Tuesday, September 6, 2011 - 15:05
1 hour (actually 50 minutes)
An important question in geometry and analysis is to know when two $k$-forms $f$ and $g$ are equivalent. The problem is therefore to find a map $\varphi$ such that $\varphi^*(g) =f$. We will mostly discuss the symplectic case $k=2$ and the case of volume forms$k=n$. We will give some results on the more difficult case where $3\leq k\leq n-2$, the case $k=n-1$ will also be considered.