Can Space be created within space?
in [Physics]
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From: nuny on 5 Aug 2010 04:33 On Aug 4, 5:18 pm, Huang <huangxienc...(a)yahoo.com> wrote: > On Aug 4, 1:45 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Aug 4, 1:26 pm, Huang <huangxienc...(a)yahoo.com> wrote: > > > > On Aug 4, 9:20 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Aug 3, 4:02 pm, Huang <huangxienc...(a)yahoo.com> wrote: > > > > > > On Aug 3, 3:25 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Aug 3, 2:49 pm, Huang <huangxienc...(a)yahoo.com> wrote: > > > > > > > > On Aug 3, 10:26 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > On Aug 2, 6:21 pm, Huang <huangxienc...(a)yahoo.com> wrote: > > > > > > > > > > > > > > Sam, I did not say anything about centerless universe. If you can have > > > > > > > > > > > > > centerless expansion, then you can also have centerless contraction. > > > > > > > > > > > > > > Just as the universe can be regarded as expanding "without a center", > > > > > > > > > > > > > so too it can be modelled as a contraction "without a center". > > > > > > > > > > > > > That's correct. Observation show that space is expanding.- Hide quoted text - > > > > > > > > > > > > > - Show quoted text - > > > > > > > > > > > > But I think that Hubble's interpretation of redshift was a bit off. > > > > > > > > > > > Hubble gives only two concievable explanations: > > > > > > > > > > > > [a] Everything is flying away from us, placing us in the center of a > > > > > > > > > > > bunch of stuff which is moving outwards, or > > > > > > > > > > > [b] Space is expanding and is centerless. > > > > > > > > > > > > I think that his options were incomplete. I think that either: > > > > > > > > > > > > [a] Space is expanding and is centerless. > > > > > > > > > > > [b] We are contracting away from space and it is centerless. > > > > > > > > > > > > I think that both of these are valid possibilities, and that they > > > > > > > > > > > should be equivalent under Equivalence Principle. > > > > > > > > > > > Please. Stop with the gobbledygook. > > > > > > > > > > The Principle of Relativity does NOT mean "everything is relative". > > > > > > > > > > The Principle of Equivalence does NOT mean "opposite things are > > > > > > > > > > equivalent." > > > > > > > > > > > You can babble if you want. I just don't recommend that you attach > > > > > > > > > > buzz phrases from pulp physics to the babbling. It will only put folks > > > > > > > > > > off.- Hide quoted text - > > > > > > > > > > So, the only time we can apply the Equivalence Principle is when we > > > > > > > > > are looking at rectilinear motion. Cant apply it to anything else > > > > > > > > > except trains and rockets. > > > > > > > > > Nor did I say that. > > > > > > > > You, the fuzzy logic champion, seem to veer quite dramatically from > > > > > > > > Black to White. > > > > > > > > "Well, if it means more than trains and rockets, then I can say it > > > > > > > > means whatever I want, can't I?" > > > > > > > > > > Ahem - > > > > > > > > > > Space is a "physical thing". And whenever two physical things are in > > > > > > > > > motion with respect to each other, relativity must apply. > > > > > > > > > No, sir. This again is gobbledygook. > > > > > > > > > > If one > > > > > > > > > region of space (which is a thing) appears to be in motion relative to > > > > > > > > > another, then I see no reason why these principles wouldnt apply.- Hide quoted text - > > > > > > > > > - Show quoted text -- Hide quoted text - > > > > > > > > > - Show quoted text - > > > > > > > > Surely you would concede that expansion of space qualifies as "motion" > > > > > > > of something. Something must be in motion, otherwise the concept of > > > > > > > expansion is just vacuous. > > > > > > > > If the universe were 1-dimensional, then it might be easier to see > > > > > > > that something must be in motion. > > > > > > > > Are we now arguing that something such as space can expand and that > > > > > > > there was no motion involved in this process ? Doesn't that seem a bit > > > > > > > contradictory ? > > > > > > > First of all, the principle of relativity does not apply to any old > > > > > > kind of motion. Nor does the principle of equivalence. > > > > > > Secondly, there IS a difference between something moving from one > > > > > > coordinate in space to another coordinate in space, and the metric of > > > > > > space itself changing. > > > > > > > Rather than muddling through with loose interpretations of terms that > > > > > > are in fact carefully defined and delineated, don't you think it would > > > > > > be beneficial if you actually learned some of the careful delineations > > > > > > and definitions? > > > > > > > Or is it more fun for you to just babble in free-association style, > > > > > > hoping that you can defend some loose connection between your thinking > > > > > > and what physics means by these things? > > > > > > > PD- Hide quoted text - > > > > > > > - Show quoted text - > > > > > > There's more than one way to skin the cat, and as some of those ways > > > > > are equivalent. Has to be. > > > > > > All Im suggesting is that there is a maximal segment of time allowable > > > > > by physics, and suggesting a way to estimate what it is. Age of > > > > > universe based on big bang, added to time we've got left until the big > > > > > crunch. > > > > > What's the rationale that there is even going to be a big crunch? > > > > Is your rationale the fact that you heard it on TV some time ago? > > > > > > That would yield a cosmic counterpart to Planck Time, the > > > > > maximal segment of time possible given contemporary physics.' > > > > > It's only a counterpart in the sense that you would arbitrarily pair a > > > > minimum with a maximum. > > > > But this is like pairing a virus with a blue whale and implying that > > > > they must be related. > > > > > > I would actually calculate the time left until the big crunch based on > > > > > a contracting spacetime, which I consider equivalent to an expanding > > > > > one. > > > > > > I dont really know where I might have muddled any definitions in that, > > > > > but your perfectly welcome to criticize anyhting I say because frankly > > > > > I have a certain amount of confidence that it's a worthwhile idea.. > > > > > Whether correct or not I do not know, but then again Im not the one > > > > > funding things such as SETI am I. > > > > > That's true, and so now I understand your gambit. > > > > You perceive a lot of the research that is being done (like SETI) to > > > > be pointless diddling exercises without real rationale or clear > > > > thought. If they had a rationale or clear thought behind them, you > > > > tell yourself, then you would understand and endorse the projects. But > > > > since you don't, then they must not have a well-considered > > > > justification. That being said, you figure that you are just as > > > > entitled to engage in a similar, pointless, diddling exercise without > > > > much in the way of a well-considered justification or clear rationale. > > > > And so you toss in your barely baked ideas, imagining that they must > > > > be at least as baked as some of the other things you've seen in the > > > > news. Perhaps you can get your slice of notoriety by tossing your > > > > barely baked contribution into the ring. > > > > > > Raises one eyebrow. > > > > > > ?.- Hide quoted text - > > > > > - Show quoted text -- Hide quoted text - > > > > > - Show quoted text - > > > > I was only joking about SETI. Personally I tend to believe that indeed > > > we are not the only living things in this universe. It's not very > > > reasonable to think that we are alone. > > > > But the justification for a big crunch would be the idea that we are > > > contracting away form space, causing redshift. Certainly we can only > > > contract just so far until we are no more. > > > Sorry, but that has nothing to do with the big crunch. In the big > > crunch, objects in the universe are *approaching* each other, and > > their radiation is blue-shifted. > > > As I mentioned earlier, it helps to know what terms used in physics > > actually mean, rather than just trying to "intuit" what they mean and > > following implications of what you THINK they mean. But to do that > > requires a little reading, which is apparently more effort than you > > are willing to put out. > > OK - so the term "Big Crunch" has already been coined many years ago > to describe the death of the universe based on bgi bang cosmology, yes > yes I concede, I stole a name that some else had already reserved for > this other well known process which was described decades ago. > > For that you have my apology. > > However, the concept of a crunch of some kind is appropriate and so > maybe I should distinguish my big crunch from pre-existing big > crunches. So - the process I described, lets call it the "Big Smoosh". > > Would that appease the powers that be ? I'll point out here that there is serious speculation that the anisotropies seen in the CMBR can be attributed to anisotropic expansion in different parts of the Universe (at different times as well), and that some parts may even be contracting. http://www.google.com/search?q="anisotropic+expansion"+universe I can buy the anisotropic expansion part because AFAIK there's no obvious mechanism to tie together the rates of expansion of two widely separated parts of the Universe. As for the contraction part, not so much to my taste. One patch may be expanding slower than the patch next to it and might *seem* to be contracting by comparison, but that's about as far as I'm willing to go. Locally, space would still appear to be expanding. It Seems To Me, anyway. I could be wrong. Mark L. Fergerson
From: Huang on 5 Aug 2010 18:37 On Aug 5, 3:33 am, "n...(a)bid.nes" <alien8...(a)gmail.com> wrote: > On Aug 4, 5:18 pm, Huang <huangxienc...(a)yahoo.com> wrote: > > > > > > > On Aug 4, 1:45 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Aug 4, 1:26 pm, Huang <huangxienc...(a)yahoo.com> wrote: > > > > > On Aug 4, 9:20 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > On Aug 3, 4:02 pm, Huang <huangxienc...(a)yahoo.com> wrote: > > > > > > > On Aug 3, 3:25 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > On Aug 3, 2:49 pm, Huang <huangxienc...(a)yahoo.com> wrote: > > > > > > > > > On Aug 3, 10:26 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > On Aug 2, 6:21 pm, Huang <huangxienc...(a)yahoo.com> wrote: > > > > > > > > > > > > > > > Sam, I did not say anything about centerless universe. If you can have > > > > > > > > > > > > > > centerless expansion, then you can also have centerless contraction. > > > > > > > > > > > > > > > Just as the universe can be regarded as expanding "without a center", > > > > > > > > > > > > > > so too it can be modelled as a contraction "without a center". > > > > > > > > > > > > > > That's correct. Observation show that space is expanding.- Hide quoted text - > > > > > > > > > > > > > > - Show quoted text - > > > > > > > > > > > > > But I think that Hubble's interpretation of redshift was a bit off. > > > > > > > > > > > > Hubble gives only two concievable explanations: > > > > > > > > > > > > > [a] Everything is flying away from us, placing us in the center of a > > > > > > > > > > > > bunch of stuff which is moving outwards, or > > > > > > > > > > > > [b] Space is expanding and is centerless. > > > > > > > > > > > > > I think that his options were incomplete. I think that either: > > > > > > > > > > > > > [a] Space is expanding and is centerless. > > > > > > > > > > > > [b] We are contracting away from space and it is centerless. > > > > > > > > > > > > > I think that both of these are valid possibilities, and that they > > > > > > > > > > > > should be equivalent under Equivalence Principle. > > > > > > > > > > > > Please. Stop with the gobbledygook. > > > > > > > > > > > The Principle of Relativity does NOT mean "everything is relative". > > > > > > > > > > > The Principle of Equivalence does NOT mean "opposite things are > > > > > > > > > > > equivalent." > > > > > > > > > > > > You can babble if you want. I just don't recommend that you attach > > > > > > > > > > > buzz phrases from pulp physics to the babbling. It will only put folks > > > > > > > > > > > off.- Hide quoted text - > > > > > > > > > > > So, the only time we can apply the Equivalence Principle is when we > > > > > > > > > > are looking at rectilinear motion. Cant apply it to anything else > > > > > > > > > > except trains and rockets. > > > > > > > > > > Nor did I say that. > > > > > > > > > You, the fuzzy logic champion, seem to veer quite dramatically from > > > > > > > > > Black to White. > > > > > > > > > "Well, if it means more than trains and rockets, then I can say it > > > > > > > > > means whatever I want, can't I?" > > > > > > > > > > > Ahem - > > > > > > > > > > > Space is a "physical thing". And whenever two physical things are in > > > > > > > > > > motion with respect to each other, relativity must apply. > > > > > > > > > > No, sir. This again is gobbledygook. > > > > > > > > > > > If one > > > > > > > > > > region of space (which is a thing) appears to be in motion relative to > > > > > > > > > > another, then I see no reason why these principles wouldnt apply.- Hide quoted text - > > > > > > > > > > - Show quoted text -- Hide quoted text - > > > > > > > > > > - Show quoted text - > > > > > > > > > Surely you would concede that expansion of space qualifies as "motion" > > > > > > > > of something. Something must be in motion, otherwise the concept of > > > > > > > > expansion is just vacuous. > > > > > > > > > If the universe were 1-dimensional, then it might be easier to see > > > > > > > > that something must be in motion. > > > > > > > > > Are we now arguing that something such as space can expand and that > > > > > > > > there was no motion involved in this process ? Doesn't that seem a bit > > > > > > > > contradictory ? > > > > > > > > First of all, the principle of relativity does not apply to any old > > > > > > > kind of motion. Nor does the principle of equivalence. > > > > > > > Secondly, there IS a difference between something moving from one > > > > > > > coordinate in space to another coordinate in space, and the metric of > > > > > > > space itself changing. > > > > > > > > Rather than muddling through with loose interpretations of terms that > > > > > > > are in fact carefully defined and delineated, don't you think it would > > > > > > > be beneficial if you actually learned some of the careful delineations > > > > > > > and definitions? > > > > > > > > Or is it more fun for you to just babble in free-association style, > > > > > > > hoping that you can defend some loose connection between your thinking > > > > > > > and what physics means by these things? > > > > > > > > PD- Hide quoted text - > > > > > > > > - Show quoted text - > > > > > > > There's more than one way to skin the cat, and as some of those ways > > > > > > are equivalent. Has to be. > > > > > > > All Im suggesting is that there is a maximal segment of time allowable > > > > > > by physics, and suggesting a way to estimate what it is. Age of > > > > > > universe based on big bang, added to time we've got left until the big > > > > > > crunch. > > > > > > What's the rationale that there is even going to be a big crunch? > > > > > Is your rationale the fact that you heard it on TV some time ago? > > > > > > > That would yield a cosmic counterpart to Planck Time, the > > > > > > maximal segment of time possible given contemporary physics.' > > > > > > It's only a counterpart in the sense that you would arbitrarily pair a > > > > > minimum with a maximum. > > > > > But this is like pairing a virus with a blue whale and implying that > > > > > they must be related. > > > > > > > I would actually calculate the time left until the big crunch based on > > > > > > a contracting spacetime, which I consider equivalent to an expanding > > > > > > one. > > > > > > > I dont really know where I might have muddled any definitions in that, > > > > > > but your perfectly welcome to criticize anyhting I say because frankly > > > > > > I have a certain amount of confidence that it's a worthwhile idea. > > > > > > Whether correct or not I do not know, but then again Im not the one > > > > > > funding things such as SETI am I. > > > > > > That's true, and so now I understand your gambit. > > > > > You perceive a lot of the research that is being done (like SETI) to > > > > > be pointless diddling exercises without real rationale or clear > > > > > thought. If they had a rationale or clear thought behind them, you > > > > > tell yourself, then you would understand and endorse the projects.. But > > > > > since you don't, then they must not have a well-considered > > > > > justification. That being said, you figure that you are just as > > > > > entitled to engage in a similar, pointless, diddling exercise without > > > > > much in the way of a well-considered justification or clear rationale. > > > > > And so you toss in your barely baked ideas, imagining that they must > > > > > be at least as baked as some of the other things you've seen in the > > > > > news. Perhaps you can get your slice of notoriety by tossing your > > > > > barely baked contribution into the ring. > > > > > > > Raises one eyebrow. > > > > > > > ?.- Hide quoted text - > > > > > > - Show quoted text -- Hide quoted text - > > > > > > - Show quoted text - > > > > > I was only joking about SETI. Personally I tend to believe that indeed > > > > we are not the only living things in this universe. It's not very > > > > reasonable to think that we are alone. > > > > > But the justification for a big crunch would be the idea that we are > > > > contracting away form space, causing redshift. Certainly we can only > > > > contract just so far until we are no more. > > > > Sorry, but that has nothing to do with the big crunch. In the big > > > crunch, objects in the universe are *approaching* each other, and > > > their radiation is blue-shifted. > > > > As I mentioned earlier, it helps to know what terms used in physics > > > actually mean, rather than just trying to "intuit" what they mean and > > > following implications of what you THINK they mean. But to do that > > > requires a little reading, which is apparently more effort than you > > > are willing to put out. > > > OK - so the term "Big Crunch" has already been coined many years ago > > to describe the death of the universe based on bgi bang cosmology, yes > > yes I concede, I stole a name that some else had already reserved for > > this other well known process which was described decades ago. > > > For that you have my apology. > > > However, the concept of a crunch of some kind is appropriate and so > > maybe I should distinguish my big crunch from pre-existing big > > crunches. So - the process I described, lets call it the "Big Smoosh". > > > Would that appease the powers that be ? > > I'll point out here that there is serious speculation that the > anisotropies seen in the CMBR can be attributed to anisotropic > expansion in different parts of the Universe (at different times as > well), and that some parts may even be contracting. > > http://www.google.com/search?q="anisotropic+expansion"+universe > > I can buy the anisotropic expansion part because AFAIK there's no > obvious mechanism to tie together the rates of expansion of two widely > separated parts of the Universe. > > As for the contraction part, not so much to my taste. One patch may > be expanding slower than the patch next to it and might *seem* to be > contracting by comparison, but that's about as far as I'm willing to > go. Locally, space would still appear to be expanding. > > It Seems To Me, anyway. I could be wrong. > > Mark L. Fergerson- Hide quoted text - > > - Show quoted text - It's easier to consider the 1-dimensional case. Consider that the universe is just 1-dimensional, and the universe in it's entirety is some finite segment of length. Somewhere along the line you have observer and light source, and the observer is seeing redshifted light. Assuming that observer and light source are not in motion with respect to each other, there are really only two possibilities; [1] Space is expanding in a neighborhood around the light source, or [2] Space is contracting locally in a neighborhood about the observer It's very unusual to think about things like this because you shouldnt be able to just create or destroy space by waving a magic wand. But, I think that it is possible to use conservation in such a way that the whole thing does make sense. And that neither [1] or [2] is absolutely correct, but that they are equivalent. I spent weeks talking about the equivalence of multiplication and addition in the trivial case where we are composing the existent with the nonexistent. It's pretty hard to argue against that.
From: Tim BandTech.com on 6 Aug 2010 09:26 On Aug 5, 6:37 pm, Huang <huangxienc...(a)yahoo.com> wrote: > On Aug 5, 3:33 am, "n...(a)bid.nes" <alien8...(a)gmail.com> wrote: > > >http://www.google.com/search?q="anisotropic+expansion"+universe > > > I can buy the anisotropic expansion part because AFAIK there's no > > obvious mechanism to tie together the rates of expansion of two widely > > separated parts of the Universe. > > > As for the contraction part, not so much to my taste. One patch may > > be expanding slower than the patch next to it and might *seem* to be > > contracting by comparison, but that's about as far as I'm willing to > > go. Locally, space would still appear to be expanding. > > > It Seems To Me, anyway. I could be wrong. > > > Mark L. Fergerson- Hide quoted text - > > > - Show quoted text - > > It's easier to consider the 1-dimensional case. Consider that the > universe is just 1-dimensional, and the universe in it's entirety is > some finite segment of length. > > Somewhere along the line you have observer and light source, and the > observer is seeing redshifted light. Assuming that observer and light > source are not in motion with respect to each other, there are really > only two possibilities; > > [1] Space is expanding in a neighborhood around the light source, or > [2] Space is contracting locally in a neighborhood about the observer > > It's very unusual to think about things like this because you shouldnt > be able to just create or destroy space by waving a magic wand. But, I > think that it is possible to use conservation in such a way that the > whole thing does make sense. And that neither [1] or [2] is absolutely > correct, but that they are equivalent. > > I spent weeks talking about the equivalence of multiplication and > addition in the trivial case where we are composing the existent with > the nonexistent. It's pretty hard to argue against that. Nice approach Huang. The question of what is fundamental has to be addressed so simply and carefully. Still, there is this nagging feeling I get when considering flexible space for now we must admit that we are discussing that flexibility from a flat context. This is the nature of the existing mathematics. Every one of us that makes an attempt using real numbers in the basis of such a theory will be admitting such, and if not consciously, then so be it. As soon as we ask for a quantification of the spatial expansion in a given region of space then we have crossed this line, for we have inherently expressed that a flat space could exist. At such times it is time to question the very language that we use. Such vacuous problems await a creative mind, for the only way through is by synthetis, and even our modern understanding that 'synthetic' means fake could be such a trite conflict as to steer us away. No, I think it is time to take back this word synthetic and give it more respect and meaning. Let's not forget how the Rove's of the world use language, and let's attempt to turn that invisible layer into a good force, rather than a bad farce. Transparency has two ways, or even more. The filtration of information nearly guarantees that we will not find the truth, except through some strange new route that can only be appreciated in hindsight. I find it especially interesting that you do consider a sum and product relationship, and that you attempt to create a new form of number. I do believe that you are on a good track. Coulomb's law and the Newtonian law of gravitation still hold up quite well, especially for static problems. These take the symmetrical form x1 x2 -------- r r and explode at distance zero, where these r's are real valued, though there is additionally some vector geometry in these expressions and here we've just got the magnitudinal portion. Wouldn't it be pretty if something were overlooked down here in the old guts? Then we could entertain a semiclassical theory, and I find this option very attractive, given the quantity of nonsense in the mainstream theories of our day. When did quantum theory recover the old charge force equation? Never to my knowledge, and so this can be a foundational attack on that quantum theory, for it derides the classical theory. By reconsidering the real number some options do open up, though I have to admit I am not fully happy with them. The most intriguing of these is the option of reconsidering the origin to be unity rather than zero. Next we can treat infinity as zero, and this means that distance takes on a much more accurate emperical meaning, for the things that are far away from us are less meaningful to our existence, whereas the things which are local to us are hardly zero. They are instead very much finite and substantial. It happens that when we perform this transformation on the classical form of interaction that we eliminate the mathematical conflicts, and arrive at a need for a unity type of distance. The transform of distance in magnitude (unsigned) form is Y = 1 / ( 1 + X ) where X is the usual distance that we are taught in grade school, and Y is this new transformed way of thinking. We can see that when X = 0, Y = 1 and when X = inf, Y = 0 and so the transform that I describe now has an origin which we can mark as unity, and places which we ordinarily call distant on the graph will be zero. This alleviates as well the human conception of infinity, which may actually be quite flawed, if this analysis is correct, in terms of continuum behaviors. This theory of this new number expresses that the continuum exists from unity to zero. Strangest of all, an existing tape measure will work with this new seemingly drastically altered statewith just two minor modifications. There is a crux here, though. A new critical measure that was unity in the old measurement system is now X = 1, Y = 1/2 but then, this is just how the new tape measure will read X = 2, Y = 1/3 and so forth; just as if you cut off the first inch of your existing tape and draw in a "1/" in front of every number. This is still the inch system if you had an inch tape measure to begin with. Why should this appear so challenging to absorb for the human? Well, it does run quite a modification on all of that programming that we've received since grade school days. The beauty of this transform is that the new semiclassical equations now read y1 y2 where their distance is all that exists, and their quantum values are inherent. At least, this is the level of thinking that I would like to get to. The standard classical equations exist as if we can take a large quantity of charge at one location, but we know that this only implies more integration at that region, until we get to a solitary charge, whose proper form can then take this simple product relationship. Is Plancks constant lurking here in a new form? Is there a proper 1/2 value in the new domain? Well, if you work in this paradimg a little bit longer you will start to see some issues, and some of them are precisely to do with the product and the sum type of algebra that we are accustomed to. This new metric that I describe is hardly flat, and if anything our own attachment to flat earth still exists. We are merely products of accumulation and having scraped near the bottom too happily move along into more accumulation. To ponder the fundamental is to declare all problems open, and they will stay that way, even if a better new answer is found. - Tim
From: nuny on 6 Aug 2010 10:25 On Aug 5, 3:37 pm, Huang <huangxienc...(a)yahoo.com> wrote: (brevity snip: re universal "Crunch" vs. local Smoosh") > > I'll point out here that there is serious speculation that the > > anisotropies seen in the CMBR can be attributed to anisotropic > > expansion in different parts of the Universe (at different times as > > well), and that some parts may even be contracting. > > >http://www.google.com/search?q="anisotropic+expansion"+universe > > > I can buy the anisotropic expansion part because AFAIK there's no > > obvious mechanism to tie together the rates of expansion of two widely > > separated parts of the Universe. > > > As for the contraction part, not so much to my taste. One patch may > > be expanding slower than the patch next to it and might *seem* to be > > contracting by comparison, but that's about as far as I'm willing to > > go. Locally, space would still appear to be expanding. > > > It Seems To Me, anyway. I could be wrong. > > It's easier to consider the 1-dimensional case. Consider that the > universe is just 1-dimensional, and the universe in it's entirety is > some finite segment of length. Unphysical according to GR, but irrelevant. > Somewhere along the line you have observer and light source, and the > observer is seeing redshifted light. Assuming that observer and light > source are not in motion with respect to each other, there are really > only two possibilities; > > [1] Space is expanding in a neighborhood around the light source, or > [2] Space is contracting locally in a neighborhood about the observer or [3] The light is climbing a gravity gradient toward the observer. Note this does *not* explicitly require a second dimension through which to bend 1D space. > It's very unusual to think about things like this because you shouldnt > be able to just create or destroy space by waving a magic wand. But, I > think that it is possible to use conservation in such a way that the > whole thing does make sense. And that neither [1] or [2] is absolutely > correct, but that they are equivalent. I mentioned anisotropic expansion because some of its supporters claim evidence in the CMBR suggesting we're in a locally "contracting" bubble a few dozen million ly across. The boundary (since we're talking about very-long-wavelength ripples spreading from the Big Bang, it's basically a gravitational gradient) is allegedly the source of the CMBR giving a false appearance to the rest of the Universe (implying other distant places may have a different, or even absent, CMBR), thus false age estimates for it. Whether there's anything to it remains to be seen. Mark L. Fergerson
From: Jacko on 6 Aug 2010 15:03
The centre of the universe. =================== The centroid of all the black holes weighted by mass in the local universe, with all their light cone of influence taken into account for bringing the 'final' mass to the centre. It is likely to be somewhere. Any two such accumulators not in each others light cone are seperate and may be different universes from this prospective. Centreless is a concept introduced by lazy estimators. ;-) Expansion by dark energy =================== Space warps atract mass. if not enough mass exists to go round some spacewarp will be left over having an apparent light bending mass, while not having enough gravity to stop the expansion effect. Why does light bend twice? The expansion of space by energy ========================= Does space expand on the inside to fill the external swartzchild radius? How slow can light get due to gravity? They may evolve faster on the outside, but I doubt they'd come close to the edge of our universe without joining our slow rate of light. Does the centre black hole universe model imply some oscillation of the size of space? Singularity contains an infinity with a singularity which contains an infinity ad infinitum? Endamology ========= What size does a black hole have to be before the sheer stress fracture effect is out weighed by the time dilation effect? Cheers Jacko http://community.city.ac.uk/netcommunity/jackokring |