def de_rham_witt_lift(cech_class, prec = 50): C = cech_class.curve g = C.genus() omega0 = cech_class.omega0 omega8 = cech_class.omega8 fct = cech_class.f omega0_regular = regular_form(omega0) #Present omega0 in the form P dx + Q dy print('omega0_regular', omega0_regular) omega0_lift = omega0_regular[0].teichmuller()*(C.x.teichmuller().diffn()) + omega0_regular[1].teichmuller()*(C.y.teichmuller().diffn()) #Now the obvious lift of omega0 = P dx + Q dy to de Rham-Witt is [P] d[x] + [Q] d[y] print('omega8', omega8, 'second_patch(omega8)', second_patch(omega8)) omega8_regular = regular_form(second_patch(omega8)) # The same for omega8. print('omega8_regular 1', omega8_regular) omega8_regular = (second_patch(omega8_regular[0]), second_patch(omega8_regular[1])) print('omega8_regular 2', omega8_regular) u = (C.x)^(-1) v = (C.y)/(C.x)^(g+1) omega8_lift = omega8_regular[0].teichmuller()*(u.teichmuller().diffn()) + omega8_regular[1].teichmuller()*(v.teichmuller().diffn()) aux = omega0_lift - omega8_lift - fct.teichmuller().diffn() # now aux is of the form (V(smth) + dV(smth), V(smth)) return aux if aux.h1.function != 0: raise ValueError('Something went wrong - aux is not of the form (V(smth) + dV(smth), V(smth)).') decom_aux_h2 = decomposition_g0_g8(aux.h2, prec=prec) #decompose dV(smth) in aux as smth regular on U0 - smth regular on U8. aux_h2 = decom_aux_h2[0] aux_f = decom_aux_h2[2] aux_omega0 = decomposition_omega0_omega8(aux.omega, prec=prec)[0] result = superelliptic_drw_cech(omega0_lift - aux_h2.verschiebung().diffn() - aux_omega0.verschiebung(), fct.teichmuller() + aux_f.verschiebung()) return result.reduce() def crystalline_cohomology_basis(self, prec = 50): result = [] for a in self.de_rham_basis(): result += [de_rham_witt_lift(a, prec = prec)] return result superelliptic.crystalline_cohomology_basis = crystalline_cohomology_basis