2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/160098We provide a simple algebraic construction of the twistor spaces of arbitrary Joyce's self-dual metrics on the 4-manifold H^2 x T^2 that extend smoothly to nCP^2, the connected sum of complex projective planes. Indeed, we explicitly realize projective models of the twistor spaces of arbitrary Joyce metrics on nCP^2 in a CP^4-bundle over CP^1, and show that they contain the twistor spaces of H^2 x T^2 as dense non-Zariski open subsets. In particular, we see that the last non-compact twistor spaces can be realized in rank-4 vector bundles over CP^1 by quite simple defining equations.10 pagesDifferential GeometryAlgebraic Geometry32L25; 53A30Projective models of the twistor spaces of Joyce metricstext