Wikipedia / Scott information system
Wikipedia / Scott information system
In domain theory, a branch of mathematics and computer science, a Scott information system is a primitive kind of logical deductive system often used as an alternative way of presenting Scott domains.
Definition
A Scott information system, A
satisfying
Examples
Natural numbers
The return value of a partial recursive function, which either returns a natural number or goes into an infinite recursion, can be expressed as a simple Scott information system as follows:
.
.
Propositional calculus
The propositional calculus gives us a very simple Scott information system as follows:
Scott domains
Let D be a Scott domain. Then we may define an information system as follows
the set of compact elements
be the mapping that takes us from a Scott domain, D, to the information system defined above.
Information systems and Scott domains
, we can build a Scott domain as follows.
is a point if and only if
denote the set of points of A will be a countably based Scott domain when T is countable. In general, for any Scott domain D and information system A
where the second congruence is given by approximable mappings.
See also
References
Glynn Winskel: "The Formal Semantics of Programming Languages: An Introduction", MIT Press, 1993 (chapter 12)