TY - JOUR ID - Adachi2022 LB - Adachi2022 AU - Adachi, Shunya TI - Monodromy invariant Hermitian forms for second order Fuchsian differential equations with four singularities ST - Monodromy invariant Hermitian forms for second order Fuchsian differential equations with four singularities JO - Opuscula Math. JA - Opuscula Math. JF - Opuscula Mathematica PY - 2022 VL - 42 IS - 3 SP - 361 EP - 391 DO - https://doi.org/10.7494/OpMath.2022.42.3.361 UR - https://doi.org/10.7494/OpMath.2022.42.3.361 AB - We study the monodromy invariant Hermitian forms for second order Fuchsian differential equations with four singularities. The moduli space of our monodromy representations can be realized by certain affine cubic surface. In this paper we characterize the irreducible monodromies having the non-degenerate invariant Hermitian forms in terms of that cubic surface. The explicit forms of invariant Hermitian forms are also given. Our result may bring a new insight into the study of the Painlevé differential equations. KW - Fuchsian differential equations KW - monodromy representation KW - monodromy invariant Hermitian form SN - 1232-9274 ER -