Overview
In mathematics, a quasifield is an algebraic structure where and are binary operations on , much like a division ring, but with some weaker conditions. All division rings, and thus all fields, are quasifields.
Definition
A quasifield is a structure, where and are binary operations on , satisfying these axioms:
is a group
is a loop, where
(left distributivity)
has exactly one solution for ,
Strictly speaking, this is the definition of a left quasifield. A right quasifield is similarly defined, but satisfies right distributivity instead. A quasifield satisfying both distributive laws is called a semifield, in the sense in which the term is used in projective geometry.
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