ar X iv : m at h / 02 04 17 2 v 2 [ m at h . A G ] 1 8 Se p 20 02 ON THE EQUATIONS DEFINING

ar X iv : h ep - e x / 02 09 04 3 v 1 1 8 Se p 20 02 1 Elementary Hadronic Interactions at the CERN SPS

ar X iv : m at h / 02 09 26 4 v 1 [ m at h . A G ] 2 0 Se p 20 02 1 Families of p - divisible groups with constant Newton polygon

Let X be a p-divisible group with constant Newton polygon over a normal noetherian scheme S. We prove that there exists an isogeny to X → Y such that Y admits a slope filtration. In case S is regular this was proved by N.Katz for dim S = 1 and by T.Zink for dim S ≥ 1.

ar X iv : m at h / 02 08 11 9 v 5 [ m at h . A G ] 1 1 Se p 20 02 GEOMETRY OF THE TETRAHEDRON SPACE

Let X be the space of all labeled tetrahedra in P. In [1] we constructed a smooth symmetric compactification X̃ of X. In this article we show that the complement X̃ r X is a divisor with normal crossings, and we compute the cohomology ring H(X̃ ;Q).

ar X iv : m at h / 04 09 02 9 v 1 [ m at h . A G ] 2 S ep 2 00 4 ACM BUNDLES ON GENERAL HYPERSURFACES IN P 5 OF LOW DEGREE

In this paper we show that on a general hypersurface of degree r = 3, 4, 5, 6 in P 5 a rank 2 vector bundle E splits if and only if h 1 E(n) = h 2 E(n) = 0 for all n ∈ Z. Similar results for r = 1, 2 were obtained in [15], [16] and [1].

ar X iv : m at h / 04 02 39 3 v 1 [ m at h . G T ] 2 4 Fe b 20 04 CYCLIC BRANCHED COVERINGS OF ( g , 1 ) - KNOTS

We study (g, 1)-knots and their strongly-cyclic branched coverings, proving the necessary and sufficient conditions for their existence and uniqueness, and characterizing their fundamental groups. As a relevant example, we prove that generalized periodic Takahashi manifolds belong to this family of manifolds.