Diaspora

Penteract: A five-dimensional version of a cube. A three-dimensional cube has six square faces, twelve edges, and eight vertices. A five-dimensional penteract has ten tesseractic super-faces, forty cubic hyperfaces, eighty square faces, eighty edges, and thirty-two vertices.

Planck-Wheeler length: The length at which quantum uncertainty in the structure of space-time causes classical General Relativity to cease to apply, equal to about 10-35 meters, which is twenty orders of magnitude smaller than the size of atomic nuclei.

Polis: (1) A computer or network of computers which functions as the infrastructure for a community of conscious software. (2) The community itself.

Psychoblast: An embryonic software mind, prior to the granting of citizenship.

Psychogenesis: The creation of a new citizen by running a mind seed, or by other methods such as the assembly and customization of pre-existing components.

Riemannian space: A Riemannian space is a manifold, with two added geometrical concepts: a metric, which is a means of computing the distance between two close points, and a connection, a means of deciding whether two directions at two close points are "parallel." In the case of a surface embedded in Euclidean space, the distance between two close points in the manifold can be defined as the distance between them in the external space, and directions at two close points can he defined as "parallel" if any difference between them in the external space is perpendicular to the surface. For example, a horizontal compass needle pointing north at the equator is "parallel" in the Riemannian sense with one pointing north at a slightly higher latitude-because although they're not pointing in exactly the same direction in 3-dimensional space, the difference in direction is perpendicular to the surface of the Earth.

Rush: For a polis citizen, to rush is to experience the passage of time between external events more rapidly, by running vis own mind more slowly.

Scanning: The process of comprehensively analyzing a particular living organism and creating a software simulation of all or part of it.

Scape: A simulation of some physical or mathematical space, not necessarily 3-dimensional.

Schwarzschild radius: If an object is compressed to a size less than its Schwarzschild radius, then it will undergo gravitational collapse to form a black hole. The Schwarzschild radius is directly proportional to the mass of the object; for the sun's mass it is about three kilometers.

Semi-Riemannian space: This is a generalization of a Riemannian space, where a distinction is made between events separated by "spacelike" and "timelike" distances. Space-time in General Relativity is a four-dimensional semi-Riemannian space.

Shaper: A programming language for building elaborate structures, such as conscious neural networks, by means of iterative methods abstracted from biological processes.

Shaper: A small subprogram within a Shaper program.

Signature: The unique identifying hit string of each citizen in the Coalition of Polises. The full signature consists of public and private segments; only the signature's owner knows the private segment. Any citizen can use the public segment to encode a message that only the owner can decode.

Snapshot: A file containing a complete description of a citizen, or a scanned flesher, not actually being run as a program and hence subjectively frozen, experiencing nothing.

Sphere: See N-sphere.

Standard fiber: See fiber bundle.

Static: A flesher with no modified genes.

Symbol: The representation within a mind of a complex concept or entity—such as a person, a class of objects, or an abstract idea.

Tag: A packet of gestalt data used to convey miscellaneous non-visual information.

Tau: A unit of internal time, applicable across the Coalition of Polises. The equivalent in real time initially declined as polis hardware was improved, but stabilized around 2750 when the technology hit fundamental physical constraints. The subjective duration varies from citizen to citizen, depending on details of their minds' architecture, but some rough citizen-flesher equivalents are given below. Plural: tau.

Internal time equivalent (after 2750)

Subjective

Real time

1 tau

1 second

1 millisecond

1 kilotau

15 minutes

1 second

100 kilotau

1 day

1 min 40 sec

1 megatau

10 days

16 min 40 sec

1 gigatau

27 years

11 days 14 hours

1 teratau

27,000 years

32 years

Tesseract: A four-dimensional version of a cube. A three-dimensional cube has six square faces, twelve edges, and eight vertices. A four-dimensional tesseract has eight cubic hyperfaces, twenty-four square faces, thirty-two edges, and sixteen vertices.