500 Mpc by 1200 Mpc Galactic Cluster!

[Robert L. Oldershaw]

I am surprised that no one at SAR has called attention to the following discovery.

http://news.sciencemag.org/sciencenow/2013/01/scienceshot-the-largest-structur.html?ref=hp

Let the hand-waving begin.

Robert L. Oldershaw
Discrete Scale Relativity
http://www3.amherst.edu/~rloldershaw

[Eric Gisse]

On Sunday, January 13, 2013 1:11:45 AM UTC-6, Robert L. Oldershaw wrote:
> I am surprised that no one at SAR has called attention to the following discovery.
>
> http://news.sciencemag.org/sciencenow/2013/01/scienceshot-the-largest-structur.html?ref=hp
>
> Let the hand-waving begin.

I take it from this comment you have a satisfying explanation for the observation?

[Mod. note: satisfying and, ideally, suitable for posting here -- mjh]

[Robert L. Oldershaw]

On Tuesday, January 15, 2013 4:10:30 AM UTC-5, Eric Gisse wrote:
>
> I take it from this comment you have a satisfying explanation for the observation?
>
> [Mod. note: satisfying and, ideally, suitable for posting here -- mjh]

-------------------------------------------------

1. Assumptions are double-edged swords.

2. Given the well-known problems with LCDM, e.g., http://arxiv.org/abs/1301.0623 , this vast galaxy cluster, exceeding LCDM limits, should give one added reason to question the aging and failing conventional cosmological paradigm.

3. Almost certainly we will be going to an inhomogeneous paradigm in the future.

4. I have my favorite class of inhomogeneous models, but this is clearly not the venue to discuss that.

5. Dinner is ready.

6. Take it from here and any way you like it.

[Eric Gisse]

On Wednesday, January 16, 2013 1:44:03 AM UTC-6, Robert L. Oldershaw wrote:
> On Tuesday, January 15, 2013 4:10:30 AM UTC-5, Eric Gisse wrote:
> > I take it from this comment you have a satisfying explanation for the observation?
>

> 1. Assumptions are double-edged swords.

No, then?

I'm not really keen on bringing in more numerology however you haven't
posted for a long time so I was curious to know if you had an answer
for the various technical challenges... ;)

> 2. Given the well-known problems with LCDM, e.g.,
> http://arxiv.org/abs/1301.0623 , this vast galaxy cluster, exceeding
> LCDM limits, should give one added reason to question the aging and
> failing conventional cosmological paradigm.

MOND? C'mon.

MOND has been falsified repeatedly and conclusively. Its' only value
is in the curiosity in that it is successful in certain situations. It
does not work at large or small scales, and gets the third CMB peak
wrong. Relativistic adaptations are yet to be successful, and dark
matter wins the battle of "what makes more sense" rather handily.

LCDM's galactic scale issues appear to be more strongly related to
quality of observation than being grossly wrong. It has been only
extremely recently that we were able to falsify spherically symmetric
models of dark matter halos and even that was only for the Milky Way.

Finding a structure at that length scale is neat, however that does
not mean it is gravitationally bound. Is it? The article isn't clear.

I also note that the MNRAS article uses a lot of statistical analysis.
You have routinely rejected a very large amount of evidence that you
do not like because math was used in analyzing the data. Do you concur
with the analysis, or is the result all that interests you here?

What is less clear is "what does this mean?" Say there are some large
scale inhomogeneities in the universe. So what? The cosmological
approximation of homogeneity has to fail somewhere (something I hope
is self evident), and the necessity of it to begin with isn't
something that I can fully articulate.

The article does mention some challenges to homogeneity through the
CMB however to my knowledge none of those challenges have yet survived
technical review. Too much reading of Komatsu on the subject has made
me skeptical.

[Mod. note: quoted text trimmed -- mjh]

[Robert L. Oldershaw]

On Wednesday, January 16, 2013 4:18:36 PM UTC-5, Eric Gisse wrote:
>
> MOND? C'mon.
>

I have almost no interest in "MOND".
See what I mean about assumptions?

>
> LCDM's galactic scale issues appear to be more strongly related to
> quality of observation than being grossly wrong. It has been only
>

Well, for starters: the lack of thousands of dark matter "subhalos"
per galaxy is a serious problem, the cored nature of galactic dark
matter distributions is a serious problem, and the 40-year failure to
find a shred of empirical evidence for any form of CDM ("WIMPs,
axions, sterile neutrinos, whatever-ons,...) is a serious problem.

These three well-known problems, and there are definitely more, are in
serious conflict with the LCDM model, and they cannot be hand-waved
away as anecdotal or due to the "quality" of the observations.

Cheerio,
Robert L. Oldershaw
Fractal Cosmology

"How can physics live up to its true greatness except by a new
revolution in outlook which dwarfs all its past revolutions? And when
it comes, will we not say to each other, 'Oh, how beautiful and simple
it all is! How could we ever have missed it for so long!'." John
Archibald Wheeler

[jacob navia]

Le 15/01/13 10:10, Eric Gisse a �crit :

Mr Giese

As far as I remember the sentence:

"The Universe is homogeneous at large scales"

has been repeated like a mantra since years and years.

Apparently, it is NOT.

An object spanning 4 billion years means the universe is NOT homogeneous
at large scales at all.

Obviously you can put this away with:

"4 000 000 000 light years is not large"

or even

"Doesn't matter. It is an exception but in larger scales it is smooth"

What is interesting is that a new method was needed to get to this
gargantuan object. Probably, once the method is perfected, we will find
more of those or even bigger ones.

jacob

[Eric Gisse]

On Friday, January 18, 2013 1:48:36 AM UTC-6, jacob navia wrote:
> Le 15/01/13 10:10, Eric Gisse a �crit :
>
> > On Sunday, January 13, 2013 1:11:45 AM UTC-6, Robert L. Oldershaw wrote:
>
> >> I am surprised that no one at SAR has called attention to the following discovery.
>
> >>
>
> >> http://news.sciencemag.org/sciencenow/2013/01/scienceshot-the-largest-structur.html?ref=hp
>
> >>
>
> >> Let the hand-waving begin.
>
> >
>
> > I take it from this comment you have a satisfying explanation for the observation?
>
> >
>
> > [Mod. note: satisfying and, ideally, suitable for posting here -- mjh]
>
> >
>
>
>
> Mr Giese
>
>
>
> As far as I remember the sentence:
>
>
>
> "The Universe is homogeneous at large scales"
>
>
>
> has been repeated like a mantra since years and years.

Peel off the dipole moment in the CMBR and you see that the universe was perfectly homogeneous to a parts-per-million level.

>
>
>
> Apparently, it is NOT.

Of course it isn't. This tells us nothing new.

The only role homogeneity has in cosmological discussions is the intersection with the inhomogeneities in the CMB and how it ties into inflation.

>
>
>
> An object spanning 4 billion years means the universe is NOT homogeneous
>
> at large scales at all.

The question "is the universe homogeneous?" is a stupid and uninteresting question because it obviously isn't if you look outside.

What is more interesting and not stupid is asking for a quantitative measurement of the inhomogeneity and seeing how close it /is/ to perfectly homogeneous.

>
>
>
> Obviously you can put this away with:
>
>
>
> "4 000 000 000 light years is not large"

Well, it is.

z ~ 1 is not that far in the past.

>
>
>
> or even
>
>
>
> "Doesn't matter. It is an exception but in larger scales it is smooth"

This might actually be a valid argument.

Shifting gears to a different scale...

I found an interesting lesson in the discussion of what would constitute a violation of homogeneity of the CMB. Specifically, if one takes a deep look at the inhomogeneities you occasionally find something "odd".

The takehome lesson was that even though you can occasionally find an unusual correlation in the CMB, it is /still permissible/ under the same notion that it is perfectly possible albeit improbable that you can get heads if you flip a coin 20 times in a row.

We are integrating observations over the whole bulk of the universe. There's a lot of coinflips.

The question then starts to shift to a more subtle question of "is the supposed violation we are seeing statistically significant?"

Even if we take it at face value that this is a gravitationally bound object rather than a group of objects that are temporarily close, it may very well be the case that anomalies like this are permissible.

This is a question that USENET jockeying cannot easily answer, regardless of how much nicer it'd be if there were simple, definitive answers.

>
>
>
> What is interesting is that a new method was needed to get to this
>
> gargantuan object. Probably, once the method is perfected, we will find
>
> more of those or even bigger ones.

Perhaps!

I'm not even certain that this is a problem.

We don't have the ability to spin up another universe to test our theories, but we can run simulations.

Take a look at the Millennium 2 simulation:

http://www.mpa-garching.mpg.de/galform/millennium-II/Images/evol_12panel.jpg

The exact answer for what you see depends on h (which is ~0.7 in reality), but you can get a reasonably good idea of what the concordance cosmology would look like using the results of that simulation.

What do we see? Filamentary structures spanning the whole universe, which grow more distinct as time evolves.

Perhaps this is an example of such a structure?

>
>
>
> jacob

[Nicolaas Vroom]

Op zondag 20 januari 2013 10:03:41 UTC+1 schreef Eric Gisse het volgende:

> I'm not even certain that this is a problem.
> We don't have the ability to spin up another universe to test
> our theories, but we can run simulations.
> Take a look at the Millennium 2 simulation:
> http://www.mpa-garching.mpg.de/galform/millennium-II/Images/evol_12panel.jpg
> The exact answer for what you see depends on h (which is ~0.7 in reality),
> but you can get a reasonably good idea of what the concordance cosmology
> would look like using the results of that simulation.
> What do we see? Filamentary structures spanning the whole universe,
> which grow more distinct as time evolves.
> Perhaps this is an example of such a structure?

The question is: Is our Universe homogeneous (and isotrophic)
The reason of this question is the following article:
http://mnras.oxfordjournals.org/content/early/2013/01/07/mnras.sts497.full#sec-5
When you goto
http://www.nature.com/nature/journal/v490/n7419_supp/full/490S2a.html
and you study figure 1 than you will see the evolution of the Universe
going from left to right. The present is on the right.
Our nearest active Quasar is 3C 273 2.4 billion ly away. That means on the right part of figure 1 there are almost no quasars.
The question boils down to the issue: Is the mass (density) in vertical direction (same period) everywhere the same.
The problem is: what we see (observe) is always in the past.
Figure 8 in: http://users.telenet.be/nicvroom/friedmann%27s%20equation.htm#Q3
shows the path of a lightray which started close to the BigBang.
The right side shows the present. What Figure 8 shows is that at present
we can only see a very small part of the total Universe.
That means that it is very difficult to quantify how homogeneous the
Universe at present is. A simulation of the evolution of the Universe is of no much help.
The same IMO is also true for the past.

Nicolaas Vroom