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Cosmology
in 2007: A Year-End Survey
By
Eric J. Lerner
In the past year, evidence again the conventional Big Bang model built up
on several fronts. The
evidence that the cosmic background radiation (CBR) is not randomly spread
across the sky, as the inflationary Big Bang predicts, has become
overwhelming. The contradictions between Big Bang predictions of the
abundance of light elements and observations continue to get worse. In
addition, new observations have contradicted the conventional concept of a
universe that is homogenous and isotropic, demonstrating alignments of
galaxies on extremely large scales.
Unfortunately, the accumulation of evidence hasn’t yet sparked a general
debate in cosmology over whether the Big Bang model is a valid one. But
there are a few small signs that there is beginning to be a greater
openness to questioning at least some aspects of the “convergence
cosmology” and its ever-growing grab-bag of hypothetical constructs,
like inflation, dark matter, dark energy, and quintessence.
As conventional cosmologists leap ever higher into the realms of
fantasy, even the popular press is starting, ever-so tentatively, to
wonder if the Emperor really is naked.
1. Problems mount with the Big Bang
A. Patterns in the CBR become indisputable
The hypothetical process of “inflation” is a crucial part of the
current Big Bang model. Without this early period of super-fast expansion,
the theory predicts that different parts of the sky should have widely
differing intensities of the CBR, in contradiction to observations. While
inflation is a purely ad-hoc hypothetical process, based on no known laws
of physics, it does make one firm prediction. This is that the small
anisotropies or fluctuations in the CBR should be distributed entirely
randomly—in a Gaussian distribution.
Yet almost since the first results of the WMAP satellite were released
four years ago, it has been clear that the small anisotropies in the CBR
are not random, there are patterns. Especially at large angular sale in
the sky, there are regions where the CBR is smoother and where it is
lumpier. In addition there
are too many “hot” and “cold” spots in the sky for a Gaussian
distribution.
There have been a number of efforts to try to attribute this
non-randomness to a limited section of the sky which is “anomalous”
and in particular to the “WMAP cold spot” a region of the sky with the
least intense CBR. Lawrence Rudnick et al published a widely noted paper
in which they tried to attribute the cold spot to a huge void, 280 Mpc in
diameter, that has been observed in the distribution of radio galaxies.
The idea was that the gravitational effects of such a void could slightly
redshift CBR photons from that direction.
However, Pavel Naselsky
et al, among others demonstrated statistically that the non-Gaussian
patterns on the sky are not just limited to the Cold Spot. Aleksandar
Rakic, and Dominik J. Schwarz showed convincingly that the patterns are
incompatible with the hypothesis of Guassianity, and Amit Yadav and
Benajmin Wandelt, using a different method of analysis, ruled out the
inflationary prediction at the 99.5% confidence level. The hot and cold
spots themselves are not circular and show alignments on the sky as P.
Vielva et al demonstrate.
Despite all this contradictory evidence, in only one paper, that of Y.
Wiaux et al, is the validity of the inflationary hypothesis explicitly
questioned. By contrast, Yadav and Wandelt conclude, not that the
inflationary theory is wrong, but only that it is too simple and that more
“exotic theories” with “multiple scalar fields, features in
inflation potential, non-adiabatic fluctuations, non-canonical kinetic
terms, deviations from the Bunch-Davies vacuum” will be needed.
To complicate the picture further, Gerrit L Verschuur finds that much of
the anisotropy correlates with plasma clouds within the Milky Way,
although the statistical significance of these correlations is still in
some dispute.
Extragalactic Radio Sources and the WMAP Cold Spot
Authors:
Lawrence Rudnick, Shea Brown, Liliya R. Williams
http://arxiv.org/abs/0704.0908v1
The mystery of the WMAP cold spot
Authors:
Pave D. Naselsky (1), Per Rex Christensen (1), Peter Coles (2), Oleg
Verkhodanov (3), Dmitry Novikov (4,5), Jaiseung Kim (1) ((1) Niels Bohr
Institute, Copenhagen, Denmark; (2) School of Physics and Astronomy,
Cardiff University, Wales, United Kingdom; (3) Special astrophysical
observatory, Nizhnij Arkhyz, Russia; (4) Imperial College, London, United
Kingdom; (5) AstroSpace Center of Lebedev Physical Institute, Moscow,
Russia)
arXiv:0712.1118v1
[astro-ph]
Correlating anomalies of the microwave sky: The Good, the Evil and the
Axis
Authors:
Aleksandar Rakic, and Dominik J. Schwarz
http://arxiv.org/abs/astro-ph/0703266v2
P. Vielva, Y. Wiaux, E. Martinez, P. Vandergheynst:
Alignment and signed-intensity anomalies in WMAP data (MNRAS 000, 1 - 12,
2007)
arxiv:
0704:3736v2
Non-Guassianity analysis on local morphological measures of WMAP data
Authors:
Y. Wiaux, P. Vielva, R. B. Barreiro, E. Martinez-Gonzalez, P.
Vandergheynst
arXiv:0706.2346v1
[astro-ph]
Detection of primordial non-Gaussianity (fNL) in the WMAP 3-year data at
above 99.5% confidence
Authors:
Amit P. S. Yadav, Benjamin D. Wandelt
arXiv:0712.1148v2
[astro-ph]
High Galactic Latitude Interstellar Neutral Hydrogen Structure and
Associated (WMAP) High Frequency Continuum Emission
Author:
Gerrit L. Verschuur
arXiv:0704.1125v2
[astro-ph]
B.
SZ anomaly raises questions of the nature of the CBR
In the conventional cosmology, the CBR is assumed to come from vast
distances corresponding to the early years after the Big Bang. As a result
it is expected that dense clouds of plasma in clusters of galaxies will
cast slight shadows by the CBR radiation coming from beyond them. This
shadowing effect is called the Sunyaev-Zeldovich effect. In 2006 Richard
Lieu et al pointed out that the shadowing effect was much less than was
expected, implying that the CBR originated between us and the clusters,
not beyond them. In 2007, Bailey and Shanks extended this analysis to many
more clusters than the 31 studied by Lieu. They found that not only was
the SZ effect less than expected, it tended to disappear as the redshift
of the clusters studied went from 0.1 to 0.3, implying that most of the
CBR come from redshifts less than 0.3. The authors did not draw that
conclusion. But they did show that there was no available conventional
explanation of the results.
Anomalous SZ Contribution to 3 Year WMAP Data
Authors:
R.M. Bielby, T. Shanks
http://arxiv.org/abs/astro-ph/0703470v1
C.
Light elements prediction in further conflict with observation
A second key prediction of the Big Bang model is the abundance of
certain light isotopes deuterium He-3, He-4 and Li-7. In particular, the
Big Bang is supposed to have produce almost exactly 25% He as compared
with hydrogen.
However, in an important paper that has received almost no notice although
it was posted on the ArXiv in March, 2007 and published in MNRAS in
December, Luca Casagrande et al show that old main sequence stars have
much less helium than Big Bang nucleosynthesis predicts. Since He-4 is
produced by stars, they should have more helium, not less, than the Big
Bang predictions. The ones with the least helium are the ones that have
the least heavier elements, which all astronomers agree are formed in
stars and then distributed into interstellar space, going on to be
incorporated in other stars. If helium abundance rises with heavy element
abundance from values well below the primordial one, it implies that the
helium, as well as the heavier elements, is formed in ordinary stars early
in the process of forming a galaxy. This is exactly what a number of
researchers, including myself, have hypothesized as the origin of the
so-called primordial helium.
Casagrande et al found that for stars that had a metal (heavy element
content) of less than 1.3%, the average helium abundance was 18+2%,
three standard deviations below the Big Bang predictions.
For individual stars the situation was even worse. The star in the
sample with the fourth lowest metallicity, 0.14% (8%
of the solar value), thus presumably the fourth oldest, had a helium
abundance of 13+2% or six sigma below the predicted value. Two
other individual stars had helium content more than four sigma below the
predicted value, including one with a helium abundance of only 9.5+3.2%,
less than half the predicted value.
However, Casagrande et al do not draw the conclusion that this data tends
to refute the Big Bang theory. While they carefully rule out any
explanation due to problems in stellar theory or their measurements, they
conclude that there must be an unknown problem in the data. One caution
about this data is that the helium is measured indirectly using stellar
theory. However, the theory
is a well-confirmed one.
For many years it has been know that the BBN lithium prediction was too
high by a factor of at least three as compared with measurements of
lithium in the atmosphere of old stars. The discovery of Li6 as well in
these stars has made the problem worse. On the one hand, Li6 is very
easily burned in stars, so if some of the Li7 was destroyed by stellar
nuclear reactions, all of the Li6 would have been, so the existence of the
Li6 implies that there has been very little destruction. But in addition
the Big Bang does not predict the production of any Li6. Prodanovic and
Fields assume that the Li6 is produced by cosmic rays, and find that these
must produce some Li7 as well. This makes the contradiction between the
predicted amount of Li7 and observation even worse.
The Helium abundance and Delta Y / Delta Z in Lower Main Sequence stars
Authors:
Luca Casagrande (1,2), Chris Flynn (1,2), Laura Portinari (1,2), Leo
Girardi (3), Raul Jimenez (4) ((1) Tuorla Observatory, (2) University of
Turku, (3) INAF Padova Observatory, (4) UPenn)
http://arxiv.org/abs/astro-ph/0703766v1
Monthly
Notices of the Royal Astronomical Society, Volume 382, Issue 4, Page
1516-1540, Dec 2007
Cosmological Cosmic Rays: Sharpening the Primordial Lithium Problem
Authors:
Tijana Prodanovic, Brian D. Fields
http://arxiv.org/abs/0709.3300
D.
More anisotropy
Conventional cosmology hypothesizes that the universe, on a large
scale, is isotropic. Yet this year, evidence has shown large-scale
anisotropies in measurements other than that of the CBR. Michael J. Longo
showed that spiral galaxies tend to spiral more in one direction than
another, possibly implying a large scale magnetic field in region some 350
Mpc across. The alignment of the spins seems to point in direction close
to that defined by anisotropies in the CBR.
There is also an asymmetry in the Hubble expansion, or in the velocities
of galaxies within an even large volume, some 600 Mpc or more across.
First Megan L. McClure and C. C. Dyer, and then Dominik J. Schwarz and
Bastian Weinhorst used supernova data to find that the Hubble constant is
about 10% lower in some directions than in others, implying either an
asymmetry in the process that creates the Hubble redshift, or velocities
for galaxies of up to 3,000 km/sec.
Is the Cosmic "Axis of Evil" due to a Large-Scale Magnetic
Field?
Authors:
Michael J. Longo
http://arxiv.org/abs/astro-ph/0703694v2
Does the Universe Have a Handedness?
Authors:
Michael J. Longo
http://arxiv.org/abs/astro-ph/0703325v2
Anisotropy in the Hubble constant as observed in the HST Extragalactic
Distance Scale Key Project results
Authors:
M. L. McClure, C. C. Dyer
http://arxiv.org/abs/astro-ph/0703556v1
(An)isotropy
of the Hubble diagram: comparing hemispheres
Authors:
Dominik J. Schwarz, Bastian Weinhorst
arXiv:0706.0165v1
[astro-ph]
E.
Too high surface brightness galaxies
If the universe is expanding, the surface brightness (apparent
luminosity divided by apparent surface area) of distant galaxies will be
much less than that of nearby ones. But if it is not expanding, the
surface brightness will be the same. It turns out that the surface
brightness is, in fact, the same. The conventional, Big Bang, explanation
of this observation is that the distant galaxies have extremely high
intrinsic surface brightness but with cosmological dimming, by
coincidence, they appear to have the same surface brightness as nearby
ones. One of the big problems with this explanation is that the implied
intrinsic surface brightness is much larger than that observed for any
nearby galaxies and may be physically impossible.
In 2007, Akiyama et al studying size and surface brightness of galaxies in
the optical V band find that at z=3, the highest surface brightnesses,
assuming cosmological dimming, are 16 times brighter than any in the
nearby universe. Trujillo et al looked at massive galaxies and find that
at z=1.85 the most massive, >10^11 stellar mass, galaxies are five
times smaller than nearby galaxies, taking into account the assumed
cosmological formula for converting angular dimensions to linear
dimensions. (The expanding universe formula makes objects (1+z) ^1.5 times
smaller than they would be if the universe is not expanding.) This implies
that they are 125 times denser than massive galaxies today and such dense
galaxies are not found in the nearby universe. Trujillo et al hypothesize
that mergers could reduce their density, but such mergers would make them
into extremely massive galaxies, which are very rare.
Are there really such super bright galaxies in the nearby universe? An
earlier paper by Hoopes et al had claimed to have discovered such
super-high-surface- brightness galaxies in the nearby universe. But
Riccardo Scarpa, Renato Falamo and myself point out the errors in their
analysis, indicating that no such super-galaxies have been found locally.
Overzier et al replied with Hubble Space Telescope observations that, they
claim, shows that extremely small bright galaxies do exist today, so could
have existed at high z. The catch is that only one of the galaxies
observed with HST was observed in the far UV wavelengths that the high-z
galaxies are observed at. This one galaxy had a surface brightness
intermediate between that claimed by Hoopes and that claimed for the same
galaxy by Scarpa based on ground telescope observations. There will be
much more to come on this debate in 2008.
Strong size evolution of the most massive galaxies since z~2
Authors:
Ignacio Trujillo, Christopher J. Conselice, Kevin Bundy, M. C. Cooper, P.
Eisenhardt, Richard S. Ellis
http://arxiv.org/abs/0709.0621v1
Adaptive
Optics Rest-Frame V-band Imaging of Lyman Break Galaxies at z~3:
High-surface Density Disk-like Galaxies ?
Authors:
M.Akiyama, Y.Minowa, N.Kobayashi, K.Ohta, M.Ando, I.Iwata
http://arxiv.org/abs/0709.2714v1
Title: Do local analogs of Lyman Break Galaxies exist?
Authors:
Riccardo Scarpa, Renato Falomo, Eric Lerner
http://arxiv.org/abs/0706.2948
HST morphologies of local Lyman break galaxy analogs I: Evidence for
starbursts triggered by merging
Authors:
Roderik A. Overzier, Timothy M. Heckman, Guinevere Kauffmann, Mark
Seibert, R. Michael Rich, Antara Basu-Zych, Jennifer Lotz, Alessandra
Aloisi, Stephane Charlot, Charles Hoopes, D. Christopher Martin, David
Schiminovich
http://arXiv:0709.3304v2
2.
Growth of the debate about cosmological models
In what is perhaps a sign that popular science journals are becoming more
open to talking about the problems of conventional cosmology, American
Scientist has published in its September-October issue a critique of the
Big Bang by Dr. Michael Disney . American Scientist is the publication of
Sigma Chi, the US scientific research society, and is aimed at a general
audience. The article, forthrightly titled ”Modern Cosmology, Science or
Folk-tale” demonstrates that at all points in its history the Big Bang
model has had more independent adjustable parameters than observable data
points, giving it almost no powers of prediction, the key characteristic
of scientific theories. Dr. Disney participated in the first Crisis in
Cosmology Conference.
In an as-yet unpublished paper, Richard Lieu surveys the “evidence”
for the convergence cosmology and finds it wanting, although he does not
go so far as to question the reality of the Big Bang itself.
In a survey of cosmology aimed at philosophers, Timothy Eastman concludes
that the dominant cosmology can not be taken as fully established and that
other approaches have to be considered. In his view, no current cosmology
accounts for all the observations.
Modern Cosmology, Science or Folk-tale
Author:
Micheal Disney
http://www.americanscientist.org/template/AssetDetail/assetid/55839
LambdaCDM
cosmology: how much suppression of credible evidence, and does the model
really lead its competitors, using all evidence?
Authors:
Richard Lieu
http://arxiv.org/abs/0705.2462
Cosmic Agnosticism
Author: Timothy Eastman
"Process Studies" (Vol. 36.2,
Fall-Winter 2007, pp. 181-197) (not yet online)
3.
Work on alternative theories
A. MOND work grows
Last year, there was a continued growth in the number of papers
dealing with Modified Newtonian Dynamics or MOND. MOND is an alternative
theory to dark matter as an explanation of the velocity curves of
galaxies. It hypothesizes
that gravity is stronger than in the Newtonian theory at low
accelerations.
Sky and Telescope, the leading
US amateur astronomy magazine, featured an article on MOND, the first
coverage in years in the magazine of alternative cosmology.
A number of papers described ways to develop the theory behind MOND and
make predictions with it. Other papers looked at the so-called Bullet
Cluster, a pair of colliding clusters of galaxies that was used in 2006 to
“prove” the existence of dark matter. These papers demonstrated that
MOND could describe the cluster observation better than dark matter. In
addition, Scarpa et al showed that MOND could also describe velocities of
stars in a globular cluster, which is not supposed to contain any dark
matter.
The modified Newtonian dynamics-MOND-and its implications for new physics
Authors:
Jacob D. Buckstein
http://www.arxiv.org/abs/astro-ph/0701848
Fundamental parameter-free solutions in Modified Gravity
Authors:
J. W. Moffat, V. T. Tooth
arXiv:0712.1796v2
[gr-qc]
The
collision velocity of the bullet cluster in conventional and modified
dynamics
Authors:
Garry W. Angus (St. Andrews), Stacy S. McGaugh (Maryland)
http://arxiv.org/abs/0704.0381v1
The Bullet Cluster 1E0657-558 evidence shows Modified Gravity in the
absence of Dark Matter
Authors:
J. R. Brownstein, J. W. Moffat
http://lanl.arxiv.org/abs/astro-ph/0702146
Using Globular Clusters to Test Gravity in the Weak Acceleration Regime
Authors:
Riccardo Scarpa, Gianni Marconi, Roberto Gilmozzi, Giovanni Carraro
http://www.eso.org/sci/publications/messenger/
4.
Evidence and theories about intrinsic redshifts in quasars
As in previous years, evidence continues to accumulate that quasar (QSO)
redshifts are at least in part intrinsic, and that many QSOs are no where
near as distant as the redshifts imply. Ryabinkov showed that there are
periodicities in the absorption line spectra in QSOs, a pattern that would
not be expected if the absorption lines were from intervening galaxies.
Bell and McDiarmid showed that the angular motions in quasar jets are more
easily understood if the QSOs are not at extreme distance.
There may be a plasma-based explanation of what could generate the
redshifts within the atmosphere of the quasar. Sisir Roy et al have
devoted such a theory and have compared it to quasar observations.
The redshift distribution of absorption-line systems in QSO spectra
Authors:
A.I. Ryabinkov, A.D. Kaminker, D.A. Varshalovich
http://www.arxiv.org/abs/astro-ph/0703277v1
An Abrupt Upper Envelope Cut-off in the Distribution of Angular Motions in
Quasar Jets is Compatible in all Respects with a Simple Non-Relativistic
Ejection Model
Authors:
M.B. Bell, D.R McDiarmid
arXiv:astro-ph/0701093
Dynamic Multiple Scattering, Frequency Shift and Possible Effects on
Quasar Astronomy
Authors:
Sisir Roy, Malabika Roy, Joydip Ghosh, Menas Kafatos.
http://lanl.arxiv.org/abs/astro-ph/0701071
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