Cotangent lift of a diffeomorphism
= Cotangent lift of a diffeomorphism
{title2=$f_\#$}
For a diffeomorphism $f:X\to X$, its cotangent lift is
$$
f_\#(x,\xi)=\bigl(f(x),(df_x^{-1})^*\xi\bigr).
$$
It preserves the canonical one-form and therefore the canonical symplectic form. Cotangent lift is functorial under composition.