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Thread: Big Bang Blown?

  1. #1

    Big Bang Blown?

    Well, I normally don't like to get into too much Big Bang bashing or anything, but I may have come up some important derivations. But first, please read through this thread and run through the calculations. I know I need to give everyone in that discussion time to look through them on that thread as well, but I'll go ahead and start this going in the meantime.

    Now, the time for light to travel to us while space is expanding is t=(e(Hd/c)-1), where H is the current value for the Hubble constant and d is the current distance to a galaxy from Earth (Hr and df). For a constant rate of expansion, Tuniverse=1/H, so let's find the furthest distance a galaxy can be where a pulse of light would just now be reaching us since the time of the Big Bang. That would be for t=T, so

    t=T=1/H=(e(Hd/c)-1)/H [EDIT-This should be /He. This thread is incorrect. Sorry. -grav]
    1=e(Hd/c)-1
    2=e(Hd/c)
    Hd/c=ein2
    d=(c/H)ein2

    That gives us d=1.03972*10^26 meters for c=3*10^8 m/sec and H=2*10^-18 sec-1. This value for d is the final distance travelled over that time, df, so let's find the original distance, do.

    do=df/[e(H*df/c)] and e(H*df/c)=2, so
    do=df/2=5.1986*10^26 meters

    The question is, then, if all galaxies once existed at a singularity (or close to it), then how can galaxies at the furthest distances have started out at only half that distance, far from a singularity? Also, how can we observe galaxies much further than this if the light would have taken more time to reach us than the age of the universe? The only answer I can think of is that the expansion model is either incorrect or in need of some tremendous alterations. Is the Big Bang model blown?
    Last edited by grav; 2006-Dec-07 at 04:12 AM.

  2. #2
    The way I understood it, the physics as we know them and as you applied, were not valid in the first time after the big bang. Only when things settled (for very small values of settling), physics became the way we know them. I'm no expert though.

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    Quote Originally Posted by grav View Post
    The only answer I can think of is that the expansion model is either incorrect or in need of some tremendous alterations.
    No other possible answers cross your mind?
    Everyone is entitled to his own opinion, but not his own facts.

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    The current expansion model assumes space itself is expanding - the space between the galaxies, not the distance traveled in fixed space. This means the total distance can be much greater than the light-time limited velocity. Yes, this not logical to many of us, and it does violate conservation of energy, and it does require an inflationary episode that is not understood by anyone, and is now sprinkled with equally mysterious dark matter and dark energy, so we have one universe and three mysteries. But we are absolutely certain about how it all started...and it is turtles all the way down.

  5. #5
    Quote Originally Posted by Nicolas View Post
    The way I understood it, the physics as we know them and as you applied, were not valid in the first time after the big bang. Only when things settled (for very small values of settling), physics became the way we know them. I'm no expert though.
    I am finding it for the maximum distance that can be derived during the entire time for expansion, using the model for constant expansion as it now stands. To say that physics changes somewhere along the way would require another cosmological model altogether, dramatically different than the one I am using, that explains how this comes about.

  6. #6
    Quote Originally Posted by Cougar View Post
    No other possible answers cross your mind?
    Well, the gravity of a limited mass in a limited space would help matters some, but still shouldn't change things all that much. Besides, the expansion is actually supposed to be accelerating, not decreasing, and there is only one cosmological model I can think of to explain redshifts in that regard, but I won't go there. What do you have in mind?

  7. #7
    Quote Originally Posted by Jerry
    ...and it is turtles all the way down.
    Yes. That seems just as likely.

  8. #8
    Quote Originally Posted by grav View Post
    Well, the gravity of a limited mass in a limited space would help matters some, but still shouldn't change things all that much. Besides, the expansion is actually supposed to be accelerating, not decreasing, and there is only one cosmological model I can think of to explain redshifts in that regard, but I won't go there. What do you have in mind?
    Actually, scratch that. I just realized even gravity would have no affect on the universe as a whole. If the universe has no definable boundaries, then it has no definable center, which I think we can all agree, so each galaxy has no definable direction in which to "fall". I know people like to think outside the box with this, but for galaxies that exist within it, there is no outside, and there is no center, and so they will only be pulled in every direction at once, or not at all, which amounts to equilibrium for gravity either way.

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    Is redshift due to recession or optics? Whether or not we understand the properties completely, the optical solution would provide a far, far less complicated model.

    Big Bang adherents like to point out what it explains, but Inflation and dark energy are both very significant patches designed to cover divergences between theory and observation.

    I would still like to see an explanation for why C doesn't increase proportionally to the expansion of space and why this wouldn't imply a pre-existing dimension of space, which would contradict BBT.

  10. #10
    Quote Originally Posted by Nicolas View Post
    The way I understood it, the physics as we know them and as you applied, were not valid in the first time after the big bang. Only when things settled (for very small values of settling), physics became the way we know them. I'm no expert though.
    Can anyone who has read up on BBT give info on this?

  11. #11
    I just realized something. df/do=e(Hd/c) is the same as that for tired light theory, as in my own cosmological model, since the wavelengths of light will also expand in proportion to space while in transit, so wo/we=df/do=e(Hd/c). So the two theories are now mathematically the same in that respect. Also, since the redshifts are in proportion to e(Hd/c)-1 instead of directly with Hd/c-1, so that it is not directly proportional to the distance after all, then this would account for an apparent acceleration of the expansion either way, when measured in respect to the ratio of redshift to distance. In addition to this, expansion theory works out for the observed redshift according to these calculations. z=1 means the wavelength has doubled, so the size of the universe should have doubled as well. In my first post in this thread, we found that light that has been travelling for the entire age of the universe would have come from when the universe was half as large and distances half as great, for a redshift of z=1. Since the current distance would then be (c/H)ein2 at the "edge" of the observable universe, where we would then observe a redshift of z=1, this agrees with expansion theory, but not with Big Bang theory, which says it originated at a singularity. There are still two big problems that I see with expansion theory, however. One, we should never see a redshift greater than z=1, except where peculiar radial velocities are concerned, since that would require a time of transit for light greater than the age of the universe. And two, if the light from a galaxy at (c/H)ein2, the edge of the observable universe, originated at half that distance, then the universe must have been half its size when it began to expand. But in twice the present age of the universe, the same galaxy will exist at that same edge, since it will have travelled with the expansion, but we would say then that the expansion started at half that distance as well, which would place it back at its present size before expansion took place to begin with, at T=0. So regardless of whether or not physics has changed somewhere along the line, with the present rate of expansion, and in twice the present age of the universe, we should be saying that the universe was the present size at T=0, which would obviously be incorrect.
    Last edited by grav; 2006-Dec-06 at 05:29 AM.

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    You've mostly answered your own question grav. Cosmological redshift stretches space, along with the wavelengths of light passing through that space. In that sense, light speeds up as space expands. We can detect CMB photons, which are older than any galaxy could be. The observational limit of our universe has always been the surface of last scattering, so far as photons are concerned. Neutrinos, however, are another story. In principle, we should be able to detect them back to the first second after the big bang.

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    Quote Originally Posted by Thanatos View Post
    You've mostly answered your own question grav. Cosmological redshift stretches space, along with the wavelengths of light passing through that space. In that sense, light speeds up as space expands. We can detect CMB photons, which are older than any galaxy could be. The observational limit of our universe has always been the surface of last scattering, so far as photons are concerned. Neutrinos, however, are another story. In principle, we should be able to detect them back to the first second after the big bang.
    If light is speeding up proportional to the expansion of the universe, does that mean that at the singularity, the speed of light was zero?

    If light is speeding up as space expands, why is it redshifted? It would seem that redshift is the tension between a constant speed of light crossing an increasing distance.

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    Excellent Observation

    Quote Originally Posted by brodix View Post
    ...

    If light is speeding up as space expands, why is it redshifted? It would seem that redshift is the tension between a constant speed of light crossing an increasing distance.
    That is the million dollar question!!! If the speed of light varies with the age of the universe then nothing would change due to the age/expansion state of the universe.

    The universe would actually appear to be growing smaller as we look deeper into the past because our meterstick grows proportionately with respect to the varying speed of light.

  15. #15
    Quote Originally Posted by Thanatos View Post
    You've mostly answered your own question grav. Cosmological redshift stretches space, along with the wavelengths of light passing through that space. In that sense, light speeds up as space expands. We can detect CMB photons, which are older than any galaxy could be. The observational limit of our universe has always been the surface of last scattering, so far as photons are concerned. Neutrinos, however, are another story. In principle, we should be able to detect them back to the first second after the big bang.
    Yeah, what Brodix said. Also, if light speeds up, starting off very slowly, then the observable universe should be even smaller than what we actually observe, since the light will not have reached us within a time of T=1/H. If it slows down, beginning with some very high value, then the current distance to galaxies would be even closer to their observed distance for when the light was emitted. And I am considering the effect as seen from the surface of last scattering. The fact that we believe we are receiving light from a time before the galaxies formed has nothing to do with the age of the universe itself, as measured by 1/H. The fact that we observe redshifts greater than z=1, however, should indicate a static universe, so that we could detect light as far back in time as our telescopes allow, since there would then be no expansion or T=0 to limit us.

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    Quote Originally Posted by Nicolas View Post
    Can anyone who has read up on BBT give info on this?
    The further back in time = the closer you get to t=0, the less precise the physics we know today, here on the Earth, is, in terms of describing the state of the universe at that (early) time.

    For example, the era of nucleosynthesis is pretty well constrained, because this density/energy regime is well understood in terms of nuclear physics (both theoretical and experimental). At the time when densities and energies were so high that the universe was a quark-gluon soup (a different kind of plasma), many details are vague (the nature of this kind of plasma is only now being explored in experiments). Beyond the energy of the CERN, Fermilab, etc accelerators, we have only the standard model (of particle physics) - a theory - to guide us, and that is already known to be incomplete.

    The limit is the Planck regime - where the mutual inconsistency of GR and quantum theory is overwhelming. In this regime, each of these highly successful theories, applied on its own, produces results that are nonsense in terms of the other. So unless and until there is a theory which replaces one or the other (or both), we can say nothing about physics in this regime (except, of course, to speculate - string theory for example).

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    Quote Originally Posted by brodix View Post
    If light is speeding up proportional to the expansion of the universe, does that mean that at the singularity, the speed of light was zero?

    If light is speeding up as space expands, why is it redshifted? It would seem that redshift is the tension between a constant speed of light crossing an increasing distance.
    All good questions.

    However, without a theory that is at least as good as GR (in terms of being validated, experimentally and observationally) there is no way to answer any of them.

    Do you have such a theory (in the scientific sense) that you would like to put on the table, for us to challenge?

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    Quote Originally Posted by Squashed View Post
    That is the million dollar question!!! If the speed of light varies with the age of the universe then nothing would change due to the age/expansion state of the universe.

    The universe would actually appear to be growing smaller as we look deeper into the past because our meterstick grows proportionately with respect to the varying speed of light.
    Nonsense.

    A varying speed of light (in the sense that you mean it here) is incompatible with GR, so the second paragraph is meaningless (all the terms in it have meaning only within a theory that contains the relevant components of relativity).

    If you zero-out one part of relativity, you cannot use the rest of it to ask meaningful questions (without at least stating very clearly just how internal consistency is attained ... and showing that consistency, quantitatively).

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    That's What I Thought

    Quote Originally Posted by Nereid View Post
    Nonsense.

    A varying speed of light (in the sense that you mean it here) is incompatible with GR, ...
    That's what I thought but then I read Bob Angstrom's post which seemed like it was accepted or at least not challenged so that is where the thoughts of my post originated.

  20. #20
    I think I might be able to come up with a way to compare the redshift for light travelling at a constant speed during expansion and that for the speed of light increasing in proportion to the size and age of the universe, both for a constant expansion rate. It may take may a while to do this, however, but we should then be able to see which one would give us redshifts that increase in direct proportion to expansion during the time of travel, which is the basis for the theory.

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    Quote Originally Posted by Nereid View Post
    A varying speed of light (in the sense that you mean it here) is incompatible with GR, so the second paragraph is meaningless (all the terms in it have meaning only within a theory that contains the relevant components of relativity).
    That's the meaning of my question as to why doesn't C increase as space expands. The fact that C remains constant means it is measuring a stable dimension of space, yet the assumption that space is expanding is based on the observation that the spectrum of light is redshifted. There are two large problems this raises for BBT. If this is an expansion in space, not of space, observations of consistant redshift in all directions would mean we are at the center of the observable universe. Also it would make Inflation unfeasible, because pre-existing space would be subject to quantum phenomena and the pressure wave would be overwhelming. This would make non-inflationary expansion more complicated as well.

    However, without a theory that is at least as good as GR (in terms of being validated, experimentally and observationally) there is no way to answer any of them.

    Do you have such a theory (in the scientific sense) that you would like to put on the table, for us to challenge?
    I did put it forward in the, Question: Why doesn't C increase thread, but I'll repeat the basic premise.
    The original impetus for this was in considering that Omega=1. It seemed that if observed expansion was evenly balanced by the effect of gravity on space, then it seemed likely these were opposite effects. While gravity causes our ability to measure space to contract, it does so against a stable abstract. We know it bends light because we compare it against this
    Euclian dimension. It is a lensing effect. So if expansion is the opposite, then it is an opposing lensing effect. Redshift, as it is observed, is clear evidence of this. Whatever direction we look, space is curved away from us, so that everything appears to be flying directly away from us and the further light travels, the more it is curved, so that the faster its source appears to be flying away from us.
    The question is what causes this opposing curvature. It seems the likely candidate is light itself. Gravity causes mass to collapse into its well and compresses it to the point it ignites and radiates back out. So mass goes the direction of gravity, but radiation goes the other direction. Every point in space is crossed by radiation from every direction. Could these intersecting waves cause interference patterns, like waves crossing on the water combine, creating larger waves, so that any one wave seems to be bent and crossing more space then it should?

  22. #22
    Quote Originally Posted by grav View Post
    I think I might be able to come up with a way to compare the redshift for light travelling at a constant speed during expansion and that for the speed of light increasing in proportion to the size and age of the universe, both for a constant expansion rate. It may take may a while to do this, however, but we should then be able to see which one would give us redshifts that increase in direct proportion to expansion during the time of travel, which is the basis for the theory.
    Sorry, guys. After I determine how the speed of light should vary during expansion according to the redshift, I'm scrapping this thread and starting completely over with a new one, 'Expansion and the speed of light', in which I will rewrite all calculations so far, by basically starting over from scratch. In the very first post of this thread, I wrote t=T=1/H=(e(Hd/c)-1)/H, but that should have been t=T=1/H=(e(Hd/c)-1)/He. So what I said about receiving light from a galaxy at the edge of the universe originating when it was half that distance is incorrect, along with the equation d=(c/H)ein2, then, which is unfortunately about half of everything I've had to say in this thread so far. Everything in the thread in Q&A still stands, though. I'm going to take Grey's advice, however, and from now on, in order to avoid confusion (including my own), I will only express the values for d, H, c, and T followed by e or r for the time of emission or when received, except when referring to the present values. That way, this hopefully will not happen again. I hope this doesn't cause anyone to lose any faith in me with this. To err is human, as they say.

    I guess the one most important thing to salvage in this thread, however, is that z+1 for redshift is e(Hd/c), and so is not directly proportional to distance, and should explain the apparent accelerated expansion of the universe. It is also the same for tired light theory, however, so the formula stands either way.
    Last edited by grav; 2006-Dec-09 at 01:12 AM.

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    Quote Originally Posted by Nereid View Post
    Nonsense.

    A varying speed of light (in the sense that you mean it here) is incompatible with GR, so the second paragraph is meaningless (all the terms in it have meaning only within a theory that contains the relevant components of relativity).

    If you zero-out one part of relativity, you cannot use the rest of it to ask meaningful questions (without at least stating very clearly just how internal consistency is attained ... and showing that consistency, quantitatively).
    Einstein’s GR only insists that the speed of light be the same in every inertial frame of reference but the universe is not a single inertial reference frame so this restriction of GR does not apply. If the speed of light could not vary, it would be impossible for a beam of light to curve in the vacuum of space and there would be no such thing as gravitational lensing. Or if the speed of light could not accelerate to keep pace with the expansion of space, then old light would appear to travel slower than new light. Light from the distant past gains energy as it accelerates while simultaneously losing energy by redshifting so the total energy is conserved.

    For the sake of simplicity, we can say that the rate of time (how fast the clock ticks) has remained the same throughout the ages while space expands. This is a common assumption when we say that space is expanding. If space is expanding and time is unchanging, then the speed of light must accelerate as space expands. We can designate either time or the speed of light as absolutes but the essential thing to remember is that they can not BOTH be constants within the same model.

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    Quote Originally Posted by Bob Angstrom View Post
    Einstein’s GR only insists that the speed of light be the same in every inertial frame of reference but the universe is not a single inertial reference frame so this restriction of GR does not apply. If the speed of light could not vary, it would be impossible for a beam of light to curve in the vacuum of space and there would be no such thing as gravitational lensing.
    Isn't the whole point of GR that it is the reference frame, ie. space, that is curved? The speed of light can vary, but C is the speed of light in a vacuum.

    Or if the speed of light could not accelerate to keep pace with the expansion of space, then old light would appear to travel slower than new light.
    If the speed of light remained the same, then it would appear much faster in the past, because the distance it was crossing would be smaller. That's why it would need to accelerate.

    Light from the distant past gains energy as it accelerates while simultaneously losing energy by redshifting so the total energy is conserved.
    If it is accelerating, why would it be redshifted? If the speed of light is accelerating at the same rate the inertial frame of space is expanding, then the source of that light would not appear to be receding, because the most fundamental ruler we have, C, is stretching. If the speed of light is constant to the distance, frequency would be the same. It's amplitude that would lose energy.

    The light from a source that is being radiated in all directions should be losing energy anyway, because the further it travels, the greater the volume of space it must fill, since the speed remains at C, presumably frequency remains the same, so it is amplitude that is lost.


    For the sake of simplicity, we can say that the rate of time (how fast the clock ticks) has remained the same throughout the ages while space expands. This is a common assumption when we say that space is expanding. If space is expanding and time is unchanging, then the speed of light must accelerate as space expands. We can designate either time or the speed of light as absolutes but the essential thing to remember is that they can not BOTH be constants within the same model.
    To the photon, there is no time and the closer you get to C, the slower time goes, because combined motion and internal atomic motion cannot exceed C. So if you are going to say that C increases, then you are saying time speeds up as well.

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    Quote Originally Posted by grav View Post
    ...After I determine how the speed of light should vary during expansion...
    I don't know about all your calculations, but it seems you are leaving out an important consideration, and that is, WHO are you considering to be measuring the speed of light? Einstein simply said that WHOEVER measures light's speed, wherever they are and in whatever state of motion, it will turn out to be the same.

    Aren't you forgetting the observer in all this? Are you taking a "god's-eye view" of the situation? I could be wrong, but I believe this will often lead to incorrect conclusions.
    Everyone is entitled to his own opinion, but not his own facts.

  26. #26
    Quote Originally Posted by Cougar View Post
    I don't know about all your calculations, but it seems you are leaving out an important consideration, and that is, WHO are you considering to be measuring the speed of light? Einstein simply said that WHOEVER measures light's speed, wherever they are and in whatever state of motion, it will turn out to be the same.

    Aren't you forgetting the observer in all this? Are you taking a "god's-eye view" of the situation? I could be wrong, but I believe this will often lead to incorrect conclusions.
    Speed is relative, so I am only calculating the speed of light as observed by the emitting galaxy at the time of emission and by the receiving galaxy upon reception. The two galaxies are considered to be stationary to each other, but the distance between them is expanding with time. In other words, a pulse of light is travelling between two stationary galaxies at a constant rate of speed, but the distance scales are increasing in the meantime, and the apparent speed of light, then, is the constant 'c' only in local frames.

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    Quote Originally Posted by brodix View Post
    Isn't the whole point of GR that it is the reference frame, ie. space, that is curved? The speed of light can vary, but C is the speed of light in a vacuum.
    Yes, GR gives us a workable and convenient reference frame but it is important to remember that c can only be an absolute if both space and time vary in such a way that the speed of light remains the same for all observers.
    Quote Originally Posted by brodix View Post
    If the speed of light remained the same, then it would appear much faster in the past, because the distance it was crossing would be smaller. That's why it would need to accelerate.
    If we could go back in time and observe light when distances were shorter it would appear no different from modern light because time would also be slower. The ‘acceleration’ of light is strictly theoretical, as is the expansion of space, and not something that can be directly observed. The observed speed of light is constant while expansion requires that it be accelerating.
    Quote Originally Posted by brodix View Post
    If it is accelerating, why would it be redshifted? If the speed of light is accelerating at the same rate the inertial frame of space is expanding, then the source of that light would not appear to be receding, because the most fundamental ruler we have, C, is stretching. If the speed of light is constant to the distance, frequency would be the same. It's amplitude that would lose energy.

    The light from a source that is being radiated in all directions should be losing energy anyway, because the further it travels, the greater the volume of space it must fill, since the speed remains at C, presumably frequency remains the same, so it is amplitude that is lost.
    The expansion of space also expands the length of a light wave making it appear longer and of a lower frequency, in other words, redshifted. Time is also accelerating as space expands making frequencies of ancient light appear longer. Time is the other half of the effect that needs to be considered.
    Quote Originally Posted by brodix View Post
    To the photon, there is no time and the closer you get to C, the slower time goes, because combined motion and internal atomic motion cannot exceed C. So if you are going to say that C increases, then you are saying time speeds up as well.
    Expansion accelerates c but the speeding of time makes c appear slower. The two effects cancel and the observed c remains unchanged.

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    Quote Originally Posted by Bob Angstrom View Post
    Yes, GR gives us a workable and convenient reference frame but it is important to remember that c can only be an absolute if both space and time vary in such a way that the speed of light remains the same for all observers.

    If we could go back in time and observe light when distances were shorter it would appear no different from modern light because time would also be slower. The ‘acceleration’ of light is strictly theoretical, as is the expansion of space, and not something that can be directly observed. The observed speed of light is constant while expansion requires that it be accelerating.
    Presumably the "expansion" of space is not theoretical. That's why there is redshift.

    The expansion of space also expands the length of a light wave making it appear longer and of a lower frequency, in other words, redshifted.
    Increasing distance between source and observer would redshift the light.

    The reason tired light theory does not work is because frequency is dependant on the speed of light and C doesn't change if there is no medium in the vacuum to slow it, so if C were to accelerate as space presumably expanded, it would cancel any redshift.

    Time is also accelerating as space expands making frequencies of ancient light appear longer. Time is the other half of the effect that needs to be considered.
    Expansion accelerates c but the speeding of time makes c appear slower. The two effects cancel and the observed c remains unchanged.
    You just said in your previous post that time was unchanging? As I pointed out, accelerating C would speed time, but this effect, with expanding space, would cancel redshift.

    Redshift is caused by increasing distance in stable space and C determines the stable space. So the problem is that we have increasing distance, due to expanding frequency and stable space due to C. Big Bang theory is so strong because of this connection between frequency and C. It is the original assumption that these galaxies must be moving away from us, due to their expanded frequency. Now we cannot measure the speed of light as it is going from distant galaxies to us. We can only measure the frequency. That tells us the distance must be expanding. The mistake was trying to say that space itself was expanding, since observations would otherwise put us at the center of the universe. But since our fundamental measure of space is C, it contradicts the original premise, because increasing C would cancel the redshift.

    We describe the effect of gravity on space as curving it, because that is what the path of something moving through it does, but a more accurate description might be that this space is compressed, so that an object moving into a gravitational field will naturally be pulled toward the source of the gravity. Now if radiation has the opposite effect, then it expands space, but there is no object it would be pulled toward, or pushed away from, so its path wouldn't necessarily be curved, but it would be constantly stretching. The reason this doesn't mean the entire universe is expanding is that this stretching is flowing into gravity wells, ie. Omega=1. Sort of like ocean floors are expanding, but the earth is not expanding because this additional area gets pushed under continents.

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    Quote Originally Posted by grav View Post
    Speed is relative....
    Except for the speed of light.
    Quote Originally Posted by grav View Post
    The two galaxies are considered to be stationary to each other, but the distance between them is expanding with time.
    Well, then they're not "stationary" relative to each other.

    Quote Originally Posted by grav View Post
    In other words, a pulse of light is travelling between two stationary galaxies at a constant rate of speed, but the distance scales are increasing in the meantime...
    Why put yourself through this?
    Everyone is entitled to his own opinion, but not his own facts.

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    Quote Originally Posted by grav
    The question is, then, if all galaxies once existed at a singularity (or close to it), then how can galaxies at the furthest distances have started out at only half that distance, far from a singularity? Also, how can we observe galaxies much further than this if the light would have taken more time to reach us than the age of the universe? The only answer I can think of is that the expansion model is either incorrect or in need of some tremendous alterations. Is the Big Bang model blown?
    Well, I still expect that the answer is c: there's a problem with your math. But regardless of the math, this statement is inaccurate. The farthest back that we can currently detect is the CMB, which is still 300,000 years after the big bang. Any galaxies that we can see formed somewhat after that. So there's no expectation at all that any galaxies that we can see now should have had a remarkably small initial distance.
    Conserve energy. Commute with the Hamiltonian.

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