Arcadian Functor

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Marni D. Sheppeard

Thursday, September 25, 2008

The Dark Side IV

If you thought the Dark Force had thrown enough mysteries into standard cosmology, think again! Now there is a Dark Flow, seen as a remarkable motion of 700 galaxy clusters over a scale of 6 billion light years, as indicated by WMAP data. It appears that $\Lambda$CDM, as valiantly as it has tried to keep up with developments, may finally bite the dust. The motion is being touted as a gravitational pull from matter beyond our horizon. Enough of this rubbish.

Hat tip: Mottle. See the NASA news. And here is Louise's post.

9 Comments:

Blogger Matti Pitkanen said...

The presence of the attractor outside the visible universe conforms with the notion of manysheeted space-time predicting also a manysheeted cosmology.

This means a hierarchy of space-time sheets: those with varying p-adic length scale and those labelled by various values of Planck constants at pages of book like structure obtained by gluing together singular coverings and factor spaces of 8-D imbedding space (roughly). Particles at different pages are dark relative to each other in the sense that there are no local interaction vertices: classical interactions and those by exchanges of say photons are possible.

Each sheet in many-sheeted cosmology has different horizon size. The attractor would correspond to a different value of Planck constant and have larger horizon size. Dark energy would be dark matter and the phase transitions increasing Planck constant would induce phases of accelerated expansion. In average sense these periods would give ordinary cosmology without accelerated expansion.

September 25, 2008 4:27 PM  
Blogger Kea said...

Hi Matti. Yes, I appreciate this point of view, but I suspect that it isn't what they had in mind when they used the words beyond the horizon. No doubt they envisage a single Planck scale.

September 25, 2008 4:41 PM  
Blogger L. Riofrio said...

I think the LCDM is a dead issue among scientists. Study of "dark energy" now encompasses divergent ideas like modifications to gravity. Perhaps the mainstream media will notice the death of LCDM next.

September 26, 2008 1:15 AM  
Blogger Kea said...

Actually, Louise, people are seriously (believe it or not) suggesting that inflation predicted this.

September 26, 2008 9:02 AM  
Blogger CarlBrannen said...

I'm getting relatively large reading on the subject of dark flow and the speed of gravity. What's odder is that people are actually clicking the links to other ideas.

September 27, 2008 8:06 AM  
Blogger Kea said...

Carl, there must be some intelligent physicists who are smart enough to realise the issues this raises for the standard model - meaning The standard model.

September 27, 2008 8:23 AM  
Blogger Matti Pitkanen said...

Dear Kea,

well...! My understanding is that precisely this is what they mean. In standard cosmology no large scale motions in scales larger than horizon should exist.

Just a little loosely related comment inspired by a later posting of Lubos about 1/hbar proportionality of formulas for black hole entropy. This proportionality reflects the basic thermodynamical implication of quantization: the phase space of N-dimensional system decomposes into cells of volume hbar^N. If hbar becomes large and gigantic as it would in the case of gravitation (hbar= GM1M2/v0, v_0/c= 2^(-11)) this means that blackhole entropy is extremely small. Black is dark;-) as I realized for few years ago, and it would be interesting to consider the consequences.

Heat death is believed by standard physicists to be waiting for all forms of life. We would live in the silliest possible Universe. I cannot believe this. I am ready to admit that some of our theories about the Universe are really silly, but entire Universe?-No!

The hierarchy of Planck constants would indeed make Universe intelligent. For instance, if the rate for the reduction of temperature is proportional to 1/hbar -as looks natural- then there is always an infinite number of hierarchy levels for which temperature is above a given temperature since the temperature at these pages is reduced so slowly.

Life can leak to the pages of big book labelled by larger values of Planck constant without breaking second law since the scaling of the size of the system by hbar increases phase space volume and keeps entropy constant. Evolution by quantum leaps increasing hbar increasing the time scale of planned action and long term memory is another manner to say this.

The observed dark flow might be seen as a direct support for this more optimistic view about Life and the Universe and Everything;-).

September 27, 2008 3:28 PM  
Anonymous Alberto G.P. said...

Kea,

You wrote,

"\Lambda$CDM, as valiantly as it has tried to keep up with developments, may finally bite the dust. The motion is being touted as a gravitational pull from matter beyond our horizon. Enough of this rubbish."

Well, if you accept that it has been found a weakness in the Lambda-CDM model, why can't you admit that scale-invariant spectrum of primordial perturbations is wrong, too?, As The Universe can be much more bigger than the visible portion and nobody knows that there is beyond of visible horizon then could exist a gravitational pull induced by the matter placed beyond.

The Best.

September 28, 2008 7:37 AM  
Blogger Kea said...

Welcome, Alberto. I confess to loudly professing my own prejudices when I poo hoo this mainstream way of looking at things.

September 28, 2008 7:40 AM  

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