Shearing deformations of Hitchin representations and the Atiyah-Bott-Goldman symplectic form

The Hitchin component Hit(n)(S) of a closed surface S is a preferred component of the character variety X-PSLn (R)(S) consisting of homomorphisms from the fundamental group pi(1)(S) to the Lie group PSLn( R), whose elements enjoy remarkable geometric and dynamical properties. We consider a certain type of deformations of the elements of Hit(n)(S), called shearing deformations, and compute their pairing for the Atiyah-Bott-Goldman symplectic form of the character variety.