A note on tight projective 2?designs

A Note on Projective Graphs

7 on Tight Projective Designs

It is shown that among all tight designs in FP n = RP 1 , where F is R or C, or H (quaternions), only 5-designs in CP 1 [14] have irrational angle set. This is the only case of equal ranks of the first and the last irreducible idempotent in the corresponding Bose-Mesner algebra.

A Note on Karmarkar's Projective Transformation

This note corrects a certain inaccuracy in the discussion of the projective transformation employed by Karmarkar in the reduction of a general linear programming to the form required for his algorithm In his famous paper Karmarkar proposes on page Step a reduction of a general problem to one on a subset of the unit simplex as follows Given a linear programming problemof the form Minimize cx sub...

Tight Closure and Projective Bundles

We formulate problems of tight closure theory in terms of projective bundles and subbundles. This provides a geometric interpretation of such problems and allows us to apply intersection theory to them. This yields new results concerning the tight closure of a primary ideal in a two-dimensional graded domain.

A note on deformations of bundles on the projective line

We determine in an elementary fashion the dimension of the space of innni-tesimal deformations of an arbitrary vector bundle on the complex projective line, showing its dependence on the precise form of the decomposition of the bundle under consideration.