THE CASE AGAINST THE BIG BANG
(A critique of "The case for the relativistic hot Big Bang cosmology")
by Tom Van Flandern
Meta Research
[The contents of this note are Copyright 1991 by the author
because an article based on them is in preparation for a journal.
Permission is granted to quote freely for purposes of discussion
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The invited review article by P.J.E. Peebles, D.N.
Schramm, E.L. Turner & R.G. Kron with the cited title was
published in the 29 August issue of NATURE, v. 352, pp. 769-776
(1991). Although the following rebuttal criticizes many points
about the Big Bang model, it should in no way be taken as a
criticism of the authors themselves, who are clearly know-
ledgeable and sincere authorities writing in their fields of
expertise.
In their introduction, the authors (henceforth abbreviated
"PSTK") cite three criteria of the Big Bang which they suggest
are essential to a good world model:
(1) It fits and even predicts the observations well.
(2) There is no known feasible alternative model.
(3) Although there are unsolved puzzles, nothing contradicts the
model.
We will argue here that:
(1) The Big Bang's predictions are of a narrow, ad hoc,
unconvincing variety.
(2) Some alternative models are feasible.
(3) There would be contradictions but for narrowing of the
definition of the standard model so as to exclude known
contradictions. We also contend that the Big Bang model
merely attempts to explain what we observe today, but does
not truly explain very much about the origin of the
universe.
Section I: The standard model
PSTK begin by defining the standard Big Bang cosmology as
one which expands according to Hubble's law. This is overly
broad, since some alternative cosmologies also have expanding
universes. By defining the Big Bang in this way, existing and
potential future contradictions to it are avoided. For example,
if the cosmic background radiation (CBR) were found to be a local
phenomenon, PSTK would apparently not count that as a strike
against the Big Bang model itself, but only against certain
variations of the basic model.
The PSTK exposition of the standard model has several
problematical concepts. Their primordial fireball provides a
reference frame for the measurement of absolute velocities, in
contradiction to a premise of the theory of relativity. Their
expanding universe has a mass density such that it met the
criteria for being a "black hole" until it had expanded to about
1000 Mpc in size. Now, depending on the values of certain
parameters, much of the universe's matter may have escaped its
event horizon, or will in the future. And the extrapolated
starting conditions imply increasing temperatures approaching
infinity at the origin. This seems opposed to the Big Bang
concept of a beginning to time itself, which implies an
unchanging (zero temperature) condition at the moment of the
origin of time.
But PSTK avoid the most important question of all for a
cosmological model, stating that "whatever started the expansion
... is not intrinsic to the standard model". There is an old
math concept that one and a google (a huge number) are both
infinitely far away from infinity. By taking reciprocals, it
follows that 10^17 seconds and 10^-40 seconds are both infinitely
far away from being infinitesimal. So in that sense, the
standard model still leaves us infinitely far from understanding
the origins of the universe. The problem is not so much that the
model doesn't deal with the question of the origin moment, as it
is that a miracle still seems required to start such a universe.
It is no coincidence that the Big Bang model has been declared
theologically acceptable in certain religions, as Hawking has
noted.
Another fundamental problem here is that the observed
cosmological redshift is not known to be due to velocity. That
interpretation is an ad hoc assumption of the standard model.
But in the standard model this assumption implies that, for the
universe to have expanded from a singularity, it would have to
overcome gravitational forces near the origin which indefinitely
exceed in strength any known forces in physics. If such
mega-forces were to exist, then how could we have confidence in
the rest of physics (e.g. the theory of black holes)?
Section II. Cosmic background radiation
PSTK cite the Big Bang's interpretation of this radiation as
a primordial fireball. This interpretation is neither unique nor
compelling. Specific problems with it are:
(1) the smoothness of the radiation is in unexpectedly sharp
contrast with the lumpiness in the distribution of galaxies.
(2) The 2.8 degree temperature of the radiation is well below
theoretical predictions of what that temperature was
expected to be in the Big Bang model (10-30 degrees).
(3) The radiation provides a frame of reference against which
absolute velocities can be measured.
(4) Lerner has shown that the brightness of radio galaxies is
sufficiently attenuated at radio wavelengths as compared
with infrared wavelengths, that no microwave radiation could
possibly get through the intergalactic medium without
absorption and re-emission many times. So the radiation we
observe cannot be coming to us directly from the
"background".
Section III. Light element abundances and neutrino counting
The abundances of heavy elements used to be an argument
against the Big Bang. Now that the standard model has accepted
that heavy elements must come from multiple generations of
stellar nucleosynthesis, it concentrates only on the light
elements. Rejecting cosmic ray spallation (the explanation for
light elements in other cosmologies), the Big Bang uses an
adjustable parameter (photon to baryon ratio) to secure good
agreement among four light elements. But the predicted helium 4
abundance is close to the value expected from multiple generation
stellar nucleosynthesis, and is therefore not significant. The
deuterium abundance is difficult to estimate, with the latest
Hubble Space Telescope values coming out smaller than Big Bang
predictions.
The implied photon to baryon ratio requires that the
curvature parameter, omega, be less than 0.1 (i.e. the universe
is open, in contradiction with certain popular versions of the
Big Bang). And a recent determination of the Beryllium abundance
indicates that element may be 1000 times more abundant than the
Big Bang predicts.
A representation that the Big Bang predicts the abundances
of the elements significantly better than any other model is
presently unjustified.
Section IV. The evolution of quasars and galaxies
PSTK suggest that distant blue galaxies represent the
predicted proto- galaxies expected by the Big Bang model. The
problem is that the Big Bang did not predict that its
proto-galaxies would look anything like the blue galaxies, whose
true nature is still quite unknown.
PSTK likewise assume that radio galaxies are an evolutionary
stage in the development of mature galaxies. But this is not
consistent with the morphologically distinct differences between
high-redshift and low-redshift radio galaxies, suggesting that
they are two different classes of object. Similarly, if quasars
and AGN's are also evolutionary stages, it would not have been
expected that their principal radiations would be non-thermal.
Incorporating all of these objects into the standard model
requires ad hoc hypotheses, and therefore cannot be taken as
"evidence" for the Big Bang.
A more serious difficulty is the time required for formation
of superclusters of galaxies -- structures so large that, at
typical galaxy relative velocities, perhaps an order of magnitude
more time than the Hubble age of the universe is required.
Section V. Quasar distances and lensing
PSTK cite Arp's argument that 20 quasars out of 4500 have a
magnitude 15 or brighter galaxy within 2 arc minutes, whereas
only 2 would be expected by chance. They then argue for
discovery bias, since quasars are looked for more often near
bright galaxies. But this argument, if true, implies that the
true quasar population to be discovered away from bright galaxies
is actually at least ten times greater, even if all known quasars
were found by only while looking near bright galaxies. I think
the observers will be surprised to hear this.
PSTK argue that high-redshift quasars near low-redshift
galaxies have absorption lines, thereby implying that the quasars
are more distant than the galaxies. But the absorption lines
show no metalicity, and therefore cannot be caused by a galaxy
halo. And the excessive number of absorption line systems in the
nearby, bright quasar 3C273 argues against the idea that
intergalactic clouds cause these absorption lines. The meaning
of the absorption lines is different in different alternative
models; but is unlikely to be as simple as the standard Big Bang
model suggests.
PSTK argue that multiple images of some quasars imply
gravitational lensing by foreground galaxies, proving that
quasars are much farther away than the galaxies, as the standard
model indicates. The difficulty is that the images are not quite
what the lensing model suggests. The optical quasar images fail
to form into Einstein rings or substantial ring arcs; are
inconsistent in the numbers of images formed; and generally fail
to be distorted or align with the hypothetical lensing galaxy,
even when a nearby galaxy can be seen at all. The observed
properties of the suggested lensing systems are not inconsistent
with multiple images formed by refraction as quasar light shines
through an intervening nebulosity. It might even be fair to
suggest that the later idea better represents what is observed
than the gravitational lens hypothesis.
PSTK state that "indications of associations between objects
with very different redshifts are well-worth following up", yet
they omit the most striking of all such examples to date,
Markarian 205, from their discussion. The unusual luminous
bridge connecting this quasar to a galaxy arm, found in
long-exposure optical images, has been confirmed in striking
detail with computer processing of the latest CCD images.
PSTK agree that, if lensing of quasar images were not
observed, it would be a serious problem for the standard model.
But the cases they call "lensing" often require chance alignments
too close to be real. For example, in Q2237+0305, the
hypothetical lensing galaxy and the background quasar must be
aligned to within about 0.1 arc seconds or so. But the total
area of the sky is 5 x 10^11 arc seconds, which is about 10^13
times greater than the area containing the "lensing" galaxy and
"background" quasar. And the quasar is not even unusually far
away, at redshift 1.7. With fewer than 10^4 quasars known, one
can readily see the statistical problems of an alignment to
within a part in 10^13 for this whole interpretation and its
requirement of chance alignments of unassociated objects.
Section VI. The timescale problem
PSTK discuss the mild inconsistency between the Hubble age
of the Big Bang universe, 10 +/- 1.3 billion years (by), versus
the radioactive decay age of the galaxy of 15 +/- 4 by, and the
globular cluster ages of 15 +/- 3 by. They point out the
unpleasant implications for simplicity of the standard model if
these ages stand up to further scrutiny. They do not discuss the
minimum time required for the formation of galactic superclusters
and voids, which appears to be far larger yet.
Section VII. Origin of galaxies
PSTK note the unexpected smoothness of the background
radiation in comparison with the highly structured distribution
of galaxies. Here they cite limits on the smoothness which, if
violated by future observations, would put the entire standard
model "in trouble". Earlier estimates of this "trouble"
threshold have already been violated.
PSTK then note that the Cold Dark Matter (CDM) version of
the standard model is apparently already in trouble, which they
describe as a "blow to simplicity" for our understanding of the
universe.
Section VIII. Alternative cosmologies
PSTK may be less familiar with alternative cosmologies than
with the standard model, because this is the only section in
which I would argue with their "facts" instead of just their
interpretation. For example, by comparing infrared and radio
wavelengths, Lerner has shown that radio galaxy luminosities do
attenuate with distance, contrary to what PSTK say. And PSTK
have applied their own equation (6), the assumption that the
background radiation (CBR) is due to a cooling fireball with a
distance-dependent temperature, to "prove" that the CBR spectrum
is inconsistent with certain other models. But most alternative
cosmologies expect a thermalized radiation source of uniform
temperature at all distances, which yields a blackbody spectrum;
so this PSTK argument is invalid.
PSTK give no consideration to alternative cosmologies in
which the cosmological redshift is due to something other than
velocity. This is certainly a serious limitation of their
discussion.
Section IX. Evaluation and opportunity
Here PSTK list possible future observations which would tend
to falsify the standard model: an important criterion for any
viable theory. These include findings of inhomogeneity in matter
distribution greater than one part in 10^4 over distances
comparable with the Hubble distance; the finding of objects with
helium 4 abundances well under 24%; or the determination of
cluster ages well in excess of the Hubble age. The difficulty,
of course, is the irresistible urge to add new hypotheses to the
model to keep it compatible with observations, no matter what may
be found in the future, as has already happened numerous times in
the history of the Big Bang model.
As scientists, we understand the necessity that models be
falsifiable; but as humans, we are loath to admit it when the
falsification criteria have been met. But perhaps we may at
least hope for a lesser goal: if any of the arguments herein, or
any future observations, should tend to undermine confidence in
the standard model, then perhaps we could return to the
scientifically more desirable status of having all viable models
on the table for future discussion and the interpretation of
observations, instead of just one of them. Our knowledge and
understanding would surely grow more rapidly from such a
scientifically commendable approach.
--
Tom Van Flandern / Washington, DC / metares@well.sf.ca.us
Meta Research was founded to foster research into ideas not otherwise
supported because they conflict with mainstream theories in Astronomy.