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trinitree88
2010-Jun-25, 07:09 PM
Eric Linder gives an argument for the uniqueness of our time in our galaxy in the universe. And I thought we were special because the CMB is aligned with the solar system at ~ 9 sigma.


SEE:http://arxiv.org/PS_cache/arxiv/pdf/1006/1006.4632v1.pdf

danscope
2010-Jun-27, 08:37 PM
Hi, Does this suggest that "everything" is accelerating? And do they have a common vector?
Best regards,
Dan

Jerry
2010-Jun-27, 11:40 PM
It is silly. So is this paper:

http://arxiv.org/abs/1006.4630



These values are fully consistent with predictions for a WMAP7--normalised LCDM Universe and inconsistent (at >5 sigma) with a Dvali-Gabadadze-Porrati (DGP) model for the Universe. We can convert the units of these sigma_v measurements to 270^{+40}_{-41} km/s and 320^{+41}_{-41} km/s respectively (assuming a LCDM universe), which are much lower than that expected based on recent low redshift (z<0.2) measurements of the peculiar velocity field (or ``bulk flows"), i.e., we would have predicted motions of ~ 600 km/s over our redshift range (0.16<z<0.47) to be consistent with these local measurements. One possible explanation for such a large discrepancy is that our Galaxy is located in unusually over, or under, dense region of the Universe.

'fully consistent with WMAP; but requiring a large discrepancy within our own galaxy'? Linder is telling us we are in a special time, and Song is telling us we are in a special place, and they are both using WMAP to prove it.

WMAP is not an anchor we can build cosmology about and define everything that doesn't fit as a 'special time' or a local fluke. We are local. We can't assume we are in a special time or a special place without throwing out the first law of science: We assume all that we see has a causal root. No magic times, and no magic places.

whimsyfree
2010-Jun-28, 08:24 AM
ArXiv papers that haven't been accepted to a peer reviewed journal aren't worth a pinch of salt.

Nereid
2010-Jun-28, 03:22 PM
ArXiv papers that haven't been accepted to a peer reviewed journal aren't worth a pinch of salt.
In my experience, it depends on the track record of the authors, and the journal they're submitting to.

It is certainly true that there are, nearly always, some changes made between the v1 arXiv preprint and what finally appears in a peer-reviewed journal. However, many authors have a pretty good track record of having their preprints accepted for publication with only minor, or even trivial, edits.

whimsyfree
2010-Jul-13, 01:21 AM
In my experience, it depends on the track record of the authors, and the journal they're submitting to.

It is certainly true that there are, nearly always, some changes made between the v1 arXiv preprint and what finally appears in a peer-reviewed journal. However, many authors have a pretty good track record of having their preprints accepted for publication with only minor, or even trivial, edits.

Obviously if you know the authors by reputation it's different. I was referring to papers by unknown authors. There's all sorts of nonsense on arXiv.