Algebraic Geometry and Topology: A Symposium in Honor of S. Lefschetz

a₁ Abelian varieties acyclic algebraic geometry algebraic varieties analytique B₁ base points Betti numbers birational transformation boundary bundle carrier chain cochains coefficients cohomology classes commutative compact components consider contains corresponding curves CW-complex cycles defined definition denote differential form dimension divisor element equation equivalent exists F₁ F₂ finite number fixed point follows Formel function g₁ G₂ group variety harmonic form Hence homology groups homomorphism homotopy induced integrals intersection invariant irreducible isomorphism J. H. C. Whitehead K₁ Kähler manifold Kähler metric kernel Lefschetz LEMMA Let f linear system locally connected M₁ Math metric module multiple neighborhood non-singular normal obtain operator p₁ pair proof prove rational relations result S₁ S₂ satisfies second kind sequence simplex simplicial singular space Steenrod subcomplex subgroup subset subvariety surface theorem theory topology trivial X₁ Y₁ Z₂ zero