What Direction Are Galaxies Flowing in the Expanding Universe?

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SUMMARY

The discussion centers on the concept of "dark flow," a proposed bulk motion of galaxies in the expanding universe, primarily based on research by Alexander Kashlinsky and colleagues. Ned Wright's critique of Kashlinsky's 2008 findings emphasizes that the claims of dark flow lack substantial support and contain errors, leading to skepticism within the scientific community. The conversation highlights the importance of relying on academic sources for credible information and suggests that the concept has not gained traction since its introduction. Participants are encouraged to evaluate the citation records of Kashlinsky's publications to assess the validity of the dark flow hypothesis.

PREREQUISITES
  • Understanding of cosmology and extragalactic astrophysics
  • Familiarity with the concept of peculiar velocities in astrophysics
  • Knowledge of academic publication standards and citation metrics
  • Ability to analyze scientific papers and their methodologies
NEXT STEPS
  • Investigate the implications of Kashlinsky's papers on dark flow, particularly arXiv:0910.4958 and arXiv:1001.1261
  • Learn about the methodologies used in measuring large-scale peculiar velocities of galaxies
  • Explore the role of citation analysis in evaluating scientific credibility
  • Review critiques of dark flow and related theories in cosmology
USEFUL FOR

Astronomers, astrophysicists, and students of cosmology who are interested in the dynamics of galaxies and the validity of emerging theories in the field.

WORMHOLE7777
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Anybody out there with info? What part of the expandable universe have the galaxys been observed to be flowing to a pecticular direction. Been looking for information site on topic. Thanks
 
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skepticism about "dark flow" is still advisable.
Here was Ned Wright's comment when Kashlinsky's paper came out:
=quote http://www.astro.ucla.edu/~wright/cosmolog.htm =
Dark Flow Detected - Not!

24 Sep 2008 - Kashlinsky et al. (2008) have claimed a detection of a bulk flow in the motion of many distant X-ray emitting clusters of galaxies. Unfortunately this paper and the companion paper have several errors so their conclusions cannot be trusted. A technical discussion of these errors can be found here.
=endquote=

Only academic sources are to be trusted because they have some self-critical ethic. Popularization and public relations media ("discovery channel") will say unbalanced hype, omitting reservations, and quote scientists' oversimple soundbites, if they think it will excite viewers and boost ratings.

I think if you look at academic sources on "dark flow" (a jazzy name for a possible drift in a large but limited patch of galaxies) you will find it has NOT gained a lot of adherents since 2008. The jury is still out, so to speak. That is my take. But I could be wrong! You can judge for yourself by looking at Kashlinsky's publication record and checking to see how many other people have cited his papers on this alleged drift.

Here are the 4 papers by Kashlinsky that are about the alleged drift. Two in 2008 and then two more around January 2010 with a "new measurement" of the "dark flow".

1. arXiv:1001.1261 [pdf, ps, other]
The error budget of the Dark Flow measurement
F. Atrio-Barandela, A. Kashlinsky, H. Ebeling, D. Kocevski, A. Edge
Comments: ApJ, in press
Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO)

2. arXiv:0910.4958 [pdf, ps, other]
A new measurement of the bulk flow of X-ray luminous clusters of galaxies
A. Kashlinsky (GSFC), F. Atrio-Barandela (U Salamanca, Spain), H. Ebeling (IfA, Hawaii), A. Edge (U of Durham, UK), D. Kocevski (UCD)
Comments: Ap.J. (Letters), Mar 20/2010. Replaced with published version
Journal-ref: ApJ, (2010), 712, L81-l85
Subjects: Cosmology and Extragalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph)

5. arXiv:0809.3734 [pdf, ps, other]
A measurement of large-scale peculiar velocities of clusters of galaxies: results and cosmological implications
A. Kashlinsky (GSFC), F. Atrio-Barandela (U of Salamanca), D. Kocevski (UC Davis), H. Ebeling (U of Hawaii)
Comments: Ap.J. (Letters), in press. 20 Oct issue (Vol. 686)
Subjects: Astrophysics (astro-ph)

6. arXiv:0809.3733 [pdf, ps, other]
A measurement of large-scale peculiar velocities of clusters of galaxies: technical details
A. Kashlinsky (GSFC), F. Atrio-Barandela (U of Salamanca), D. Kocevski (UC Davis), H. Ebeling (U of Hawaii)
Comments: Minor changes to match the published version - Ap.J., 1 Feb 2009 issue
Subjects: Astrophysics (astro-ph)

Here is the list of all his publications with live links to the PDF (and the html summaries called "abstracts")
http://arxiv.org/find/grp_physics/1/au:+kashlinsky/0/1/0/all/0/1

You have to judge for yourself. A key factor is the "cited by" link on the HTML abstract page. You can see how many other scientists have cited his two recent "dark flow" papers: the "new measurement" one labeled 0910.4958 and the "error budget" one labeled 1001.1261
If there is a big dropoff in citations, then probably the scientific community is not buying it. If citations remain high then there is a chance the idea is going somewhere (other than out into the popular media.)
 
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I second that motion, marcus. Bold claims require bold evidence. The OP needs citations to assert this claim.
 

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