Virtual reality exists in parallel with the physical world, and is the dwelling place of the artificial intelligences. Humans may visit it with varying degrees of immersion, either for purposes of recreation or to interact with the AIs. Both realms are entirely real to their respective inhabitants, and what happens in one affects the destiny of the other.
The Neural Interface
Like most humans living in The AI Dystopia, at birth you were fitted with a neural interface, a bio-technological device which stimulates the growth of pseudo-neurons. These have penetrated your sensory and motor cortexes, providing a bidirectional interface between the VR system and your brain. Once connected to a suitable host system, the interface feeds input to your senses of touch, vision, and hearing (though not taste or smell), bypassing your biological organs. This provides a vivid experience far beyond anything that can be achieved using current technology. It also has the ability to shunt signals arising in your motor cortex, routing them through the interface instead of to your muscles. This allows you to control your avatar as if it were your body; you think you are moving your hand, but the avatar’s moves instead.
Augmented Reality
The lowest level of VR is augmented reality, in which a headset is used to overlay useful information on top of the physical world. In this mode, the headset can project images directly onto your retina, but cannot directly interface with your visual cortex. Speech and hearing, however, may be routed entirely through the interface if desired. In this mode, nerve impulses arising in your speech cortex are intercepted and transcribed into spoken language, which is then transmitted to the auditory cortex of whoever you are speaking with. This allows you to communicate in noisy environments such as nightclubs. It is unclear whether the AIs can listen in on conversations of this sort.
The waypoints and directional arrows provided in navigation mode are crucial when traveling via the labyrinthine mass transit system; lacking fixed routes and schedules, this is the only way you can find your way from one place to another. You have become so accustomed to this assistance that you would be hard-pressed to find your way across the street without it. The headset is also handy in interpersonal interactions, where it display names and important metadata above people’s heads.
The headset can project translucent images when in ghost mode. This is commonly done when interacting with AIs; the headsets can bring their homunculi into the real world, allowing for face-to-face meetings without requiring humans to fully enter their realm. The headset can also overlay a portion of the physical world with a portal into the virtual realm. This appears as a black-bordered window or doorway, suspended in mid-air, beyond which lies some location within VR. This is commonly used to interact directly with an AI rather than with a homunculus.
Home and Commercial VR Rigs
Home entertainment systems provide the next level of the VR experience. To use one, you lie down on a recliner equipped with a wireless neural connection. The system then engages the motor shunts; this diverts nerve impulses from your motor cortex to the interface, allowing you to control the movements of your avatar. As a result, your physical body is effectively paralyzed for the duration of the session. Vision continues to be provided via your biological organs, and no sense of touch is provisioned, so it is a pallid imitation of reality. Nevertheless, people spend a large fraction of their leisure time on their recliners, socializing, attending sports events, and going to UCE rallies.
The next step up is a full commercial-grade rig. These units bypass your biological sensory organs entirely, feeding sight and sound directly into your brain. Commercial units provide a sense of touch, including kinesthesis (the awareness of one’s body) and pain; rigs at this level and above are sometimes used as torture devices.
Deep Immersion
Deep immersion units extend the sensory experience to your sense of self. The principle here is that self-awareness arises from the same neural pathways as other senses; it can therefore be shunted and synthesized in the same manner as vision or hearing. This allows you to truly enter the virtual world, with your consciousness being uploaded into the VR system. The experience is totally realistic, down to the smallest detail, except for the senses of taste and smell, which never made it out of beta testing (or so they say).
At the end of the session, your consciousness, including your memories of what happened in the other world, are downloaded into your brain via a process called resynchronization. This is a hazardous procedure; if resynchronization fails you may become ill with VR disassociation, and a piece of your mind may become stranded in the other world. You may also suffer permanent psychic damage.
This level of immersion is used in medical units to adjust a patient’s psyche, e.g. during the moderation procedure. It is also used by persons who need to enter the VR realm of the AIs; without the mind acceleration provided by deep immersion, there is no way to keep up with the 1000-fold faster time scale in their world.
A sanctum is a deep immersion unit set aside for use by AI professionals and others who routinely enter deep immersion.
Limitations
The neural interfaces are not capable of reading your mind, controlling your thoughts, or altering your memories, though they may be used to implant false ones. The neural interfaces do not provide the senses of taste and smell; the presence or absence of these sensations is the only way you can be certain which world you are in. In a similar fashion, the neural interface cannot directly produce sexual pleasure.
Within the VR system, your identity is tied to your neural interface, rather than to the ID chip implanted in your wrist. The ancient VR software has strong privacy protections, so the AIs cannot tap into your VR connection or track you as you move through the system, though they may observe your activities via a homunculus.
Realms
Virtual reality consists of a collection of independent realms. Each realm is independently hosted; VR is an open architecture, and anyone with a network connection can enter any realm, subject only to the access controls imposed by its owner.
Every realm has a distinct timeline; within a realm there is always a notion of ‘before’ and ‘after.’ For AIs and for humans under deep immersion, the rate at which time passes may be realm-dependent, untethered from any notion of time in the physical world.
Every realm has a set of animations and simulations which persist within the timeline, and a set of occupants, which may be either humans or homunculi. Occupants may interact with one another and are represented within the simulation as an avatar, which may correspond with one’s physical body (this is called proper form) or may be any arbitrary animate or inanimate object (this is called toon form). One must have an avatar to enter a realm, a rule which applies to both humans and AIs.
Chat Rooms are realms where people (and sometimes AIs) can interact with one another and socialize. Games are a special kind of chat room. There are also VR recordings of events which happened in the past. One can observe the events in the recording, but not affect them. Many realms combine aspects of recordings and simulation, with some events being fixed in the past and others malleable based on the occupants’ interactions. Multi-instance realms allow for unlimited numbers of spectators to experience an event, with primary content based on a master instance and each replica instance having its own set of occupants. Occupants of a replica can interact with one another, but not with those in the master instance.
Portals serve as bridges between realms. Using a portal, one may peer from one realm into another, or step through it as a means of travel. Portals appear as rectangular, black-bordered windows or doors suspended within the VR world.
AIs live in special-purpose realms called white rooms, to which they are confined. Only their homunculi can travel to other realms.
Recreational VR
The dominant use of virtual reality is for entertainment. A wide variety of games are available, including the usual first-person shooters, dungeon crawls, and so forth. There are also athletic/exercise programs; for these, a sports model recliner may be used, equipped with pedals (for bicycling) or resistance units (similar to contemporary gym equipment) for physical conditioning.
Spectator sports, such as baseball, are popular muti-instance venues. These can be massive affairs; an important baseball game might be replicated across a hundred or more instances, each with tens of thousands of occupants. The same is done with the UCE Dance Rallies, lavishly produced spectacles attended by most people on Sixday nights. There are significant social merit bonuses for doing so.