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Fraser
2008-Oct-12, 03:40 AM
A few weeks ago, researchers announced the discovery of a "dark flow" of invisible matter tugging at distant galaxy clusters at the edge of the universe. Now comes more evidence of unseen and unknown forces in the cosmos, but this time its closer to home. A group of researchers have discovered that [...]

More... (http://www.universetoday.com/2008/10/11/the-universe-is-not-expanding-uniformly/)

Seiryuu
2008-Oct-12, 10:25 AM
Interesting! ^^

Jerry
2008-Oct-12, 02:57 PM
This is getting really silly now! This makes no more sense than concluding that the 'fingers of god' effect is exactly that. An Occum's razor approach should conclude that there is an unexpected systemic error in data, not a 'taffy force'.

trinitree88
2008-Oct-12, 04:43 PM
A few weeks ago, researchers announced the discovery of a "dark flow" of invisible matter tugging at distant galaxy clusters at the edge of the universe. Now comes more evidence of unseen and unknown forces in the cosmos, but this time its closer to home. A group of researchers have discovered that [...]

More... (http://www.universetoday.com/2008/10/11/the-universe-is-not-expanding-uniformly/)

Fraser. This is not the the only recent piece of evidence of large scale structure or flows in the universe. The recent survey of 355 quasars indicated that their group polarizations also indicate evidence of a coherent symmetry. In view of the fact that physics at the highest energies and temperatures is dominated by weak currents from the predominantly neutrinos that are involved involved, and that these currents all demonstrate axisymmetric parity effects if any magnetic fields are involved, then it would be surprising if the Big Bang cosmology was not going to find a preferential direction of expansion, even late after the initial expansion. To not find this would imply a perfect symmetry in the original fireball, something not seen in supernovae remnants.
It will be interesting to see if it shows in the WMAP data. see:http://arxiv.org/abs/astro-ph/0507274

Jerry
2008-Oct-12, 05:16 PM
It will be interesting to see if it shows in the WMAP data. see:http://arxiv.org/abs/astro-ph/0507274
???
Isn't one of the main point of this paper that the near-local vector in galaxy vectors is much to great when it is contrasted with to the local vector of the CMB as measured by the WMAP probe?


A flow of this amplitude on such a large scale is not expected in theWMAP5-normalized {alpha}CDM cosmology. The observed bulk flow favors the upper values of the WMAP5[directional{?}] error-ellipse, but even the point at the top of the WMAP5 95% confidence ellipse predicts a bulk flow which is too small compared to that observed at a confidence level > 98%...

To reiterate, the results presented in this paper pose a challenge to the standard {alpha}CDM model with the WMAP5 parameters.

Ozzy
2008-Oct-13, 08:49 AM
Please bear with my ignorance. I'm just trying to get a handle on this.

Is a "dark flow" like a river of invisible matter, or is this referring to a lop-sided concentration? (or something else entirely?)


An increase in density "pulls' some galaxies through space faster than would normally be expected?


From Jerry
An Occum's razor approach should conclude that there is an unexpected systemic error in data, not a 'taffy force'.

The dark flow hypothesis is an incorrect interpretation, or the data it based on is faulty?

trinitree88
2008-Oct-13, 07:06 PM
???
Isn't one of the main point of this paper that the near-local vector in galaxy vectors is much to great when it is contrasted with to the local vector of the CMB as measured by the WMAP probe?

Jerry. Yup. I'd like to see it in a graphic display. It's so much easier to visualize when the data has a picture...kind of like seeing wind velocities on a weather map as vectors...gives you a physical feel for the pressure gradient. pete

sohh_fly
2008-Oct-14, 01:59 AM
maybe that part of the sky is being tugged along ,so the part that is behind is being dragged, something unseen changes perception

WaxRubiks
2008-Oct-14, 04:41 AM
I had this ATM idea that expansion was caused because the Universe was trying to become flat due to discrepancies in space-time volume, in a hypersphere, caused by the warp due to matter. That is, like the circle on a 2-sphere would encompass more area than the circumference would suggest.
If that were true, there would be more expansion where there were more matter....I s'pose...

ETA: more atm- maybe matter is brought about by this descrepency......