Alastair Reynolds - Feeling ...

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FUTURES
NATURE|Vol 437|29 September 2005
788
FUTURES
Feeling rejected
World beater.
Alastair Reynolds
Report on the paper “Analysis of the grav-
itational signals from a newly discovered
Kardashev II civilization in the Sombrero
Galaxy: Part 1 by Whimbrel
et al.
”, sub-
mitted to the
Journal of Xenoastronomical
Studies
.
The authors present an analysis of gravita-
tional signals of intelligent origin arising
in the Sombrero Galaxy, detected in
publicly available archival data from the
System-Wide Imaging Network for Exo-
astronomy (SWINE). The transmitting
culture, which has not been the subject of
an earlier paper, is shown to be a
type II civilization on the Karda-
shev scheme, by which it is under-
stood that they have the means to
tap the entire energy output of
their star. This classification is
made partly on the basis of the
strength of the SWINE signal
(which in itself implies a basic
competence in stellar husbandry)
and partly on the basis of the cul-
tural information embedded in the
datathemselves. This assessmentis
probably correct, but given the
likelihoodthatbothtypeI and type
III civilizations may occasionally
emulate type II civilizations for their own
purposes (see, for instance, Chukar, Fran-
colin and Dickcissel, 2051), a word of cau-
tionmight well havebeen in order.
The species is shown to have originated
on a rocky terrestrial planet about the size
of Mars, and to have followed an evolu-
tionary pathway that is well approximated
by the uppermost track on the three-
parameter model of Bataleur and Becard
(2049). In their unmodified form, adult
members of this species are 3-metre tall
hexapodal oxygen-breathers with a DNA-
based reproductive system. The species
has a well-developed central nervous sys-
tem withmarked hemispheric asymmetry.
The authors apply standard analysis
tools and methods to extract cultural
information from the intercepted signal.
Given the absence of anything startlingly
new in their approach, the amount of
space that the authors spend discussing
this process is puzzling. Itmight havebeen
better simply to reference one of the many
review papers on the matter, such as the
recent and comprehensive overview of
analysis methods given in [omitted].
The authors then move on to the main
part of their paper: a lengthy discussion of
the information content of the decoded
message. They summarize the nature of
the transmitting civilization, the physiol-
ogy and evolutionary background of the
inhabitants, their technology and culture.
Although broadly satisfactory in its
details, this section would benefit from
shortening. As an example, the authors
dwell on the construction methods used
in the Dyson sphere that the aliens have
erected around their star, despite the fact
that broadly similar planet-dismantling,
reforging and gravity-control methods
have been used by at least 138 other Kar-
dashev II cultures (see, for instance,
Takahe and Smew, 2045). In the very first
sentence of subsection 3.2, the authors
state that there is “nothing particularly
novel about the construction methods”,
before nevertheless embarking on a blow-
by-blow account of those selfsame meth-
ods. I agree with the first sentence.
They conclude this section by present-
ing, in excerpted form, several images and
texts deemed to be of high significance
within the culture. These include 18 ‘stan-
zas’ of a much longer epic ‘poem’ written
in commemoration of the collapse of part
of the polar region of their Dyson sphere
about 1.2 million years ago, an accident
that resulted in the deaths of
5.6 10
12
sentient beings. Although undoubtedly
touching, it is not clear that a great deal is
gained from the inclusion of this some-
what taxing material.
The authors conclude their paper by
movingontoa wider discussionofthe sig-
nificance of their newly found civilization
against the known sample of other intelli-
gent alien species. Here the authors place
(in my view) undue emphasis on the posi-
tion of their civilization in the ‘cultural
H–R diagram’ (Wonga and Grebe, 2044),
in which the total information capacity of
a transmitting culture, measured in bits, is
plotted against the light-crossing time in
light-seconds oftheir total colonized space.
On the basis of Figure 8, the authors claim
that their culture lies significantly to the
right ofthe ‘asymptotic singularity branch’,
which on the face of it would suggest that
the culture had avoided a singularity
despite occupying a total volume only
72,000 light-seconds in diameter. If true,
this would extend the total number of
known collapse-resistant cultures to eight.
The evidence, however,is verymuch less
compelling than the authors claim. Close
examination of their statistical sample
shows it to be derived from the
Third Gonolek catalogue,which is
 now known to be afflicted by seri-
ous sampling errors. Visual inspec-
tion would suggest that a more
reliable sample — such as that of
[omitted] — would either bring
their civilization into line with the
singularity branch, or reveal it as
nomorethanamildoutlier.
In short, although the new civi-
lization undoubtedly provides a
useful new datum point, I remain
unconvinced that it merits an
entire paper, and certainly not the
multi-paper saga that the authors
clearly havein mind. Thanks tothe torrent
of data supplied by SWINE, and the
planned Obscenely Large Gravity Array
(OLGA), weare fast movingintothe era of
statistical xenoastronomy — one in which
thestudy ofindividualextraterrestrial civ-
ilizations has much less to offer than a
global, survey-based approach. The
authors might therefore beadvised towait
until their archival enquiries have turned
up several dozen such cultures, and then
gather these results into a single paper.
Otherwise, I fear, they may be open to
accusations of [omitted] the [omitted].
Other matters:
Fig. 6 was incorrectly labelled (see Fig. 5).
This text has been swept by Semantic
Anonymity Preserver Version 5.1 — cer-
tain stylistic or cultural markers may have
been altered or removed. Complete legi-
bility is not guaranteed.
¦
Alastair Reynolds lives in the Netherlands.
He worked at the European Space Agency for
12 years on a variety of astronomical projects
before turning to full-time writing. His latest
book is
Century Rain
(Orion, 2004).
J
A
CEY
NaturePublishingGroup
©2005
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