Observational evidence against expanding universe in MNRAS

[Dale]

Why don't we limit it to the question of whether the data sets used in my paper do in fact contradict the predictions of the expanding universe hypothesis?

They do not appear to do so to me. In fact they seem to show good agreement at large distances, as expected, and to deviate at smaller distances, also as expected. The deviation even seems to occur on the order of the scale expected from other sources.

I am not saying that the paper is not worth publishing, but it is also not a death knell for standard cosmology as you seem to wish. I think you need to put your work in perspective.

 

[rootone]

would advocate that such topics be discussed in a different thread just to keep things orderly.

Some interesting conversation happens in the PF lounge,https://www.physicsforums.com/forums/general-discussion.14/

Eeek what is my phone doing:
I said 'interesting', not intermarriage whatever that is,

 

[PeterDonis]

try this

I'll take a look, but this is a 95 page paper. Is there a particular part of it that you think addresses the objection I raised?

 

[elerner]

Peter, it shows that observationally that the number of galaxies in a volume increases as the square the radius, not the cube. I gather you did not look up "fractals" on the web, so I will describe one. Imagine a checkerboard of 4 squares with the upper right and lower left one black. Now put two identical such patterns in a twice as large square so that they occupy the upper left and lower right corners. Then put that twice as large pattern in a twice as large pattern in the same way--and so on indefinitely. You can see that in this two-dimensional space the area that is black will increase linearly with radius, not as the square of the radius. It is a fractal of dimension 1. By analogy a similarly nested set of structures can--and does--form a 2D fractal in a 3D space. You can go out from any point and still get a mass that increases as the square, not the cube, of the radius. There is a vast literature on fractals, but I am sure you can find some brief descriptions on websites.

 

[elerner]

They do not appear to do so to me. In fact they seem to show good agreement at large distances, as expected, and to deviate at smaller distances, also as expected. The deviation even seems to occur on the order of the scale expected from other sources.

As expected by who, Dale? You? Find for me any published paper that "predicted" that galaxies near to us are two or three times bigger than the average in the present-day universe. You can't . No one has written this. This is purely your speculation, no citation, which I gather you get to write on this forum because you are a moderator.

As I posted earlier, if you want to test your hypothesis that there is a 2-3 fold variation in mean galaxy size over volumes of 200-800 Mpc, we can do that by looking at different parts of the sky. You want to bet that we will find a 2-3 fold variation? Will you accept this as a a test of your personal hypothesis? Because if you accept this, I can do the comparison very quickly as I have the data needed already from GALEX.

 

[PeterDonis]

it shows that observationally that the number of galaxies in a volume increases as the square the radius, not the cube

I understand that that is what the paper claims to show, yes. I have not read it through or tried to work through how it actually derives this conclusion, which does not appear to be generally accepted by cosmologists, from the data.

I gather you did not look up "fractals" on the web

I didn't have to. I already know what fractals are. The questions I am asking about your description of the model in question are not because I need to have the concept of fractals explained to me. They are because the claims you were making, in the specific form you were making them, appear to me to be self-contradictory. Throwing around the word "fractal" does not address that kind of question.

From what I have read so far in the paper you linked to, it does not seem that your claim that every point in a fractal matter distribution is the same as every other point is correct. The paper clearly distinguishes between fractal and homogeneous distributions; the statement that every point is the same as every other point only applies to homogeneous distributions. The paper also clearly describes why fractal distributions are not homogeneous: because in fractal distributions, the points where the actual matter exists (the paper calls them "structure points") are different from points that lie in the voids between the matter. The claims about how much matter exists in a sphere of radius $D$ about a given point, and how that quantity varies with $D$, only apply if the point in question is a structure point; they do not apply if the point in question lies in one of the voids. From the paper's description, all of the structure points within a fractal distribution appear to be identical, yes; but not all points are structure points.

Btw, the paper also says that the model it is describing is not fractal out to arbitrary distances from a given point; there is a distance scale $R_{\text{hom}}$ above which the distribution becomes homogeneous. The key question from the paper's point of view appears to be what the correct value of $R_{\text{hom}}$ should be; it says that it was assumed at first to be around 10 Mpc, but now a value of at least 100 Mpc seems to be the best fit to the data. That distance still corresponds to a fairly small redshift (about z = 0.013, based on the numbers you give in an earlier post), so the model the paper appears to be favoring would not be expected to have a fractal distribution at most redshifts (since IIRC we can see quasars out to about z = 6).

 

[Dale]

As expected by who, Dale? You? Find for me any published paper that "predicted" that galaxies near to us are two or three times bigger

You are still missing the point. The model does not make any predictions for small scales. It is expected to fail at small scales. The model deliberately, specifically, and explicitly limits its predictions only to very large scales. It doesn’t matter how much or in which direction it fails locally. You cannot falsify a model which only makes predictions for large scales by showing that it fails only for small scale data.

See http://arxiv.org/abs/0808.0012 chapter 6 for a good discussion of how this works

As I posted earlier, if you want to test your hypothesis that there is a 2-3 fold variation in mean galaxy size

That is not my hypothesis, I am not making any hypothesis. I am merely pointing out your fallacy of trying to use small scale data to falsify a model that explicitly makes predictions only at large scales.

 

[elerner]

Dale, the Tolman test has no limits on its applicability. Again, you are inventing some model out of thin air that is nowhere in the literature. Find me any paper that says there are limits on the applicability of the expanding universe formula of surface brightness. It applies anywhere the Hubble relation applies. You want to find papers that say there is no Hubble relation on scales of 200Mpc ( which are the scales in fact where it was first discovered)?

 

[Dale]

Dale, the Tolman test has no limits on its applicability.

The cosmological model does. Are you trying to falsify the cosmological model or the Tolman test?

https://en.m.wikipedia.org/wiki/Cosmological_principle
http://www.as.utexas.edu/astronomy/education/spring05/komatsu/lecture11.pdf
http://www.springer.com/cda/content/document/cda_downloaddocument/9783642540820-c2.pdf?SGWID=0-0-45-1481916-p176497146

 

[elerner]

Peter,
The reason I think you need to familiarize yourself a bit with the mathematics of fractals is that in an earlier post you were attempting to prove that fractals of dimension D=2 could not exist in a 3D space. So, I was trying to show you that indeed such a mathematical concept of fractals (which have dimensionality different than the space they are embeded in) is indeed well-developed and well-proven. I referenced that observational paper to show observational evidence that in the nearby universe, the distribution of mater is indeed a fractal of dimension D=2. I did not claim that it has been demonstrated that the distribution is fractal out as far as we can observe. But we do see larger and larger structures as far as we can observe, so the possibility is open that the fractal distribution extends very far out. If the density of matter gets low enough, GR becomes a negligible correction on scales of the observable universe.

 

[elerner]

Show me any reference that says the Tolman relation, based on the expansion of the universe, does not apply to all scales where the expansion of the universe applies. Are you saying there are published papers saying that expansion does not exist within 800 Mpc? The only small scales excluded by the expansion hypothesis are those that are gravitationally bound and therefore not assumed to be expanding. Again you are inventing out of thin air a restriction that in no way appear in the published literature. Show me one citation to support your speculation.

 

[Dale]

Show me any reference that says the Tolman relation, based on the expansion of the universe, does not apply to all scales where the expansion of the universe applies.

Why should I? I have shown references that support my actual point, not the straw man point you wish I were making.

Are you or are you not trying to show evidence against the standard LCDM cosmology? If you are, then your data do not provide that evidence, for the reasons I stated: The cosmological model only claims to work at large scales and your data shows that, according to the Tolman test, in fact it does work at large scales.

 

[elerner]

The cosmological model only claims to work at large scales .

Your personal cosmological model, I guess, but show me one citation that says the expansion hypothesis, which is what I am testing, does not apply on scales of 800 Mpc.

 

[Chronos]

Can you elaborate on the apparent suggestion that the surface brightness and angular diameter of galaxies is in conflict with special relativity and/or their inferred distances are in error.

 

[PeterDonis]

in an earlier post you were attempting to prove that fractals of dimension D=2 could not exist in a 3D space

No, I was showing that your particular claim about a so-called "fractal distribution" was self-contradictory. If you drop the (incorrect) claim that every point (instead of just every structure point) in a fractal distribution is identical, there is no problem having a fractal distribution of dimension D=2 in 3D space.

the possibility is open that the fractal distribution extends very far out

"Very far out" relative to the scales we can observe, yes. But that's still infinitesimal compared to the total spatial size of the universe, if the universe is spatially infinite.

If the density of matter gets low enough, GR becomes a negligible correction on scales of the observable universe.

Which just means the observable universe is spatially flat, to within our observational error--which the current mainstream cosmological model says it is anyway. But this does not entail that GR is a "negligible correction" on the scale of the entire universe. If the entire universe is spatially infinite, which the current mainstream cosmological says it is, then GR is not at all "negligible" on the scale of the entire universe.

 

[Dale]

Your personal cosmological model, I guess,

Nope, see the references I did post. All of them clearly state that the universe is only assumed to be homogenous and isotropic at large scales. Nothing personal about that. Perhaps you need to take an introductory cosmology course.

The “at large scales” assumption is ubiquitous. It is literally one of the foundational assumptions. At large scales -> homogenous and isotropic assumed to apply -> with GR gives FLRW -> with observations gives LCDM. Take away the initial assumption and the rest goes away too.

This is not my personal idea. This is just me pointing out the assumptions of the model, which you appear to be overlooking. You would rather attack a straw man LCDM that claims to work at all scales rather than the actual model, which clearly claims to work only at large enough scales.

show me one citation that says the expansion hypothesis, which is what I am testing, does not apply on scales of 800 Mpc.

It is getting a little tiresome asking me to post references for points that I am not making. Next time you ask me to provide a reference, please quote me exactly to indicate which of my actual comments you want a reference for.

 

[alantheastronomer]

elerner - The discrepancy you point to in the first figure of your press release can be resolved by modeling an accelerating universe, not a constantly expanding one. Apart from that, kimbyd is correct in pointing out that if there is an inconsistency between the properties of galaxies and the expansion of the universe, it is most likely that our knowledge about galaxies needs to be revised. If galaxies in the early universe, for example, didn't merge from smaller parts but were formed whole soon after recombination( which by way of the cosmic microwave background is more evidence(and more compelling) for an expanding universe) then that would eliminate your objections.

 

[elerner]

Dale,
I can make little arrow diagrams too.

Expanding universe hypothesis at all scales->Tolman's analysis at all scales->prediction of increasing apparent radius at distance beyond z=1.25 and specific quantitative relation of galaxy sizes at all z to size at z=0.

That last prediction is what is contradicted by observation. No matter what you assert, you can't find one published reference, and you have not cited one, that limits the predictions that my paper tested to any scale on which the Hubble relation operates. The Hubble relation has been observed down to scales of 10 Mpc, far below any scales measured in my paper. So your assertion that the expanding universe hypothesis only operates at large scales is without any support.

And, Alantheastronomer, you can read Tolman's orignal papers. The calculation applies to ALL expansion, irrespective of rate. The only assumption is that the Hubble relation is due entirely to expansion. For all such models, the surface brightness of identical objects decreases as exactly (1+z)^3.

It is true that to test this hypothesis, you have to assume a luminosity-distance formula. In testing the expanding hypothesis, I use the current LCDM formula, which includes the effects of dark energy and dark matter.

 

[elerner]

Peter,

Science is about observations of nature. We can only base science on what is observed or observable. If we find, based on observation, that, at all scales we can observe, GM/r<<c^2, where M is the mass contained in a radius r, then we can conclude that GR is, on large scales, a small correction. If you want to argue that what we believe about parts of the universe that we can't observe determines truth, then you are in the realm of religious faith, not science.

I am not asserting that we have found that inequality to be true on all scales yet. But it is certainly not ruled out either.

 

[Dale]

Expanding universe hypothesis at all scales->

That is not a prediction of the standard LCDM cosmology.

 

[elerner]

Why don't you provide a quotation from and citation of a peer-reviewed published work that backs up your assertion? Since astrophysics is a quantitative science, I also suggest your quotation define what, quantitatively, is a "small" scale excluded from the expanding universe hypothesis. The low-z measurements in my paper are measured on scales of 200-800 Mpc.

In fact you will find that the only scales excluded from the expanding universe hypothesis are those in which matter is gravitationally bound, like clusters of galaxies on scales of one to a few Mpc.

 

[SelfSim]

Hi Eric;

It appears that you may not have considered the impact on angular resolution which results from the dissimilar filters used in the HUDF and Galex datasets(?)
Rather than Hubble resolving objects 1/38 smaller than Galex, our estimation is much more modest at about 5/8.

If you had used the near IR data, instead of NUV (near ultra violet) for the HUDF dataset, the filter wavelength is nearly doubled and HST can now only resolve objects about 1/20 smaller than Galex (instead of the 1/38 you mention).

Did you test the impact this will have and does it alter any of your conclusions?
Cheers

 

[PeterDonis]

If we find, based on observation, that, at all scales we can observe, GM/r<<c^2, where M is the mass contained in a radius r, then we can conclude that GR is, on large scales, a small correction.

No, you can't. You could if you knew a priori that spacetime was static, but you don't know that a priori. FRW spacetimes are examples of non-static spacetimes where, even if the condition you describe holds, the geometry of the spacetime still is not flat spacetime plus "a small correction".

 

[elerner]

Hi SelfSim,
If you read our 2014 paper, we describe that we used the datasets themselves to determine the actual resolutions of the two scopes. In other words, we used the cutoff radius below which the images could not be distinguished from point images--had high stellarity. There was a sharp cutoff for both scopes.

 

[SelfSim]

Hi SelfSim,
If you read our 2014 paper, we describe that we used the datasets themselves to determine the actual resolutions of the two scopes. In other words, we used the cutoff radius below which the images could not be distinguished from point images--had high stellarity. There was a sharp cutoff for both scopes.

Eric;

We understand that part of your methodology, but our query is about the selection of datsets from Galex and HUDF, respectively (as a check).

You say: "To satisfy this condition and properly compare galaxies up to z~5, we have chosen two reference ultraviolet bands, namely the FUV (1550 Å) and NUV (2300 Å) bands as defined by the GALEX satellite, enabling the creation of 8 pairs of samples matched to the HUDF data".

To clarify: Did you use data from the F435W filter? (We've assumed this, as it would be the closest match to the Galex far and near ultraviolet images).

 

[SelfSim]

Others: please bear with me on this query about the 2014 paper .. we believe it has significant bearing on the conclusions of Eric's recent MNRAS paper.

Eric;
These are the cutoff radius results from your 2014 paper,

For GALEX this cutoff is at a radius of 2.4 +/- 0.1 arcsec for galaxies observed in the FUV and 2.6 +/- 0.2 arcsec for galaxies observed in the NUV, while for Hubble this cutoff is at a radius of 0.066 +/- 0.002 arcsec, where the errors are the 1σ statistical uncertainty.

While the Hubble cutoff of 0.066 arcsec compares with a theoretical resolution of 0.05 arcsec using the F435W filter, the Galex result of 2.4 arcsec is 30X higher than the theoretical value of 0.08 arcsec in FUV!

Something appears to be in error here(?)
I suppose it may be possible that the Galex optics were of catastrophically low quality in order to explain this major discrepency however, if this unlikely possibility were so, then also no useful science would be possible.

This discrepency is more likely be due to an error elsewhere .. (?)
Cheers

 

[Dale]

Why don't you provide a quotation from and citation of a peer-reviewed published work that backs up your assertion?

Which assertion, please use the quote feature? That the LCDM model only works at large scales? I already provided 3. More exist, but 3 are sufficient.

 

[elerner]

Self sim,

Not only the 435 filter. For each redshift range, we match the HST filter with either FUV or NUV filter to get the same wavelength band in the rest frames. So we actually have eight separate matched sets. All described in the 2014 paper.

Also on GALEX I guess you used the Dawes formula but it is way off. Look at the GALEX descriptions on their website--the resolution is arcseconds, not a tiny fraction of an arcsecond. Their pixels are much bigger than your value. Why is this?--you have to ask the designers of GALEX. This is just a guess on my part, but GALEX is a survey instrument. If they made the pixels too small, they would end up with too small a field of view, given limits on how big the detector chip can be.

 

[elerner]

Dale, no reference that you have cited supports the assertions you have made. You have said that the expanding universe hypothesis makes no predictions on the scales I have tested it because they are too small. The smallest-scale measurements in my paper cover the range 200-800 Mpc. You need to provide quotes from cited sources that say that these scales are too small to be covered by the expanding universe hypothesis. That is what I am testing. The words" small" and "large" have no meaning unless there is some quantitative comparison.

 

[Dale]

You have said that the expanding universe hypothesis makes no predictions on the scales I have tested

Where did I say that? Use the quote feature and stop claiming I said things that I didn’t.

 

[elerner]

OK, great, just a misunderstanding! Then you agree that my paper is a test of the the expanding universe prediction and that the predictions are contradicted by the data?

 

[Jonathan Scott]

I get the impression that the weakest link in this argument is Tolman's idea that expanding space affects the angular size of more distant objects, which seems to assume a closed curved universe which grows locally with time. I thought this model was now considered misleading, as although comoving coordinates expand, there is no local physical effect of expansion; galaxies are simply moving apart for historical reasons. Tolman has always been one of the great masters of GR, but it seems possible that he missed something. Is there any more recent support for Tolman's conclusions, taking into account alternative universe structure models?

I personally like the analogy of modelling an expanding universe with only 1D of space as a cone made from flat paper, where a circle around the cone represents space and the height from the apex represents time. Although the total amount of space clearly increases with time, it is still flat even on a large scale; there is no local change in scale, and objects moving along parallel paths (including light beams) remain on parallel paths. (This model assumes that the radius of the universe increases uniformly with time, which is obviously another simplification).

[One could similarly assume an even simpler model of a flat disc with radius being time and circumference being space, but for some reason I find the cone picture more interesting].

 

[Dale]

Then you agree that ...

Are you having trouble using the quote feature? Just select the text that I actually wrote and choose “Reply”.

 

[SelfSim]

... Not only the 435 filter. For each redshift range, we match the HST filter with either FUV or NUV filter to get the same wavelength band in the rest frames. So we actually have eight separate matched sets. All described in the 2014 paper.

Also on GALEX I guess you used the Dawes formula but it is way off. Look at the GALEX descriptions on their website--the resolution is arcseconds, not a tiny fraction of an arcsecond. Their pixels are much bigger than your value. Why is this?--you have to ask the designers of GALEX. This is just a guess on my part, but GALEX is a survey instrument. If they made the pixels too small, they would end up with too small a field of view, given limits on how big the detector chip can be.

Eric;

i) The formula we used was the Rayleigh criterion for resolution ... not Dawes
Ie:

ii) The data from the Galex site indicates the pixel size is 1.5 arcseconds which is the angle as “viewed” by each individual pixel and is a measurement for CCD plate scale ... not resolution. The pixel size in arcseconds depends on the focal length of the telescope used.

The physical size of the pixels used by the detector is:

Physical size of pixel (microns) = [(pixel size in arcseconds) X (Focal length)]/206.3

Galex uses a 500mm size telescope at f/6 = 3000mm focal length.
(1.5X3000)/206.3 = 22 microns.

These are not large pixels. By comparison the ACS/WFC camera used by Hubble for the HUDF is 15 micron pixels.

iii) Since you obtained the same result for each HST filter, your calculation for the HUDT data appears to be incorrect due to the wavelength dependence on resolution as per (i) above.

 

[SelfSim]

Oh .. and there is nothing wrong with the Galex optics either, (as I speculated previously - see below for the explanation), which unless Eric can provide alternative explanations, leads us to the conclusion of a calculation error for the HUDT data (Eric - please advise us here).

There is a drop in the off-axis Galex performance, which is a characteristic of the Ritchey-Chretien optical design at lower f/ratios.
(As mentioned in my immediately prior post, Galex uses an f/6 scope).

http://iopscience.iop.org/article/10.1086/520512/pdf:

To verify the fundamental instrument performance from on orbit data, some bright stars were analyzed individually, outside the pipeline. These results show performance that is consistent with or better than what was measured during ground tests. We have also verified the end-to-end performance including the pipeline by stacking images of stars from the MIS survey that were observed at different locations on the detector. The results of these composites are shown in Figures 9 and 10. Performance is reasonably uniform except at the edge of the field, where it is significantly degraded.

Cheers