“…Bridgeman, Canary, Labourie and Sambarino [6] proved that Hitchin representations, are determined up to conjugacy in PGL d (R) by the spectral radii of all elements. Bridgeman and Canary [5] proved that discrete faithful representations of π 1 (S) into PSL(2, C) are determined by the translation lengths of simple non-separating curves on S. Duchin, Leininger and Rafi [12] showed that the simple marked length spectrum determines a flat surface, but that no collection of finitely many simple closed curves suffices to determine a flat surface. On the other hand, Marché and Wolff [26,Section 3] gave examples of non-conjugate, indiscrete, non-elementary representations of a closed surface group of genus two into PSL 2 (R) with the same simple marked length spectra.…”