Disappearance of dark matter since the Big Bang

Answers and Replies

  • #3
Garth
Science Advisor
Gold Member
3,574
105
Note:
Catherine Heymans of the University of Edinburgh describes the research as "a fascinating result", and points out that it is part of a larger effort to reconcile discrepancies (or "tensions") between measurements made by Planck and those from other telescopes. "Other researchers have said that this tension can be resolved if the dark-matter particle is a sterile neutrino," she explains, adding, "others still are looking at different modified-gravity theories to explain the result."

Heymans also points out that the tension could be the result of systematic errors in how one or more of the observations are made. "More data and further meticulous analysis of those data and the systematics that might be associated with them are the way to find out if this fascinating theory could be true," she cautions.
Is it just systematic error, carnivorous Dark Energy, sterile neutrinos or modified gravity?

We wait and see!!

Garth
 
  • #4
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
787
Here's the paper:
http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.113.181301
http://arxiv.org/abs/1406.7297

It's way beyond me, but I'd also love to hear what people think.
Thanks for a specific link! Just noting that the paper you link to is
Indications of a late-time interaction in the dark sector
Valentina Salvatelli, Najla Said, Marco Bruni, Alessandro Melchiorri, David Wands
(Submitted on 27 Jun 2014)
http://inspirehep.net/search?p=find eprint 1406.7297
http://inspirehep.net/search?ln=en&p=refersto:recid:1303847

Beyond me but here is how a later paper placed it in context and perspective, I quote the conclusions section of
http://arxiv.org/abs/arXiv:1410.5832
Banana Split: Testing the Dark Energy Consistency with Geometry and Growth
Eduardo J. Ruiz, Dragan Huterer
(Submitted on 21 Oct 2014)

==quote http://arxiv.org/abs/arXiv:1410.5832 ==
Let us consider possible reasons for the pull of redshift-space distortions toward wgrow > −1. This result is qualitatively not new: a number of recent investigations have already been established that the RSD data are in some conflict with ΛCDM, suggesting less growth at recent times than predicted by the standard model [61].
For example, Beutler et al. [62] have measured a > 2-σ tension in measurements of the growth index γ = 0.772+0.124 −0.097 relative to the ΛCDM (and, for that matter, also wCDM) prediction γ ≃ 0.55.
Similarly, Samushia et al. [48], using DR11 CMASS sample, and the more precise results by Reid et al. [63] that utilized smaller spatial scales by doing extensive halo occupation distribution modeling, have obtained similar results, indicating that growth is suppressed relative to ΛCDM prediction at approximately the 2-σ level.
Moreover, Beutler et al. [64] find a ∼2.5σ evidence for nonzero neutrino mass, again a signature of the hints of the departure from the standard model.
Finally, Salvatelli et al. [65] utilize the combined cosmological probes (including the RSD) in the context of a model where vacuum energy interacts with dark matter, and interpret the results as detection of nonzero interactions between dark matter and dark energy — another possible interpretation of the departure from the standard ΛCDM model.
==endquote==
There's also reference to the Salvatelli et al in this one, coauthored by Roy Maartens
http://arxiv.org/pdf/1409.4933.pdf
In this it is remarked at the outset that "The transfer of energy density between dark energy and dark matter is not ruled out by current observations (for recent work, see e.g. [8–15])" and reference [15] is to Salvatelli et al.


Just for convenience here is the starter physicsworld link, and some others, not necessarily up to date or recommended:
http://physicsworld.com/cws/article/news/2014/nov/18/is-dark-energy-eating-dark-matter
http://physicsworld.com/cws/article/indepth/2010/jun/02/dark-energy-how-the-paradigm-shifted
http://physicsworld.com/cws/article/indepth/2014/jul/10/theories-of-the-dark-side
 
Last edited:

Related Threads on Disappearance of dark matter since the Big Bang

  • Last Post
Replies
3
Views
998
  • Last Post
Replies
21
Views
4K
  • Last Post
Replies
3
Views
806
  • Last Post
Replies
5
Views
1K
Replies
7
Views
3K
  • Last Post
3
Replies
51
Views
9K
  • Last Post
Replies
6
Views
2K
  • Last Post
2
Replies
28
Views
8K
  • Last Post
Replies
6
Views
1K
Replies
5
Views
1K
Top