# News & Events

## NISER Colloquium

Date/Time:
Friday, October 26, 2018 - 16:00 to 17:00
Venue:
LH-5
Speaker:
Parameswaran Shankaran
Affiliation:
IMSc Chennai
Title:
The geometry of the upper half-space

The parallel postulate of the Euclidean geometry says that there is exactly one straight line that is parallel to a given line l and passes through a given point P which is not on l. There are several equivalent axioms---such as the sum of the angles in a triangle equals $\pi$. We will see that there are geometries where the parallel postulate fails. One such is the geometry of the Poincaré upper half-space. We will point out some interesting features of the upper half-space.