| Diaspora | |
| Author: | Greg Egan |
| Country: | Australia |
| Language: | English |
| Publisher: | Millennium |
| Release Date: | September 1997 |
| Media Type: | Print (paperback) |
| Pages: | 376 (PB edition) |
| Isbn: | 0-7528-0925-3 |
| Oclc: | 39837889 |
Diaspora is a hard science fiction novel by the Australian writer Greg Egan which first appeared in print in 1997. It originated as the short story "Wang's Carpets" which originally appeared in the Greg Bear-edited anthology New Legends (Legend, London, 1995). The story appears as a chapter of the novel.
An appended glossary explains many of the specialist terms in the novel. Egan invents several new theories of physics, beginning with Kozuch Theory, the dominant physics paradigm for nearly nine hundred years before the beginning of the novel. Kozuch Theory treats elementary particles as semi-point-like wormholes, whose properties can be explained entirely in terms of their geometries in six dimensions. Certain assumptions common to Egan's works inform the plot.
This novel's setting is a posthuman future, in which transhumanism long ago (during the mid 21st century) became the default philosophy embraced by the vast majority of human cultures.
Most of the characters choose a neutral gender; Keri Hulme's gender-neutral pronouns "ve", "vis", and "ver" are used for them.
By 2975 CE (Universal Time), the year in which the novel begins, humanity has "speciated" into three distinct groupings:
Diaspora focuses in large part on the nature of life and intelligence in a post-human context, and questions the meaning of life and the meaning of desires. If, for instance, the meaning of human life and human desires is bound up with ancestral human biology ("to spread one's genes"), then what meaning do lives and desires have, and what serves as the basis of values when biology no longer forms a part of life?
Diaspora begins with a description of "orphanogenesis", the birthing of a citizen without any ancestors (the majority of citizens descend from fleshers uploaded at some point), and the subsequent upbringing of the newborn Yatima within Konishi polis. Yatima matures within a few real-time days, because citizens' subjective time runs about 800 times as rapidly as flesher and gleisner time. Early on, Yatima and a friend, Inoshiro, use abandoned gleisner bodies to visit a Bridger colony near the ruins of Atlanta on Earth.
Years later, the gleisner Karpal, using a gravitational-wave detector, determines that a binary neutron star system in the constellation of Lacerta has collapsed, releasing a huge burst of energy. Previous predictions portrayed the system's stable orbit as likely to last for another seven million years. By analysing irregularities in the orbit, Karpal discovers that the devastating burst of energy will reach Earth within the next four days. Yatima and Inoshiro return to Earth to urge the fleshers—gathered in a conference—either to migrate to the polises or at least to shelter themselves. Many fleshers reject this advice, or fail fully to appreciate its urgency quickly enough. Stirred up by a paranoid Static diplomat, many fleshers suspect that Yatima and Inoshiro have come to trick or coerce them into "Introdus", or mass-migration into the polises, involving masses of virus-sized nanomachines that dismantle a human body and record the brain's information states as it is chemically converted into a crystalline computer. The gamma ray burst reaches Earth shortly after the conference, destroying the atmosphere and causing a mass extinction. The gleisners and the Coalition of Polises survive the burst, thanks to cosmic radiation hardening. Over the next few years, Yatima and other citizens and gleisners attempt to rescue any surviving fleshers from slow suffocation, starvation, or poisoning by offering to upload them into the polises.
The novel's title itself refers to a quest undertaken by most of the inhabitants of Carter-Zimmerman ("C-Z"), a polis devoted to physics and understanding the cosmos, along with volunteers from throughout the Coalition of Polises. The Diaspora consists of a collection of one thousand clones (physical copies of the polis hardware) of C-Z polis, deployed toward stars in all directions in the hope of gathering as much data as possible in order to revise the long-held classical understanding of Kozuch Theory, which had failed to predict the Lacerta event. The bulk of the novel follows this expedition, rotating back and forth between different cloned instances of the same cast of main characters as different C-Z clones make discoveries along the way, relaying information to one another over hundreds of light years—and finally between several universes.
Humanity began transferring itself into the polises (the Introdus) in the late 21st century UT, when the technology became feasible to effect the nanoscale transmutation of human brains into functionally indistinguishable molecular computer systems.
Many polises exist, though the novel mentions only a few. Though their physical infrastructure is not described, they apparently are hardware-based supercomputers of varying size (one of the full C-Z polis clones is briefly mentioned as roughly ten centimeters long) and unknown computational ability, all probably hidden in safe places. Konishi polis, at least, lies buried deep beneath the Siberian tundra, and is multiply backed up throughout the solar system.
Each polis has a distinct character, encapsulated in a "charter" which defines its goals, philosophies, and attitudes to other polises and to the external world. Citizens are expected to heed the charter of the polis they "live" in; should they begin to disagree with the charter, they can always migrate to a polis which appears more amenable to them.
The most prominent differences between the various polises, at least in the novel, involves their attitudes toward the physical world. Polis societies range from those who wish to experience the real world of normal time and space to the wholly solipsistic who live their entire lives in esoteric, isolated virtuality.
The citizens of Konishi polis seem to concern themselves mostly with abstract mathematics and esoteric philosophical pursuits, and generally show little interest in the physical world. They use visual icons for social purposes, but regard simulated physical interaction as a violation of individual autonomy.
After the Lacerta Event, Yatima emigrates from Konishi to Carter-Zimmerman polis, which rejects the solipsism exemplified by Konishi and embraces the study of the physical universe as of paramount importance. Given the Lacerta Event, which suggests that the universe has the capability of unleashing unknown extreme dangers, Yatima has begun to share this viewpoint.
For internal dating and time standards the polises use CST (Coalition Standard Time), measured in tau elapsed since the adoption of the system on January 1, 2065 (UT). The novel begins at CST date 23 387 025 000 000. CST defines one tau as the amount of time in which a polis citizen can experience the passage of one second of subjective time; this elastic value changes with improvements in polis hardware. In the period of the novel a polis citizen's mind can operate at a maximum speed of about 800 times that of a flesher's mind, so 1 tau equals approximately 1.25 millisecond. By the beginning of the novel, the Coalition of Polises has existed for over 741 subjective millennia (during 910 years of flesher time), of which about 98.3% has occurred since the last major Coalition-wide polis hardware upgrade in UT 2750.
Nothing compels citizens to experience time at such a high rate; they can equally choose to "rush", meaning to experience consciousness at a speed slower than the maximum the polis hardware can maintain. Citizens can therefore experience consciousness at the same speed as a human flesher would, or slower, or even freeze their conscious state for a set time or until a previously determined event occurs. Citizens in Lokhande Polis have opted to experience consciousness so slowly that they can witness continental drift and geological erosion.
The polises measure distance, an arbitrary value within their virtual scapes, in "delta", which Egan does not fully explain, although the glossary indicates that citizens' icons are generally about 2 delta high, implying that one delta represents (roughly) one meter. Delta may also be fractionalised, and there is no largest or smallest distance as defined in delta.
Almost all polis citizens, except for those who specifically elect otherwise, experience the world through two sensory modalities: Linear and Gestalt, which Egan describes as distant descendants of hearing and seeing, respectively. Linear conveys information quantitatively, as a string or strings of information formulated with a language hardwired into the mind of almost all Citizens. Citizens may "speak" to one another in Linear by sending streams of data back and forth, from mind to mind — either private conversations carried on between a specific subset of intended participants, or public announcements accessible to all involved in a conversation or otherwise "listening in".
Gestalt conveys information qualitatively, and data sent or received about anything arrives all at once for interpretation by the mind of the Citizen in all its aspects simultaneously, resulting in an experience of immediacy. A citizen need not consciously consider the information sent (as in Linear): Gestalt operates rather entirely or almost entirely subconsciously. Citizens use Gestalt to create icons for themselves — "visual" representations within Scapes (Gestalt "areas" or "spaces"). Citizens also use Gestalt to convey Tags: packages of information described as like an odour or essence, which any other Citizens within a range of several delta (or who happen to "read" for specific Tags) can gather. Each Citizen has a unique Tag which identifies them as a particular person, regardless of their other appearances, and citizens may emit Tags for other purposes as well, as when Citizens need to convey and understand arbitrary information instantly. Early in the novel, for instance, Yatima learns about an asteroid in the real world by reading its tags subconsciously, which precisely inform ver about its properties such as mass, velocity, rotation, composition, emission spectra, and other such data discernible to the Coalition's satellite network. Later on Earth, however, when ve and Inoshiro inhabit derelict Gleisner bodies, Yatima must remind that Fleshers are real people, even though they lack tags identifying themselves as such.