Jules Henri Poincaré
The life of Jules Henri Poincaré - the Universalist Who Invented Chaos.
Poincaré Recurrence Theorem
States that certain systems will eventually return to a state very close to the initial one.
\[ T^n (A) \cap A \neq \emptyset \]
Poincaré-Hopf Index Theorem
Relating vector fields to the Euler characteristic.
\[ \sum_i \text{index}_{x_i}(v) = \chi(M) \]
Sources: https://mathshistory.st-andrews.ac.uk/Biographies/Poincare/
