Character (Multiplicative)
A continuous Homeomorphism of a Group into the Nonzero Complex Numbers. Amultiplicative character 
gives a Representation on the 1-D Space 
of ComplexNumbers, where the Representation action by 
is multiplication by 
. Amultiplicative character is Unitary if it has Absolute Value 1everywhere.
References
Knapp, A. W. ``Group Representations and Harmonic Analysis, Part II.'' Not. Amer. Math. Soc. 43, 537-549, 1996.
- Archimedes Algorithm
- Archimedes' Axiom
- Archimedes' Cattle Problem
- Archimedes' Circles
- Archimedes' Constant
- Archimedes' Hat-Box Theorem
- Archimedes' Lemma
- Archimedes' Midpoint Theorem
- Archimedes' Postulate
- Archimedes' Problem
- Archimedes' Recurrence Formula
- Archimedes' Spiral
- Archimedes' Spiral Inverse
- Arc Length
- Arc Minute
- Arcsecant
- Arc Second
- Arcsine
- Arctangent
- Area
- Area Element
- Areal Coordinates
- Area-Preserving Map
- Area Principle
- Arf Invariant