#### Alladi Ramakrishnan Hall

#### A topological approach to the Lorenz equations

#### Tali Pinsky

##### TIFR

*In a groundbreaking paper in 2006 Ghys proved that the set of periodic orbits of the Lorenz system coincides with the set of periodic orbits of the geodesic flow on the modular surface. We will show that the Lorenz equations can naturally be defined on the complement of the trefoil knot in $S^3$ and that essentially the Lorenz equations are a reparatmrization of the modular flow. Thus, the Lorenz equations are hyperbolic on the right domain (endowed with the right metric). This is joint work with Jennifer Creaser and Adam Clay.*

Done