A study is made of algebraic curves and surfaces in the flag manifold F=SU(3)/T^2, and their configuration relative to the twistor projection π from F to the complex projective plane P^2, defined with the help of an anti-holomorphic involution j. This is motivated by analogous studies of algebraic surfaces of low degree in the twistor space P^3 of the 4-dimensional sphere S^4. Deformations of twistor fibers project to real surfaces in P^2, whose metric geometry is investigated. Attention is then focussed on toric del Pezzo surfaces that are the simplest type of surfaces in F of bidegree (1,1). These surfaces define orthogonal complex structures on specified dense open subsets of P^2 relative to its Fubini-Study metric. The discriminant loci of various surfaces of bidegree (1,1) are determined, and bounds given on the number of twistor fibers that are contained in more general algebraic surfaces in F.
Twistor geometry of the Flag manifold
Amedeo Altavilla;Maria Chiara Brambilla;
2023-01-01
Abstract
A study is made of algebraic curves and surfaces in the flag manifold F=SU(3)/T^2, and their configuration relative to the twistor projection π from F to the complex projective plane P^2, defined with the help of an anti-holomorphic involution j. This is motivated by analogous studies of algebraic surfaces of low degree in the twistor space P^3 of the 4-dimensional sphere S^4. Deformations of twistor fibers project to real surfaces in P^2, whose metric geometry is investigated. Attention is then focussed on toric del Pezzo surfaces that are the simplest type of surfaces in F of bidegree (1,1). These surfaces define orthogonal complex structures on specified dense open subsets of P^2 relative to its Fubini-Study metric. The discriminant loci of various surfaces of bidegree (1,1) are determined, and bounds given on the number of twistor fibers that are contained in more general algebraic surfaces in F.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
