Arnold Conjecture & Floer Theory

Fixed points of Hamiltonian diffeomorphisms on the torus — Morse-Floer gradient flow lines connecting critical points

Hamiltonian H(x,y)

Display

H = A·cos(2πmx)cos(2πny)
+ B·cos(4πx+4πy)
∇H = (-∂H/∂y, ∂H/∂x)
Fixed pts: ∇H = 0 mod ℤ²
Fixed points found:
Arnold bound: 4mn =
Arnold conjecture (proved by Floer 1989):
#fixed pts ≥ sum of Betti numbers = 4