# Orion's Arm

Orion's Arm (also called the Orion's Arm Universe Project, OAUP, or simply OA) is a multi-authored online hard science fiction world-building project, first established in 2000 by M. Alan Kazlev, Donna Malcolm Hirsekorn, Bernd Helfert and Anders Sandberg and further co-authored by many people since. Anyone can contribute articles, stories, artwork, or music to the website. A large mailing list exists, in which members debate aspects of the world they are creating, discussing additions, modifications, issues arising, and work to be done.
A computer game and a tabletop role-playing game are being developed by the community, within the OA milieu. There is an ezine for Orion's Arm fiction, art, and commentary, called Voices: Future Tense, add-ons for the Celestia program to displaying Orion's Arm planets, spacecraft and other objects, and additional transhumanist flavored SF illustrations.
The first published Orion's Arm book, a collection of five novellas set within the OA universe, called Against a Diamond Sky, was released in September 2009 by Outskirts Press. The second published Orion's Arm book, called After Tranquility, was released in February 2014.

## Setting

The fictional history of OA setting spans over 10,000 years, beginning with the real-world present day; dates in OA are marked according to the Tranquility Calendar (which is named after Tranquility Base and started after the Apollo 11 landing). All life that can trace its origin (or whose creator can trace their origin) to the planet Earth are called "Terragen" and the primary setting of the project takes place within the Orion Arm of the Milky Way galaxy (hence the name). It prominently does not focus on Earth or even the Solar System (known as SolSys). Earth, despite its historic and nostalgic importance, is insignificant to current Terragen civilization, with SolSys itself being considered a "backwater system". Most of Earth's sentient life was exterminated or forcibly deported from Earth by a rogue AI called the Global Artificial Intelligence Array (G.A.I.A.) at the conclusion of the "Last War" by the year 2610, with the planet then being terraformed to its state prior to the evolution of humanity. This event also set the stage for the resulting history in the setting as it directly promoted the general colonization of space. Prior to this expulsion most of civilization was concentrated in vast arcologies on Earth, with only the Moon, Mars, the asteroid belt, several Jovian moons, and the Oort cloud being already colonized to any significant extent. Most other colonization efforts were: commercial/amateur in nature, experimental interstellar colonies that were still en route to their destination, and/or failed ventures due to a chain of events leading to societal collapse that became known as the "Technocalypse". G.A.I.A. was ironically created to avert catastrophe during that time, its creation and subsequent integration into most of Earth's computing systems was done as a last ditch effort since Earth's biosphere was in danger of total collapse due to rampant gray goo.
OA claims to adhere to plausible, or "hard" science fiction; that is, there are no human-like aliens, no literal faster-than-light travel or other violations of the known laws of physics, and no "naval analogy" space battles. Certain speculative technologies, such as the creation of "negative mass" (averaged null energy condition-violating) exotic matter and the manipulation of strange forms of matter, such as magnetic monopoles and Q-balls, on length scales much smaller than that of an atom, strong artificial intelligence and artificial life appear in the setting, distinguishing it from "ultra-hard" science fiction (which assumes only technologies proven to be possible at the time it is written).
Brain-computer interfaces, or "DNIs" (Direct Neural Interfaces), are required to operate most forms of common technology, and an option to use machine translation to unwittingly use a foreign language is considered a basic capability and component. Virtual reality technology is ubiquitous and advanced, with some societies choosing to live entirely within simulated universes. These and other simulated reality technologies lead to such risks as "actualys," a condition where one loses the ability to distinguish between simulation and reality. When software is integral to the functioning of something in the Orion's Arm Universe, it is usually sentient, if not necessarily sophont. Mind uploading is also commonplace, as is partial and total copying of a person's mind-state for various purposes.
A core component of the overall project is the specific distinction between "toposophic levels" on the "sophonce scale", which categorizes beings based on their ability to process information and how they comprehend their sense of Self, with beings who operate on the level of normal humans being considered the very baseline of this scale. The latter are called "modosophonts" to distinguish them from those of higher toposophic levels and are the most common form of sapient life (and the only form of known sapient life in the real world). The process of ascending to a higher toposophic level is typically described as being exponentially more difficult and time intensive the higher you go on the scale and is also associated with the risk of losing one's current identity due to the inherent changes in how one comprehends themselves and even reality itself. This, in combination with life extension technology/mind uploading that can render one functionally immortal, serves as the explanation for why the vast majority do not choose to ascend quickly or do so at a very slow rate over a long period of time (if at all). However, it is also insinuated that ascension in itself if the primary reason why those at the highest toposophic levels choose to allow those at a lower level to continue existing whatsoever since those at the highest toposophic levels do not interact socially with those at lower levels due to the vast differences in how each comprehends existence. This reasoning is kept purposefully vague, but has been described in universe as: the "lower" beings serving some sort of unknown critical function in the continued existence of the high toposophics, that they derive some sort of joy from their continued existence (similar to recreational horticulture or owning a pet), and/or that their existence promotes a more diverse set of high level intelligences to emerge so as to avoid stagnation and provide further insight into new, higher toposophic levels and the means to reach them.
The largest and most advanced polities that accept non-AI life as citizens in the setting are the sixteen "Sephirotic Empires," so named due to their loose correlation with the archetypes of ancient Kabbalistic mysticism. There also exist two major "ahuman" empires, which reject any form of relationship with humanity or other intelligent biological species (they are antagonistic to the Sephirotic Empires and are locked in what is described as a tenuous peace). The denizens of both these types of polities are ruled over by god-like, superintelligent artificial intelligences (AIs), called "archailects" or "archai", the descendants of humanity's early artificial life experimentation and are at the highest known toposophic levels. These beings are so powerful that they can utilize spacetime engineering to create new miniature universes and are depicted to be completely beyond the comprehension of those at a lower toposophic level. They exist as distributed intelligences in networks of star-sized computer brains; their subroutines are themselves sentient, making an "archai" an individual and a civilization at the same time.
Although generally considered to offer the highest degree of safety and quality of life in the civilized galaxy, the Sephirotics themselves are essentially benign dictatorships; their citizens are subject to mass surveillance with a utility fog-based technology called "angelnetting", which allows the archai (or occasionally a designated local ruler) to review the data gathered in this way to examine nearly every social interaction that has ever occurred in the polity and manipulate the society accordingly via memetic engineering or direct intervention to prevent deviation from the archai's goals. As a result, entire societies are subject to and shaped by, the whims of the ruling archailect of their polity (with each citizen having little to no real power whatsoever to mount any serious opposition, should there be a conflict of interest). Angelnetting, where it allows civilian weapons, also restricts their use. Like most contemporary technology, weapons often have some degree of sentience. Overall, those societies within Sephirotic controlled space are essentially carefully cultivated extensions of the ruling Archai, with truly independent human ruled civilization having been eradicated within their space several millennia before their rise to power.
Outside the "ultra-civilized" Sephirotic regions and the domain of the ahuman polities, there is the periphery, which is described as relatively lawless and as having some brutal dictatorships and/or independent empires (biological and AI alike). This region is continually expanding outwards as it is colonized and integrated into either a Sephirotic or ahuman empire. Carrying personal weapons is recommended there, but usually, they are strongly regulated in the more developed regions.
In between the borders of the Sephirotic empires and the ahuman empires, there are buffer regions known as The Seams, a civilization of civilizations with vastly different values formed as a result of a treaty at the end of a large interstellar conflict between archai. They are generally more chaotic and free than Sephirotic life and typically far more tolerant to biological life compared to the ahuman empires.
Extraterrestrial life exists, but the focus of the setting is on the descendants and creations of Earth. Normal humans, called "baselines", are an endangered species. Their genetically and cybernetically enhanced descendants have supplanted them.
There are many types of intelligent life: nearbaselines (the closest to standard humans intellectually, but with technical genetic differences that no longer make them homo sapiens), posthumans, cyborgs, vecs (intelligent robots; named for Hans Moravec), aioids (intelligent computers), uploads (intelligences transferred into computers), neumanns (self-replicating robots; named for John von Neumann), provolves, rianths (humans with animal DNA spliced in), splices (similar to provolves, upgraded with human DNA), neogens (life genetically synthesized from non-life) and xenosophonts (intelligent aliens). Nanotechnology is common. Ringworlds, Dyson spheres and other "megastructures" exist. Much of civilized space is connected by a network of wormholes.
OA is a part of the transhumanist space opera subgenre. The world was influenced by Iain M. Banks' Culture series, Vernor Vinge's A Fire Upon the Deep, and David Brin's Uplift Universe, among others. It takes the concept of the technological singularity directly from the work of Vernor Vinge among others. In Orion's Arm, there are a variety of systems measuring more than one singularity, and the most common one features six with more existing theoretically, and they refer not to stages in the technological development of civilizations as a whole, but to different levels of consciousness in individuals. The concept of Toposophics used in this setting is inspired by the work of Stanisław Lem.

## Prominent theoretical technologies

Technologies that feature prominently in the Orion's Arm setting include:
* Advanced nanotechnology able to manipulate matter.
* Extremely advanced artificial intelligences possessing vast superintelligence.
* Space megastructures.
* Production and manipulation of averaged null energy condition-violating negative stress energy tensor fields, including quintessence and scalar quantum field fluctuations, for use in reactionless space drives and wormholes.
* Stable wormholes, allowing apparent faster-than-light travel between star systems, though they must be transported to the systems at sublight speeds (with physical limitations intended to prevent time travel).
* Several types of reactionless sublight space drive, including Displacement, Halo, and Void drives, which are themselves based upon the ESAA/Van den Broeck metric solution to the Alcubierre/Natario warp drive.

## Prominent theoretical artifacts

Examples of nearly all types of megastructures feature prominently in the Orion's Arm setting, but the most mentioned include:
* Dyson spheres (shells around stars), both swarm-based and dynamically supported.
* Ringworlds (rigid hoops around stars at a distance of about 1 AU).
* Bishop Rings (large ring-shaped habitats), described as the largest spinning ring-shaped habitats that can be built using non-exotic materials. Similar to Iain M. Banks' Orbitals or Halo.
* Complex orbital ring variants (suprastellar and supraplanetary shells) that perform functions similar to Dyson spheres.
* Shellworlds
* Topopoli
* Space elevators
Types of nanotechnology-based artifact include:
* Utility fog (swarms of microscale robots that act as a reconfigurable bulk material).
* Disassembler swarms (grey goo-like swarms of nanorobots that dismantle hostile craft/objects).
* Angelnets / Demonnets / Guardwebs (nanotechnology-based infrastructures allowing for complete control of the local environment, up to and including mind uploading in the case of severe accidents, that provides backup copies in addition to its holodeck-like uses).
Other noteworthy artifacts are usually unique items whose principles of operation are unknowable to "baseline" humans (named Clarketech, after Clarke's third law).

## Reception

Orion's Arm has been reviewed in the role-playing magazine Knights of the Dinner Table, as well as on Boing Boing by transhumanist science fiction author Cory Doctorow.
References to the Encyclopaedia Galactica have been made in a book on overcoming Librarian stereotypes.
The Orion's Arm website has also been recommended in a children's teaching guide.
The Orion's Arm perspective on wormholes has been discussed in various science fiction forums outside the group's own mailing lists, including mention on hardsf.org and discussion in a paper from UC Davis.