- Egan, Greg.
Schild's Ladder.
New York: Night Shade Books, [2002, 2004, 2013] 2015.
ISBN 978-1-59780-544-5.
-
Greg Egan is one of the most eminent contemporary
authors in the genre of
“hard”
science fiction.
By “hard”, one means not that it is necessarily
difficult to read, but that the author has taken care to
either follow the laws of known science or, if the story
involves alternative laws (for example, a faster than light
drive, anti-gravity, or time travel) to define those
laws and then remain completely consistent with them.
This needn't involve tedious lectures—masters
of science fiction, like Greg Egan,
“show, don't tell”—but the reader
should be able to figure out the rules and the
characters be constrained by them as the story
unfolds. Egan is also a skilled practitioner of
“world
building” which takes hard science fiction to
the next level by constructing entire worlds or universes
in which an alternative set of conditions are worked out
in a logical and consistent way.
Whenever a new large particle collider is proposed,
fear-mongers prattle on about the risk of its unleashing
some new physical phenomenon which might destroy the Earth or,
for those who think big, the universe by, for example, causing
it to collapse into a black hole or causing the quantum
vacuum to
tunnel
to a lower energy state where the laws of
physics are incompatible with the existence of condensed matter
and life. This is, of course, completely absurd. We have
observed cosmic rays, for example the
Oh-My-God
particle detected by an instrument in Utah in 1991,
with energies more than twenty million times greater than
those produced by the Large Hadron Collider, the most
powerful particle accelerator in existence today. These
natural cosmic rays strike the Earth, the Moon, the Sun,
and everything else in the universe all the time and have
been doing so for billions of years and, if you look
around, you'll see that the universe is still here. If a
high energy particle was going to destroy it, it would have
been gone long ago.
No, if somebody's going to destroy the universe, I'd worry
about some quiet lab in the physics building where somebody
is exploring
very
low temperatures, trying to beat the record which stands at,
depending upon how you define it, between 0.006 degrees Kelvin (for
a large block of metal) and 100 picokelvin (for nuclear spins).
These temperatures, and the physical conditions they may
create, are deeply unnatural and, unless there are similar
laboratories and apparatus created by alien scientists on
other worlds, colder than have ever existed anywhere in our universe
ever since the Big Bang.
The cosmic
microwave background radiation pervades the universe, and has
an energy at the present epoch which corresponds to a
temperature of about 2.73 degrees Kelvin. Every natural object
in the universe is bathed in this radiation so, even in the
absence of other energy sources such as starlight, anything
colder than that will heated by the background radiation until
it reaches that temperature and comes into equilibrium. (There
are a few natural processes in the universe which can temporarily
create lower temperatures, but nothing below 1° K has
ever been observed.) The temperature of the universe has been
falling ever since the Big Bang, so no lower temperature has
ever existed in the past. The only way to create a lower
temperature is to expend energy in what amounts to a super-refrigerator
that heats up something else in return for artificially cooling
its contents. In doing so, it creates a region like none other
in the known natural universe.
Whenever you explore some physical circumstance which is completely
new, you never know what you're going to find, and researchers
have been surprised many times in the past. Prior to 1911,
nobody imagined that it was possible for an electrical current
to flow with no resistance at all, and yet in early experiments
with liquid helium, the phenomenon of
superconductivity was
discovered. In 1937, it was discovered that liquid helium could
flow with zero viscosity:
superfluidity.
What might be discovered
at temperatures a tiny fraction of those where these phenomena
became manifest? Answering that question is why researchers strive
to approach ever closer to the (unattainable) absolute zero.
Might one of those phenomena destroy the universe? Could be: you'll
never know until you try.
This is the premise of this book, which is hard science fiction
but also difficult. For twenty thousand years the field of
fundamental physics has found nothing new beyond the unification of
quantum mechanics and general relativity called “Sarumpaet's
rules” or Quantum Graph Theory (QGT). The theory explained
the fabric of space and time and all of the particles and forces
within it as coarse-grained manifestations of
transformations of a graph at the Planck scale.
Researchers at Mimosa Station, 370 light years
from Earth, have built an experimental apparatus, the
Quietener, to explore conditions which have never existed
before in the universe and test Sarumpaet's Rules at the
limits. Perhaps the currently-observed laws of physics were
simply a random choice made by the universe an unimaginably
short time after the Big Bang and frozen into place by
decoherence due to interactions with the environment, analogous
to the quantum
Zeno effect. The Quietener attempts to null out every possible
external influence, even gravitational waves by carefully positioned
local cancelling sources, in the hope of reproducing the conditions
in which the early universe made its random choice and to create,
for a fleeting instant, just trillionths of a second, a region
of space with entirely different laws of physics. Sarumpaet's Rules
guaranteed that this so-called novo-vacuum would quickly
collapse, as it would have a higher energy and decay into the
vacuum we inhabit.
Oops.
Six hundred and five years after the unfortunate event at
Mimosa, the Mimosa novo-vacuum, not just stable but expanding at
half the speed of light, has swallowed more than two thousand
inhabited star systems, and is inexorably expanding through the
galaxy, transforming everything in its path to—nobody
knows. The boundary emits only an unstructured
“borderlight” which provides no clue as to what lies
within. Because the interstellar society has long ago developed
the ability to create backups of individuals, run them as
computer emulations, transmit them at light speed
from star to star, and re-instantiate them in new bodies for
fuddy-duddies demanding corporeal existence, loss of life has
been minimal, but one understands how an inexorably growing
sphere devouring everything in its path might be disturbing. The
Rindler is a research ship racing just ahead of the
advancing novo-vacuum front, providing close-up access to it for
investigators trying to figure out what it conceals.
Humans (who, with their divergently-evolved descendants,
biological and digitally emulated, are the only intelligent
species discovered so far in the galaxy) have divided, as
they remain wont to do, into two factions: Preservationists,
who view the novo-vacuum as an existential threat to the universe
and seek ways to stop its expansion and, ideally, recover
the space it has occupied; and Yielders, who believe
the novo-vacuum to be a phenomenon so unique and potentially
important that destroying it before understanding its
nature and what is on the other side of the horizon
would be unthinkable. Also, being (post-)human, the factions
are willing to resort to violence to have their way.
This leads to an adventure spanning time and space, and eventually
a mission into a region where the universe is making it up as it
goes along. This is one of the most breathtakingly
ambitious attempts at world (indeed, universe) building ever
attempted in science fiction. But for this reader, it
didn't work. First of all, when all of the principal
characters have backups stored in safe locations and can
reset, like a character in a video game with an infinite
number of lives cheat, whenever anything bad happens, it's
difficult to create dramatic tension. Humans have transcended
biological substrates, yet those still choosing them remain
fascinated with curious things about bumping their adaptive
uglies. When we finally go and explore the unknown, it's
mediated through several levels of sensors, translation,
interpretation, and abstraction, so what is described comes
across as something like a hundred pages of the acid trip
scene at the end of 2001.
In the distance, glistening partitions, reminiscent of
the algal membranes that formed the cages in some
aquatic zoos, swayed back and forth gently, as if in
time to mysterious currents. Behind each barrier the
sea changed color abruptly, the green giving way to
other bright hues, like a fastidiously segregated
display of bioluminescent plankton.
Oh, wow.
And then, it stops. I don't mean ends, as that would imply
that everything that's been thrown up in the air is somehow
resolved. There is an attempt to close the circle with the
start of the story, but a whole universe of questions are
left unanswered. The human perspective is inadequate to
describe a place where Planck length objects interact in
Planck time intervals and the laws of physics are made up
on the fly. Ultimately, the story failed for me since it
never engaged me with the characters—I didn't care
what happened to them. I'm a fan of hard science fiction,
but this was just too adamantine to be interesting.
The title, Schild's
Ladder, is taken from a method in differential geometry
which is used to approximate the parallel transport of a vector
along a curve.
July 2019 