the universe. The first second mainly. Background radiation cames several hundred thousand years later.

Keith Wilson
12-22-2009, 02:27 PM
It is left from the time when the universe became transparent. This was about 380,000 years after the big bang.Thanks.

Popeye
12-22-2009, 02:30 PM
yes , thanks for adding to the mountain of anomalies

flatness, too smooth, no boundary..

lovely theory

ingo
12-22-2009, 02:50 PM
yes , thanks for adding to the mountain of anomalies

flatness, too smooth, no boundary..

lovely theory

It is a lovely theory since it does fit the data better than any other theory i know. But feel free to present a better theory for the beginning of the universe. Science is about to be sceptic about theories.

Boston
12-22-2009, 08:46 PM
some of you folks seriously need to reevaluate quoting Wikipedia
its mostly bunk
if you would like to have a serious discussion about what was once one of my favorite topics then lets at least agree to use cited and referenced works as a basis for our discussion

statement
the big bang theory did not accurately predict the background radiation nor does it explain the inconsistency between that radiation and mass/energy density variations found throughout the known universe

citation
Editor: Haselhurst (http://open-site.org/profiles/haselhurst.html) ( Physics Essays Volume 10, Number 2, June 1997. William C. Mitchell)




The microwave background radiation (MBR), that is received uniformly from all directions of space, considered by many to be the most important evidence in support of Big Bang Theory, may be inconsistent with that theory.
In addition to the previous comment that one would expect the observed gigantic galactic formations to cause irregularities in the isotropy of MBR reception, the observed spectrum of the MBR, corresponding to a near perfect black body temperature of 2.7 K, doesn't agree very well with temperatures predicted by various Big Bang theorists. Those predictions had varied over a range of 5 to 50 K. (26) History also shows that some Big Bang cosmologists' "predictions" of MBR temperature have been "adjusted" after-the-fact to agree with observed temperatures.

The prediction of 5 K (by Ralph Alpher and Robert Herman in 1948), (27) which has been selected as a basis for agreement with the observed temperature, was made by those who had accepted a Big Bang scenario that included concepts that were incorrect. Those included the idea that all of the elements of the universe were produced in the Big Bang, which was later determined to be erroneous.
If the temperature of the universe was at absolute zero, all matter would collapse. The temperature of radiation from space might reasonably be expected to be some small number of degrees above that temperature. In fact, some physicists (including Sir Arthur Eddington in 1926 and Andrew McKeller in 1942)(28) had estimated temperatures in the range of 2 to 3 K; closer to that of the MBR than has been estimated by Big Bang cosmologists.

According to Big Bang theorists, the "decoupling era", from whence MBR is said to have originated, may have lasted at least several hundred thousand years. (29) It has occurred to me that, if radiation comes to us directly from that period, later radiation would have lower source temperature and less red shift, resulting in distortion, "smearing", (24) of the postulated black body spectrum from the decoupling. Big Bang theorists may have assumed that the temperature and red shift changes of that period would cancel; but unless the universe had linear (fixed-rate) expansion, that cancellation could not be perfect. Because Big Bang theorists believe, not in a fixed rate of expansion, but in a non-linear decelerating expansion, it would seem reasonable to suppose that a less than perfect black body spectrum might be received from the Big Bang decoupling than that which is observed.
Smearing of a black body spectrum from the decoupling would also result if the shape of the Big Bang universe were less than perfectly spherical during that period. Although Big Bang advocates believe in that smoothness, it may be difficult for others to accept an explosion of such symmetry.

If MBR from the decoupling had caused thermal equalization (thermalization) of the matter of the space that surrounds us, as other theorists have suggested, and that matter were quite remote, the large irregularities of galactic formations might be expected to cause fairly large directional variations of the MBR. If the MBR is radiated from thermalized matter relatively close to us (but perhaps outside of our galaxy), the MBR might possess the observed isotropy. However, the possibility should not be overlooked that, as the work of Eddington, McKeller and others indicates, the observed MBR may be the result of sources of
energy other than the Big Bang decoupling.

Some Big Bang cosmologists have contended that thermalization of surrounding space could not produce a spectrum so closely resembling that of black body radiation. However there is theoretical support for the existence of particles in space (called whiskers) (30-32) that in turn supports the possibility of thermalization. Physical evidence of these particles has been found in meteorites that have struck the earth. (33,34)

Further doubt about the Big Bang as a source of the MBR results from consideration of the amplitude of MBR signal strength received here on earth. Calculations indicate that the received energy may be orders of magnitude lower than would be expected from the enormous energy release of the postulated Big Bang decoupling. (24)
According to Big Bang Theory, positively curved space provides the explanation for omnidirectional reception of MBR from the decoupling. However, characteristics of the positively curved space of a closed universe cannot be ascribed to the flat or somewhat open universe that is accepted by the majority of Big Bang theorists.

As presented above, the closed Big Bang universe would seem to be ruled out by age and density considerations. But if that had not been the case, and space were positively curved as postulated for the closed Big Bang universe case, neutrinos from the Big Bang would be raining on us as well as photons. Those have not been detected. By similar reasoning, in a Big Bang universe of positively curved space, rather than being "clumped" at great distances (as they are perceived to be by the presently accepted interpretation of red shift data), quasars would be more evenly distributed in direction, distance and speed. If that were found to be true it might tend to deny one of the alleged proofs of Big Bang Theory, that of an evolving universe.

Photons [that is, electromagnetic radiation (EMR) in the infrared region] are believed to originate from the Big Bang decoupling, to be red-shifted by about 1,000, and to be received from all directions of space as MBR. According to Big Bang Theory, neutrinos are also said to originate from the Big Bang, but at a much earlier time. They, like the MBR, are believed to fill the space that surrounds us. According to quantum wave theory, although they are particles rather than EMR, they are considered to have a red shift much greater than that of Big Bang photons. Their energy is therefore too low to allow their detection: their frequency below the capability of available technology. Although neutrinos from nearby sources (from the sun and from Supernova 1987A) have been detected, the treatment of Big Bang neutrinos as waves is said to provide an explanation for the lack of their detection. However, the application of wave theory to neutrinos, but not to other particles (electrons, protons, neutrons, etc.) believed to have originated in the Big Bang at or before the time of the decoupling, appears to present a logical inconsistency.
It would seem that, upon consideration of the available evidence, rather than supporting Big Bang Theory, the presence of MBR might actually be counted against it. It seems more reasonable to postulate natural radiation from matter or energetic processes in relatively nearby space as the source of MBR.

Boston
12-22-2009, 08:47 PM
references to the previous




1. P. Davies, Superforce (Simon & Schuster, NY, 1984).
2. E. P. Tryon, Nature (14 December 1973).
3. A. H. Guth, and Paul J. Steinhardt, Sci. Am. (May 1984).
4. A. Linde, New Scientist (7 March 1985).
5. M. Rees and J. Silk, Sci. Am. (June 1970).
6. E. McMullin, Am. Philos. Quarterly (July 1881).
7. G. Gamow, Sci. Am. (March 1954).
8. J. V. Narlikar, New Scientist (2 July 1981).
9. F. Flam, Science (November 1991).
10. S. A. Gregory, and L. A. Thompson, Sci. Am. (March 1982).
11. A. Fisher, Popular Science (May 1991).
12. A. Chaikin, Omni (August 1991).
13. P.J.E. Peebles, Principles of Physical Cosmology (Princeton University Press, 1993).
14. D. Goldsmith, Discover (October 1992).
15. A. F. Davidsen, Science (15 January 1993).16. R. Jayawardhana, Astronomy (June 1993).
17. W. Freedman, Sci. Am. (November 1992).
18. J. R. Gott III, J. E. Gunn, D. N. Schramm and B. M. Tinsley, Sci. Am. (March 1976).
19. G. Abell, D. Morrison and S. Wolfe, Realm of the Universe (Saunders College Publishing, Philadelphia, 1988).
20. S. Gilkis, P. M. Lubin, S. S. Meyer, and R. F. Silverberg, Sci. Am. (January 1990).
21. D. Hegyi, "Interstellar Medium" in Encyclopedia of Physics, 2nd ed. (VCH Publishers, NY, 991).
22. J. Silk, The Big Bang (W. H. Freeman, NY, 1989).
23. S. van der Bergh and J. Hesser, Sci. Am. (January 1993).
24. W. C. Mitchell, The Cult of the Big Bang (Cosmic Sense Books, NV, 1995).
25. J. Boslough, Masters of Time (Addison-Wesley, Reading, MA, 1992).
26. D. Sciama, "Cosmology Before and After Quasars" in Cosmology +1 (W. H. Freeman, NY,1977).
27. H. Friedman, The Amazing Universe (The National Geographic Society, Washington, DC,1985).
28. S. G. Brush, Sci. Am. (August 1992).
29. S. Weinberg, The First Three Minutes (Basic Books, NY, 1977).
30. R. V. Coleman, "Whiskers" in Encyclopedia of Physics, 2nd ed. (VCH Publishers, NY, 1991).
31. J. Kanipe, Astronomy (April 1992).
32. H. C. Arp, G. Burbridge, J. V. Narlikar, N. C. Wickramasinghe, Nature (30 August 1990).
33. P. Yam, Sci. Am. (October 1990).
34. "Before There Was Earth, There Was Lightning" in Discover (July 1993).
35. J. D. Barrow and J. Silk, Sci. Am. (April 1980).
36. D. N. Schramm, and G. Steigman, Sci. Am. (June 1988).
37. R. Cowen, Science News (19 October 1991).
38. S. Bowyer, Sci. Am. (August 1994).
39. A. Gibbons, Sci. Am. (January 1992).
40. M. Bartusiak, Discover (August 1992).
41. J. A. Frieman, and B.-A. Gradwohl, Science (4 June 1993).
42. M. Schmidt, and F. Bello, "The Evolution of Quasars" in Cosmology + 1 (W. H. Freeman, NY, 1977).
43. C. D. Dermer, and R. Schlickeiser, Science (18 September 1992).
44. H. C. Arp, "Fitting Theory to Observation From Stars to Cosmology" in Progress in New Cosmologies: Beyond the Big Bang (Plenum Press, NY, 1993).
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-------------------------------------

Im pretty sure that leaves you 0 and 3 there mate
once you get tired of being so sure of Wikipedia and making unnecessarily aggressive statements based on such paper thin support you might find people to be a lot more engaging and accepting of whatever it is you might have to say
meanwhile a little humble pie would do you good
The big bang got the background radiation between 100 and 1000% wrong as noted and cited in the previous published work

Nanoose
12-22-2009, 09:19 PM
I thought recent work disputed these previous understandings (rather dated sources).

Boston
12-22-2009, 09:37 PM
there are many sound elements of physics that have stood many more than just a few short years

actually if anything I think the questions have gotten more complex and the theory finds itself on even thinner ice
although thats not to suggest its not the best we have at the present time, its just there is a lot of writing on the wall

there is some fundamental misunderstandings within the theory
time for instance
the universe appears to be older by far than what the Bang predicts
little things like that and the rising incongruities found in the background radiation/energy density and many more
in the end as time wears on
the theory weakens rather than finds itself on more solid ground
its an interesting situation
the only theory we have
and its not all that good
kinda a nice test of an open mind if you ask me

cheers
B

skuthorp
12-22-2009, 10:53 PM
I have a nephew who'se hobby is this sort of thing. For the rest of us it requires faith as the 'answer' is as unintelligible as background required and often the question.

Nanoose
12-22-2009, 11:17 PM
...the theory finds itself on even thinner ice

the universe appears to be older by far than what the Bang predicts


How much older?
NASA disagrees with you:
http://map.gsfc.nasa.gov/universe/bb_concepts.html

Keith Wilson
12-22-2009, 11:23 PM
Apparently you didn't see post #46, which references several sites on the subject, including the University of Chicago and Lawrence Berkeley Labs. The latter are the web pages of the group headed by George Smoot, the fellow who won the 2006 Nobel Prize in physics for his work on CMBG anisotropy. ) They have further links if you're interested.

A long list of footnotes does not a good article make. Mr Hasselhurst (his web pages are here) (http://www.spaceandmotion.com/) seems just a bit - um - ambitious, covering a surprisingly large range of subjects, with as much philosophy as science. Has he published anything in a peer-reviewed scientific journal? From the autobiography on his web site , he does not appear to have any training in advanced physics. He seems an interesting guy, but I think on astrophysics and cosmology one would do better to trust George Smoot. (http://www.lbl.gov/Publications/Nobel/)

Nanoose
12-22-2009, 11:43 PM
Keith - "you" who? me? or boston?

Keith Wilson
12-23-2009, 12:16 AM
Sorry - Boston, not you. He references an Australian fellow named Geoff Haselhurst, who seems a bit out of the mainstream of astrophysics.

skuthorp
12-23-2009, 12:36 AM
A bit! http://open-site.org/profiles/haselhurst.html

Glen Longino
12-23-2009, 12:44 AM
The Benny Hinn of physics and his balmy girlfriend!

Popeye
12-23-2009, 07:56 AM
.. feel free to present a better theory for the beginning of the universe.

how can i do that ?

Popeye
12-23-2009, 08:31 AM
The Benny Hinn of physics and his balmy girlfriend!

who is w c mitchell? , this may be a fair question , since he is the one who wrote the article , not haselhurst

Glen Longino
12-23-2009, 09:08 AM
My response was to the link posted by skuthorpe.

Popeye
12-23-2009, 09:32 AM
.. who followed keith's lead in providing us with yet another misnomer

0 for 3 is about right

Keith Wilson
12-23-2009, 10:24 AM
The link to Haselhurst was the only link Boston provided. The original article is here (http://open-site.org/Science/Physics/Cosmology_Problems_Big_Bang), on "Open Site, the Free Internet Encyclopedia"; an odd choice, from someone who ridicules Wikipedia. It appears to have been edited and posted by Mr. Haselhurst, from the writing of William C Mitchell. Mr. Mitchell is the author of two books, (http://www.amazon.com/William-C.-Mitchell/e/B001K93P20/ref=ntt_dp_epwbk_0) Goodbye Big Bang, Hello Reality (Cosmic Sense Books, 2002) and The Cult of the Big Bang; Was There a Bang? (Cosmic Sense Books, 1995). Cosmic Sense Books (http://www.books-by-isbn.com/0-9643188/) has not published anything other then these two works , which indicates that Mr. Mitchell's work is self-published. In a fair amount of searching, I have not been able to find out anything about Mr. Mitchell's background or credentials, which is curious for an author of books about cosmology. His books are referenced in a footnote in the Wikipedia article on "Non-Standard Cosmology". (http://en.wikipedia.org/wiki/Non-standard_cosmology) Right or wrong, this appears to be a very long way from mainstream science.

I am not qualified to discuss cosmology on any level but the most elementary; I have neither the background not anywhere near enough math. I doubt anyone here except Ingo does. However, I think I can say two things with complete confidence - and Ingo, please correct me if I'm wrong:
- The big bang is accepted as true by the vast majority of people working in the field - as close to fact as a scientific theory about events some 14 billion years ago is likely to get. Like any scientific theory, it's subject to revision as we learn more.
- The observed CMBR, both the spectrum and the anisotropy, is considered by the vast majority of people working in the field as some of the best evidence supporting the big bang.

Popeye
12-23-2009, 10:32 AM
cmbr could be from anywhere , the fact that you can observe it is not evidence of where it originates from

in cosmology , 'flatness' and bbt are not compatible

Popeye
12-23-2009, 10:37 AM
- The big bang is accepted as true by the vast majority of people working in the field - as close to fact as a scientific theory about events some 14 billion years ago is likely to get.

this is your arrogance , not the scientific community , please keep them separate


Like any scientific theory, it's subject to revision as we learn more..

it's also subject to being completely wrong :rolleyes:

Popeye
12-23-2009, 10:53 AM
.. this appears to be a very long way from mainstream science..

linky linky (http://photoman.bizland.com/bbnh/p7.htm)
:rolleyes::D

Popeye
12-23-2009, 10:57 AM
.., this appears to be a very long way from mainstream science.

halton arp (http://en.wikipedia.org/wiki/Halton_Arp)

Keith Wilson
12-23-2009, 11:02 AM
CMBR is not "flat". George Smoot (http://en.wikipedia.org/wiki/George_Smoot) won a Nobel prize for his work on CMBR non-uniformity Look here. (http://en.wikipedia.org/wiki/COBE) Here's a map.

http://upload.wikimedia.org/wikipedia/commons/1/1d/COBE_cmb_fluctuations.gif

You may not like the big bang, but there is currently no other idea which comes close to adequately explaining CMBR.

Sure, the big bang could be completely wrong; somebody may discover something tomorrow which overturns it, but they haven't yet. It is indeed thought to be true by the vast majority of people working in the field (not all). All I am saying is that the big bang is generally accepted as mainstream science. It could be wrong, but that's a fact

Personally, I don't much care one way or another about the origin of the universe. I may get passionate about discussions of evolution; not about this. It's interesting to stumble onto dedicated "big bang skeptics", some of whom have all the standard traits of fringe science. Others, like Halton Arp, look quite respectable. I didn't know was such a thing, but then I don't follow cosmology. I'm not surprised.

Popeye
12-23-2009, 11:51 AM
You may not like the big bang, but there is currently no other idea which comes close to adequately explaining CMBR.'like' the big bang ? well .. oh never mind .. :D

um , keith , last i checked , anytime you get photons and magnetic fields together , you are very likely to get radiation :rolleyes::rolleyes:

the universe seems abundant in both photons and em fields of all sorts , cmbr may or may not be a remnant of some past cosmological event and is therefore not evidence of a bb , you may as well say starlight is 'evidence' of .. ? ..

there are well placed theories to deal with the presence of the universe , a 'primordial beginning' may well hold no meaning for what we are discussing , in the vast configuration of things what do you suppose you are missing ?

Peerie Maa
12-23-2009, 11:56 AM
Has any one noticed that Popeye is starting to sound the way SamF does when Sam is debating evolution?:confused:

Jus saying.;):D

Popeye
12-23-2009, 11:58 AM
.. the big bang could be completely wrong; somebody may discover something tomorrow which overturns it, but they haven't yet.


yes , they have

Keith Wilson
12-23-2009, 11:59 AM
You'll have to argue with with someone else, popeye. As I said, I don't know enough to discuss cosmology on other than the most basic level, and I suspect you don't either. Most of the people working in the field think the big bang is correct, and that CMBR is good evidence of that. I'll go with that for now until somebody comes up with a better idea.

Popeye
12-23-2009, 12:00 PM
Has any one noticed that Popeye is starting to sound the way SamF does when Sam is debating evolution?.

i've notice big bangers have a rather peculiar cultist quality to them , and any dissenting heretics need to be dropped into a black hole

so much for the scientific view we all cherish so much

Kaa
12-23-2009, 12:02 PM
Has any one noticed that Popeye is starting to sound the way SamF does when Sam is debating evolution?:confused:

Well, kinda :D SamF at least bothers to twist and turn and misuse logic and lay traps... Popeye goes straight to obscure obfuscations and stays there.

Kaa

Popeye
12-23-2009, 12:05 PM
.. Popeye goes straight to obscure obfuscations and stays there.if a theory has problems and major logical gaps , one might ..

a > abandon the theory

b> fix the theory

c> after following 'b' for half a century , stand back from the theory and wonder why all those if ands buts , not always , sometimes and 'doesn't work whens' are starting to look like a frankenstein

jus say'n

Keith Wilson
12-23-2009, 12:41 PM
If a theory has problems and major logical gaps . . .If. The vast majority of people in that field disagree with you, and my understanding is that recent satellite CMBR data supports the theory quite strongly. They could all be wrong; reality does not respect our opinions, but I know which way I'd bet.

Popeye
12-23-2009, 12:50 PM
If. The vast majority of people in that field disagree with you... They could all be wrong; reality does not respect our opinions, but I know which way I'd bet.but there are problems with bbt , when issues like the 'singularity' problem defies the theoretical , it pales by comparison with the latest findings! , hubble space telescope data included

dude, the universe is infinite , where's your primordial egg at ? :confused:

Peerie Maa
12-23-2009, 01:00 PM
You need to start backing up your opinions with some up-to-date peer reviewed references, otherwise you will sound like SamF with his "fairy stories" rebuttal of evolution.

Popeye
12-23-2009, 01:13 PM
You need to start backing up your opinions with some up-to-date peer reviewed references

peewee , try the nasa information nanner provided :rolleyes:

Peerie Maa
12-23-2009, 01:32 PM
peewee , try the nasa information nanner provided :rolleyes:

You mean this statement?

The simplest version of the inflationary theory, an extension of the Big Bang theory, predicts that the density of the universe is very close to the critical density, and that the geometry of the universe is flat, like a sheet of paper. That is the result confirmed by the WMAP science.
Which tells me that the authors of that page do agree that the Big Bang is confirmed by another dollop of evidence. Yes?

Popeye
12-23-2009, 01:38 PM
.. the authors of that page do agree that the Big Bang is confirmed by another dollop of evidence. Yes? no , this is the 'flatness problem (http://en.wikipedia.org/wiki/Flatness_problem)' :rolleyes::confused:

say , why do they call the 'flatness problem'.. a problem , i'm wondering ? :D:rolleyes:

Popeye
12-23-2009, 01:45 PM
As I said, I don't know enough to discuss cosmology on other than the most basic level, and I suspect you don't either..excuse me .. you may speak for yourself and your enginerd friends

but i seem to be one of the few bilge creatures able to actually read and understand the science and scientific literature

good grief but you are a nincompoop some days :rolleyes:

Peerie Maa
12-23-2009, 01:52 PM
I'll try one more time, then you'r on your own.:p

an extension of the Big Bang theory,Step 1.

predicts that the geometry of the universe is flat, like a sheet of paper.step 2.

That is the result confirmed by the WMAP science. we arrive.:D
A slight change in order:
WMAP science confirms that the universe is flat.
This is a prediction of the Big Bang theory.
When observation confirms theory, said theory is strengthened.
Geddit?

Popeye
12-23-2009, 02:03 PM
WMAP science confirms that the universe is flat.
This is a prediction of the Big Bang theory.nope , the flatness problem is completely at odds with the big bang theory

'inflation' is later invented as an add-on to the bbt to help explain the problem .. thus the flatness problem persists :rolleyes::rolleyes:

wiki..

Although inflationary theory is regarded as having had much success, and the evidence for it as compelling, it is not universally accepted: cosmologists recognise that there are still gaps in the theory and are open to the possibility that future observations will disprove it. In particular, in the absence of any firm evidence for what the field driving inflation should be, many different versions of the theory have been proposed.

For these reasons work is still being done on alternative solutions to the flatness problem.

Popeye
12-23-2009, 02:23 PM
CMBR is not "flat". Here's a map.

that map is wrong :eek:

some days you guys aren't too swift :rolleyes::D

Keith Wilson
12-23-2009, 02:50 PM
but i seem to be one of the few bilge creatures able to actually read and understand the science and scientific literatureIndeed? Perhaps you should also learn how to write intelligible grammatical English, and to make an attempt to explain your thoughts instead of writing telegrams. While you've certainly been free with the insults today, so far you have shown no evidence of having anything worthwhile, or even coherent to say on the subject.

'Bye.

Popeye
12-23-2009, 02:55 PM
This is 100% dead false.

toodles :rolleyes:

Peerie Maa
12-23-2009, 02:59 PM
toodles :rolleyes:

PROOF

PROOF at last

Popeye IS SamF.

Told ya so :p:D:D

Popeye
12-23-2009, 03:08 PM
hiya peewee , still working on why a problem is called a problem .. tough one eh

ingo
12-23-2009, 03:20 PM
I am not qualified to discuss cosmology on any level but the most elementary; I have neither the background not anywhere near enough math. I doubt anyone here except Ingo does. However, I think I can say two things with complete confidence - and Ingo, please correct me if I'm wrong:
- The big bang is accepted as true by the vast majority of people working in the field - as close to fact as a scientific theory about events some 14 billion years ago is likely to get. Like any scientific theory, it's subject to revision as we learn more.
- The observed CMBR, both the spectrum and the anisotropy, is considered by the vast majority of people working in the field as some of the best evidence supporting the big bang.

To correct you: The universum is 13.73 +/- 0.12 billion years old ;-) As far as we know. This was one result of the WMAP mission (http://en.wikipedia.org/wiki/Wilkinson_Microwave_Anisotropy_Probe) This is accepted by thevery vast majority of astrophysicists. As allways, there are some who do not agree and prefer other models. This is fine since permanent critical diskussion is the best way to get the theory better.
There are no other theories that come even close in describing the measurements.

pefjr
12-23-2009, 03:24 PM
Wish I could help you boys out but I am fresh out of answers at the moment. Other than, I think the universe will be a little bigger tomorrow.

Peerie Maa
12-23-2009, 03:27 PM
hiya peewee , still working on why a problem is called a problem .. tough one eh

Not at all,
I have proven my thesis.:D

ingo
12-23-2009, 03:38 PM
Popeye, you may be a nice guy and we have christmas and so on. But it is just in vain to discuss this topic with someone who is not educated to do so. I can try to explain something but if you want a discussion you have to prove your ability to do so.

Big Bang Theory is the standard model since it explains more than any other model and there are no relevant contradictions. This does not say it explains everything (there is no model what has happend before Planck-time since this would need a total different physics), but it explains the effects that can be measured.

If you are looking for the idea of a new physics, read "A Different Universe: Reinventing Physics from the Bottom Down" by Robert Laughlin. He got the nobel price in physics in 1998 for the fractional quantum Hall effect. This is really an enlightment and readable for "normal" people with a medium scientific background.

Glen Longino
12-23-2009, 07:34 PM
Yeah, Popeye, you ignert spinach-guzzlin', Sam F lookalike !!!:D:)

Captain Blight
12-23-2009, 11:52 PM
It's pretty much impossible for human beings to visualize curved 3-dimensional space. What if they think of oranges or volleyballs or planets? Aren't those objects curved in all 3 dimensions?

Captain Blight
12-24-2009, 12:13 AM
With an appropriate theory everything is possible ;-)

Indeed the "standard big bang theory" says that all 4 basic forces were one.

At least directly after the Planck-time (5*10^-44 seconds). There can be made no predictions for the "time" between 0 and Planck-time since time itself did not exist as a continuum.

The first force that separated directly after Planck-time was gravity.

At 10^-35 seconds the strong nuclear force separated.

At 10^-12 seconds the weak nuclear force separated.

What was left was the electromagnetic force.

And please - do not talk about "before big bang" or "outside the universe" as long as you refer to our dimensions. Our spacetime does only exist in our universe. Or - to be more correct - our universe is defined as our spacetime.

Thank you for posting this, I missed it earlier and it's worded very nicely. Brings up a couple more big questions (for me) perhaps more cosmological than cosmographical-- I guess I'm wondering if time, even in durations as infinitesimal as Planck-time, can be considered as a force the same way gravity or magnetism can be. Even looking at something as basic as horsepower/torque, time is always involved... is it or can it be something more tangible than an arbitrary scaling function?

Forgive me if this is actually basic stuff for the conversation, but cosmology is a new field for my reading these days.

That is all, please resume, thanks a lot, nothing to see here, move along....

Popeye
12-24-2009, 08:03 AM
This is accepted by thevery vast majority of astrophysicists..... who use the bbt to describe how the universe began , but not all physicists agree the universe has a 'beginning' in the human cultural sense of the word


As allways, there are some who do not agree and prefer other models. ...

..to describe the universe , and some of those rigourous models use infinite , 'flat' space , and therefore contain no .. ' beginning' postulate :rolleyes:


This is fine since permanent critical diskussion is the best way to get the theory better. what theory , do you mean the bbt ? .. hold on a sec ..:rolleyes: .. what if .. we don't use the bbt , then what else do we use ? i think you like avoiding this distinct possibility .. why is that ?


There are no other theories that come even close in describing the measurements.bs .. , maxwells equations decribe uwave radiation from conventional sources perfectly

Popeye
12-24-2009, 08:15 AM
But it is just in vain to discuss this topic with someone who is not educated to do so.

i agree , you seem to slip out of the most basic questions , which leads me to think you have some sort of horse in this race , why can't you discuss anything but bbt ? i guess you don't have the education required


I can try to explain something but if you want a discussion you have to prove your ability to do so.

don't think so , on an internet forum ? , where bs is rampant :D , and you sir have no more inkling about the beginnings of the universe than anyone else here , simply regurgitating first year physics is a trite discussion which anyone may do , you included :rolleyes:


Big Bang Theory is the standard model since it explains more than any other model and there are no relevant contradictions.

with statements like this , it becomes abundantly clear you have no idea about the latest thinking on this issue , bbt is full of holes ,a lways has been , the evidence is because it needs to be revamped so often and in so many strange ways makes bbt pretty ugly

to say bbt has 'no relevant contradictions' .. :eek: .. is simply , sorry.. but .. stupid :rolleyes:


This does not say it explains everything (there is no model what has happend before Planck-time since this would need a total different physics), but it explains the effects that can be measured.

illustrates the point i am making , you are assuming there must be concepts like ' before plank time' to deal with , you are putting the horse before the cart , the effects measured can also be explained by classical physics , duh


If you are looking for the idea of a new physics, read "A Different Universe: Reinventing Physics from the Bottom Down" by Robert Laughlin. He got the nobel price in physics in 1998 for the fractional quantum Hall effect. This is really an enlightment and readable for "normal" people with a medium scientific background.

you are abnormal ? ok then

Popeye
12-24-2009, 08:18 AM
I have proven my thesis.

nice , but i'm giving both you an ingo an 'f'

there's a clue for ya ..

Popeye
12-24-2009, 08:22 AM
And please - do not talk about "before big bang" or "outside the universe" as long as you refer to our dimensions. Our spacetime does only exist in our universe. Or - to be more correct - our universe is defined as our spacetime.wizardy

here's the school of thought ingo subscribes to , once we reach our own preset boundaries , then we pull out the magic ..

Some cosmologists agreed with Dicke that the flatness problem was a serious one, in need of a fundamental reason for the closeness of the density to criticality. But there was also a school of thought which denied that there was a problem to solve, arguing instead that since the universe must have some density it may as well have one close to ρcrit as far from it, and that speculating on a reason for any particular value was "beyond the domain of science". Enough cosmologists saw the problem as a real one, however, for various solutions to be proposed.

good grief

Popeye
12-24-2009, 09:36 AM
"..unfortunately, i cannot start the film at zero time and infinite temperature.."

~ steven weinberg

Popeye
12-24-2009, 09:40 AM
" ..it seems to be a good principle that the prediction of a singularity by a physical theory indicates that the theory has broken down.. "

~ stephen hawking
~ g f r ellis

Popeye
12-24-2009, 09:51 AM
".. for us who are convinced physicists, the distinction between past, present, and future is only an illusion, however persistent.."

~ albert einstein

pefjr
12-24-2009, 09:56 AM
See what a dog fight you have caused Nanny. Do not ask for help in the bilge!!!!!

Popeye
12-24-2009, 10:11 AM
" ..so far the measurements of the spectrum have been beautifully consistent with the predictions of inflation, although it must be admitted that nonuniformities created by cosmic strings are also consistent with the observations.."

".. it should be stressed that inflation is really a paradigm and not a theory.."

a guth

Popeye
12-24-2009, 10:13 AM
" .. all these models seem so awkward, and so finely tuned.."

~ mark wise , cosmologist , california institute of technology.

Popeye
12-24-2009, 10:16 AM
"..you're trying to explain away certain features of the universe that seem fine-tuned—like its homogeneity, or its flatness , but you do it by a mechanism that itself requires fine tuning. and that concern, which was there from the beginning, remains now."

~ paul steinhardt

Popeye
12-24-2009, 10:18 AM
"..consider where we started from: we were going to explain everything, now we explain almost nothing.."

~ paul steinhardt

Popeye
12-24-2009, 10:21 AM
" ..inflation is not yet a theory, it is more of a nice idea at this point.."

~ andreas albrecht

Popeye
12-24-2009, 10:34 AM
" .. big bang theory .. explains more than any other model and there are no relevant contradictions.. "

~ ingo , nincompoop cum latter

Popeye
12-24-2009, 10:35 AM
" .. the big bang is accepted as true by the vast majority of people working in the field .. "

~ k wilson et al , perfessuer emeritus , institute of higher bilge at minnesota

Nanoose
12-24-2009, 11:06 AM
So, Pops....help me, here.
Red shift seems to indicate a flat universe (right?).
And flat means no beginning (right?).
Why can flat not mean there was some beginning?
If the flatness tells us no beginning, then we have an eternal, infinite universe, right?
If that is the case, on what basis do we date the universe at approx. 14 billion years old?
Sincere questions from one who really does like to understand and learn.
Many thanks.
Deb

Peerie Maa
12-24-2009, 11:12 AM
Deb,
Look at Ingo's posts in this thread. It would seem that this is Ingo's field.

Nanoose
12-24-2009, 11:13 AM
Yes, I will reread his posts...but I'm wondering what Pops is thinking here too. I just need it in really plain english!! :o

Popeye
12-24-2009, 11:14 AM
ingo is out standing in his field

right now

pefjr
12-24-2009, 11:15 AM
" when you are traveling through the universe and come to a fork in a worm hole , take it"
Yogi Berra and B Forrester

Peerie Maa
12-24-2009, 11:16 AM
Yes, I will reread his posts...but I'm wondering what Pops is thinking here too. I just need it in really plain english!! :o

That is something Pops is not usually known for;)

Popeye
12-24-2009, 11:18 AM
I'm wondering what Pops is thinking here too. I just need it in really plain english!!

big bang theory .. wrong-a-mundo

we need a new theory to explain primarily the 'why' of the universe , iow , it's presence

there are one or two really good theories just out , not big bang stuff ,

m - stuff

Nanoose
12-24-2009, 11:22 AM
we need a new theory to explain primarily the 'why' of the universe , iow , it's presence



Generally, science isn't about the 'why', i.e. it's not a question science can answer.

But, as you are saying bb has too many problems, there must be alternatives on the table. I'm just not aware of what they are, and wondering what you are aware of.

Also, if you could help with my questions in #163, I'd be most grateful. Thx.

Popeye
12-24-2009, 11:26 AM
Red shift seems to indicate a flat universe (right?). some awfully good cosmologists suggest 'red shift' is nothing more than 'tired' photons ..

the problem is , the deeper we peer at the horizon (hubble) , the more galaxies we find , we are finding more universe , not less , and it's moving faster , not slower

the whole idea of an exploding 'egg' suggests there will be a boundary which we should be able to see , but it ain't there

Kaa
12-24-2009, 11:27 AM
So, Pops....help me, here.

Err... ummm... :D


Red shift seems to indicate a flat universe (right?).

I think the red shift indicates an expanding universe, not necessarily a flat one.


And flat means no beginning (right?).

"Spatially flat" means no natural boundaries, aka infinite in size. There is no implication that flat spaces have no beginning.

Kaa

Nanoose
12-24-2009, 11:28 AM
thx, kaa

but I am wondering, what theories are being brought to the table by those who say bb isn't accurate to account for the data....

Popeye
12-24-2009, 11:30 AM
flat means no beginning (right?).

yup , that's what me and s hawking are saying , time did not 'begin'

Popeye
12-24-2009, 11:33 AM
Why can flat not mean there was some beginning? sure it can , simply means there may be more than one

the bb crowd get stuck on the 'singularity' problem , hawking suggests a beginning also , just no singularity

Nanoose
12-24-2009, 11:34 AM
How can something be infinite in size and still have a beginning. The beginning indicates a time factor and therefore finite. I'm having trouble seeing how those 2 can go together. Can you think of some kind of example/picture to help me out?

Peerie Maa
12-24-2009, 11:36 AM
Deb, Ingo pointed out that there was a different sort of time between the BB and Plank-time.

As I posted earlier, we do not know anything about the time between zero and Planck-time since our concept of time does not fit there.
So we do not yet have the ability to understand the very beginning.

Popeye
12-24-2009, 11:37 AM
If the flatness tells us no beginning, then we have an eternal, infinite universe, right?

' flatness' suggests infinite space , true

but time did not begin and may not be flat , think for a second about the four dimensions we are all so well versed in

Popeye
12-24-2009, 11:38 AM
.. we do not yet have the ability to understand the very beginning.

tripe

Kaa
12-24-2009, 11:39 AM
thx, kaa

but I am wondering, what theories are being brought to the table by those who say bb isn't accurate to account for the data....

I wouldn't call them "theories", but I think they are mostly described in Genesis... :-)

Kaa

Popeye
12-24-2009, 11:42 AM
on what basis do we date the universe at approx. 14 billion years old?

einstein was also able to calculate the 'diameter' of the universe based on a s-t curvature tensor

bbt tries to run the movie backwards to a single point in time based on a homogeneity , see the problem ?

Popeye
12-24-2009, 11:43 AM
The beginning indicates a time factor and therefore finite.

nope

Kaa
12-24-2009, 11:44 AM
How can something be infinite in size and still have a beginning. The beginning indicates a time factor and therefore finite. I'm having trouble seeing how those 2 can go together. Can you think of some kind of example/picture to help me out?

Geometrically, think of a ray. It has both a beginning and an infinite length.

Physically, consider that (according to our contemporary understanding, yadda yadda) the speed of light is the maximum speed possible. If the "boundaries" of the universe move outwards at the speed of light, you will never reach them -- you can move forever and cover an infinite distance.

Kaa

Popeye
12-24-2009, 11:48 AM
Can you think of some kind of example/picture to help me out?will post the model , soon as i find a good site ( it was actually carried in the mainstream media for a short while)

apparently the universe has an 'inside and an 'ouside' and they get 'inverted' once and a while , therefore a beginning mode , continuing time and infinite space model all become compatible ideas

SamSam
12-24-2009, 03:21 PM
.. this appears to be a very long way from mainstream science.. You repost that above and then your two links. I can't tell if you post these names because you believe these guys are mainstream or a very long way from mainstream.


linky linky (http://photoman.bizland.com/bbnh/p7.htm)
:rolleyes::D


http://en.wikipedia.org/wiki/Wikipedia:Articles_for_deletion/Eric_Lerner


As the debates on the talk page show, there are very few independent reliable sources primarily about Lerner. Kudos to SA for stepping back and checking his perspective - "we need to rebut this kook" is a poor reason for having an article on a barely-notable person who runs a non-notable company and has received a non-notable award from a maybe-but-likely-not-very notable group.
Since Wikipedia is not paper, we could include marginally notable biographies, but I'm not even sure Eric Lerner is marginally notable. We don't want articles on all the people that have their own (unsuccessful) company, or that wrote one book that caused some discussion several years ago, or that won some award once. Lerner at least did all of these things, but still, he's just not very important. (Based on secondary sources. Of course, if you personally believe that he will achieve economical fusion or that plasma cosmology will eventually surplant the Big Bang theory, I can understand your frustration.)
halton arp (http://en.wikipedia.org/wiki/Halton_Arp)

http://en.wikipedia.org/wiki/Talk:Halton_Arp



Previous renditions of this entry gave the misleading impression that Arp's QSO theory still has some acceptance in the science community. I have tried to rewrite the entry to be as nice to Arp as possible and even present his position in a good lightwhile stating that current scientific evidence overwhelmingly disfavors his position..

Nanoose
12-24-2009, 04:38 PM
but time did not begin

Time is sequential - there is a 'before' and an 'after'; and in order to be so, must have a 'start'. It cannot be otherwise. You cannot have an actual infinite regress.

johnw
12-24-2009, 05:51 PM
Time is sequential - there is a 'before' and an 'after'; and in order to be so, must have a 'start'. It cannot be otherwise. You cannot have an actual infinite regress.
I'm not sure why. If length can be infinite in both directions, why not all four dimensions we perceive?

Keith Wilson
12-24-2009, 05:56 PM
Time is sequential - there is a 'before' and an 'after'; and in order to be so, must have a 'start'. It cannot be otherwise. You cannot have an actual infinite regress.I'd say we don't know enough about time to have the vaguest clue whether this is true or not.