Reality Structure: Complex Vector Space, Real Part, Imaginary Number

Scalar Mathematics: Mathematics, Scalar, Linear Algebra, Real Number, Vector Space, Multiplication, Field Complex Number

Real and Imaginary Parts: Complex Number, Ordered Pair, Numbers, Unit, Black Letter

Stein Manifold: Mathematics, Several Complex Variables, Manifold, Submanifold, Vector Space, Number

State Space (Physics): Physics, Complex Number, Hilbert Space, Unit Vector, Quantum State,...