Lower half-plane
From Wikipedia, the free encyclopedia
In mathematics, the lower half-plane H is the set of complex numbers
with positive imaginary part y. Other names are hyperbolic plane, Poincaré plane and Lobachevsky plane, particularly in texts by Russian authors. Some authors prefer the symbol 
[edit] See also
- Upper half-plane
- Cusp neighborhood
- Fuchsian group
- Fundamental domain
- Hyperbolic geometry
- Kleinian group
- Modular group
- Poincaré metric
- Riemann surface
- Schwarz-Ahlfors-Pick theorem
