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Book Review УDID TIME BEGIN WILL TIME END Maybe the Big Bang Never OccurredФ Paul H.

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Ann. Phys. (Berlin) 522, No. 8, 608 – 610 (2010) / DOI 10.1002/andp.201010459
Book Review
“DID TIME BEGIN? WILL TIME END? Maybe the Big Bang Never Occurred”
by Paul H. Frampton, World Scientific, Singapore (2009),
ISBN: 978-981-4280-58-7, 116 pages, USD 28.00
Friedemann Queisser∗
Institut für Theoretische Physik, Universität zu Köln, Zülpicher Straße 77, 50937 Köln, Germany
Published online: 28 June 2010
The knowledge of our universe has increased rapidly during the last decades. Therefore it is important that
not only the scientific community is enabled to learn about the modern world view. Rather the progress of
research in cosmology should be also accessible to a broad public. This is of course not a trivial task since
many conclusions that lead to the modern world view are not easily accessible.
When I read the blurb of Frampton’s “Did time begin, will time end?”, I was very curious about a book
that sought to provide twenty-first century knowledge about cosmology in a simple and comprehensible
form. Moreover, I wanted to learn about the cyclic model of the universe that is presented in the book.
Frampton begins with an explanation of cosmic distances starting from everyday length scales. Thereafter follows a brief explanation of the cornerstones in modern cosmology. Within the first chapter the
reader is confronted with Hubble’s law and cosmological red shift, the Big Bang and steady state theory,
the cosmological principle and topological issues related to the low multipoles in the cosmic microwave
background radiation (CMB), quantum gravity, cosmological singularities and inflation. Although this is
certainly a good overview on the subject, it might be too advanced for a reader who has never heard of
these issues before. Fortunately in the subsequent chapters many of those crucial points are discussed more
thoroughly.
The author turns to the large scale structure of the universe which can be related to quantum physics
during inflation. Quantum fluctuations in the early universe provide a possible explanation for the observed
structures in the universe. For this purpose the author introduces briefly the concepts of quantum mechanics
and quantum field theory. Frampton explains in detail the horizon problem and its solution by means of the
theory of inflation. Especially the role of the cosmic microwave background radiation, which supports an
inflationary period, is highlighted. One is confronted with a lot of technical terms and issues concerning
the standard model of particle physics, which are required for a deeper understanding though not necessary
for a first understanding of the subject.
In order to complete the so-called concordance model of cosmology, the author addresses the great
mysteries of cosmology: dark matter and dark energy. The dark matter problem leads naturally to the
supersymmetric extensions of the standard model and dark matter candidates like neutralinos and axions.
Frampton combines this theoretical topic with the question of how to detect these particles. At the end of
this section he focusses on the seventy-two percent of energy that are uniformly distributed in the universe
and known as dark energy.
Since the experimental verification of a theory is of great importance, Frampton dedicates one chapter
to the cornerstones of experimental cosmology that support the well-established concordance model. The
author discusses the observations of supernovae of Type 1A, the detection of acoustic peaks in the CMB
∗
E-mail: fsq@thp.uni-koeln.de
c 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Ann. Phys. (Berlin) 522, No. 8 (2010)
609
spectrum and the large scale galaxy survey leading in the end to the knowledge of the the energy distribution
in the universe.
In chapter six Frampton turns to his central concern: The future of the universe and whether time has
a beginning and an end. Since the dark energy equation of state that determines the future of the universe
is unknown so far, there is plenty of room for model building and speculations. Though a certain knowledge of the state parameter and our universe’s fate is experimentally not deducible, Frampton hopes for a
more definite theory of quantum gravity that could predict the future. Unfortunately, he takes only string
theory to be a serious candidate of quantum gravity throughout the whole book and does not mention other
approaches like canonical quantum gravity or loop quantum gravity.
In the following, I will address Framptons somewhat far-fetched speculations on cyclic cosmologies.
The author concentrates on a state parameter for the cosmological constant below minus one which is in
agreement with observations. (However, a state parameter larger than or exactly equal to minus one seems
to be equally possible).
With this choice, the scale factor of the universe becomes infinite at a finite time due to an unbounded
growth of the dark energy density. This scenario is called the Big Rip singularity [1] and can be seen as
counterpart of the Big Bang singularity. The author states that those singularities can be avoided by a model
that was conceived by himself and one of his students [2]: A cyclic model with no beginning and no end.
Framptons cyclic universe contains a finite minimal scale factor for the bounce and a finite maximal scale
factor for the turnaround that is achieved by introducing a non-standard term in the Friedmann equation.
Such a correction term can be motivated from braneworld scenarios [3]. Additionally one needs to solve an
entropy problem. Since the entropy is always increasing due to the second law of thermodynamics, entropy
will increase from cycle to cycle. Thus, extrapolation into the past will lead again to an initial singularity
which was already understood by Tolman [4]. How does Frampton solve this problem? He states that the
universe disintegrates at turnaround into more than 10103 disjoint and causal patches. A single causal patch
contains only a few number of photons and has entropy which is roughly equal to zero. Afterwards, each
causal patch contracts until the dark energy density reaches some critical value and the next cycle of cosmic
evolution starts with an inflationary period. Of course, Framptons scenario of a cyclic cosmology is highly
speculative and creates severe problems as already noted by Zhang [5]. Although the scale factor of the
universe is always a smooth function of time, the author states on page 96: “At a time somewhat later than
the unbinding of a system, the bound components become causally disconnected, meaning that they cannot
communicate even at the speed of light before the universe ends. Eventually we may regard the universe
itself as disintegrating into a huge number > 10103 of causal patches which are disjoint and separate. The
idea now is to delay the brane induced turnaround until a trillion trillionth of a second or less before the
would be Rip.” The consequence of this delay, though ignored by the author, is the reentering of all modes
that have left the horizon. Zhang noticed correctly that a similar scenario is the inflationary period in the
early universe: scales on which causal physics took place left the horizon during inflation and reentered
later. (This explains the observed thermalization of the cosmic microwave background radiation.) Since
the scale factor of the cyclic universe is always a smooth function, a shrinking to an effective scale factor
â = f a, with f < 10−28 (see [2]) and the number of causal patches (see [6]) cannot be deduced from the
model. Frampton finishes with the statement that a cyclic universe is the most likely scenario. The origin
of this conviction remains a trade secret.
Apart from the last two chapters, Frampton’s book is more or less a summary of different topics in
cosmology. Due to the significant accumulation of technical words, I would not recommend it to readers
that are completely unfamiliar with this subject. For readers having some previous knowledge of modern
cosmology, the condensed explanations might be far from satisfactory.
www.ann-phys.org
c 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
610
F. Queisser: Book Review
References
[1] R. R. Caldwell, Phys. Lett. B 545, 23 (2002); R. R. Caldwell, M. Kamionkowski, and N. N. Weinberg, Phys. Rev.
Lett. 91, 071301 (2003).
[2] L. Baum and P. H. Frampton, Phys. Rev. Lett. 98, 071301 (2007).
[3] Y. Shtanov and V. Sahni, Phys. Lett. B 557, 1 (2003).
[4] R. C. Tolman, Phys. Rev. 38, 1758 (1931).
[5] X. Zhang, Eur. Phys. J. C 59, 755 (2009).
[6] L. Baum, P. H. Frampton, and S. Matsuzaki, J. Cosmology Astropart. Phys. (JCAP) 0804, 032 (2008).
c 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.ann-phys.org
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