3 papers
math.DG2004
On the Blaschke conjecture for 3-webs
Vladislav V. Goldberg, Valentin V. Lychagin
We find relative differential invariants of orders eight and nine for a planar nonparallelizable 3-web such that their vanishing is necessary and sufficient for a 3-web to be linea…
math.DG2004
Induced connections on submanifolds in spaces with fundamental groups
Maks A. Akivis, Vladislav V. Goldberg, Arto V. Chakmazyan
The authors establish a relation of the theory of varieties with degenerate Gauss maps in projective spaces with the theory of congruences and pseudocongruences of subspaces and sh…
math.DG2004
Dually degenerate varieties and the generalization of a theorem of Griffiths--Harris
Maks A. Akivis, Vladislav V. Goldberg
The dual variety X* for a smooth n-dimensional variety X of the projective space P^N is the set of tangent hyperplanes to X. In the general case, the variety X* is a hypersurface i…