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Alternative Cosmology Group Newsletter - June 2006
Posted July 5, 2006
This has been an interesting month for cosmology, so this
newsletter is more extensive than usual.
Hubble relationship
The most striking result is the claim that a laboratory
experiment has measured directly the expansion of space, or
rather the lack of such expansion.
The exclusion of WMAP's Hubble constant by laser interferometry
Authors: Richard Lieu, Don A. Gregory
http://www.arxiv.org/abs/astro-ph?papernum=.+0605611
In other developments bearing on the Hubble relationship,
measurements of Gamma ray bursters are used to claim a close
agreement at high z with the conventional luminosity formula.
(However the results are indistinguishable from the predictions
of a non-expanding universe with z proportional to distance.)
The Hubble diagram extended to z>>1: the gamma-ray properties of
GRBs confirm the Lambda-CDM model
Authors: C. Firmani (1,2), V. Avila-Reese (2), G. Ghisellini
(1), G. Ghirlanda (1) ((1) Osserv. Astron. di Brera, Italy; (2)
Instituto de Astronomia, U.N.A.M., Mexico)
http://www.arxiv.org/abs/astro-ph?papernum=.+0605430
Plasma–based explanation of the Hubble relation and surface brightness of galaxies.
Surface brightness in plasma-redshift cosmology
Authors: Ari Brynjolfsson
http://www.arxiv.org/abs/astro-ph?papernum=.+0605599
A review of redshift periodicities determines that they are
statistically significant.
On the investigations of galaxy redshift periodicity
Authors: K. Bajan, P. Flin, W. Godlowski, V.P. Pervushin, to be
published in Part. and Nucl. Lett. 2006
Metallicity evolution
Two papers indicate that metallicity, at least for a given
galaxy size, seems not to have changed with redshift.
High Redshift Intergalactic C IV Abundance Measurements from the
Near-Infrared Spectra of Two z~6 QSOs
Authors: Robert A. Simcoe (MIT)
http://www.arxiv.org/abs/astro-ph?papernum=0605710
Velocity-Metallicity Correlation for high-z DLA Galaxies:
Evidence for a Mass-Metallicity Relation?
Authors: C. Ledoux, P. Petitjean, J.P.U. Fynbo, P. Moller, R.
Srianand
A&A in press
http://www.arxiv.org/abs/astro-ph?papernum=0606185
Reionization problems
The observed amount of UV radiation is insufficient at high-z to
maintain observed ionization, if the density of gas is as high
as predicted by Big Bang theory.
Keck Deep Fields. III. Luminosity-dependent Evolution of the
Ultraviolet Luminosity and Star Formation Rate Densities at z~4,
3, and 2
Authors: Marcin Sawicki, David Thompson
Accepted for publication in the Astrophysical Journal.
http://www.arxiv.org/abs/astro-ph?papernum=0605406
This difficulty may be compounded by observations of the large
amount of dust produced by supernovae, further reducing UV
output.
Massive-Star Supernovae as Major Dust Factories
Authors: Ben E. K. Sugerman, Barbara Ercolano, M. J. Barlow, A.
G. G. M. Tielens, Geoffrey C. Clayton, Albert A. Zijlstra,
Margaret Meixner, Angela Speck, Tim M. Gledhill, Nino Panagia,
Martin Cohen, Karl D. Gordon, Martin Meyer, Joanna Fabbri, J. E.
Bowey, Douglas L. Welch, Michael W. Regan, Robert C. Kennicutt,
Jr
Published in 2006 Jun 8 edition of Science Express
http://www.arxiv.org/abs/astro-ph?papernum=0606132
Difficulties explaining Lithium 6 observations
Population III Generated Cosmic Rays and the Production of Li6
Authors: Emmanuel Rollinde, Elisabeth Vangioni, Keith A. Olive
http://www.arxiv.org/abs/astro-ph?papernum=0605633
Can Galactic Cosmic Rays Account for Solar 6Li Without
Overproducing Gamma Rays?
Authors: T. Prodanovic, B. D. Fields
To be published in ApJL
http://www.arxiv.org/abs/astro-ph?papernum=+0605675
Rotation curves/dark matter
Observations indicate that the Milky Ways’ spiral arms extend
out father than can be explained with conventional gravitational
models, indicating the need to take into account magnetic
fields, additional sources of matter or MOND.
The Spiral Structure of the Outer Milky Way in Hydrogen
Authors: E.S. Levine, Leo Blitz, Carl Heiles
Accepted for publication in Science.
http://www.arxiv.org/abs/astro-ph?papernum=0605728
Stars in the Galaxy’s out halo appear to have very high M/L
ratios, explaining some of the “dark matter”
The Red Halo Phenomenon
Authors: E. Zackrisson, N. Bergvall, G. Ostlin, G. Micheva, M.
Leksell
Accepted for publication in ApJ
http://www.arxiv.org/abs/astro-ph?papernum=0606218
Review of MOND
Observational Constraints on the Acceleration Discrepancy
Problem
Authors: Stacy McGaugh (University of Maryland)
Comments: 55 pages (all figures). Annotated slides from invited
review for the Alternative Gravities & Dark Matter Workshop
http://www.arxiv.org/abs/astro-ph/0606351
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