By a symplectic manifold (or a symplectic n-fold) we mean a compact Kaehler manifold of even dimension n with a non-degenerate holomorphic 2form ω, i.e. ω is a nowhere-vanishing n-form. This notion is generalized to a variety with singularities. We call X a projective symplectic variety if X is a normal projective variety with rational Gorenstein singularities and if the regular locus U of X ad...

Let G be a split connected reductive algebraic group. E ? B $\mathcal {E}\longrightarrow \mathcal {B}$ × $G\times G$ -torsor over smooth base scheme and X regular compactification of G. We describe the Grothendieck ring associated fibre bundle ( ) : = {E}(X):=\mathcal {E}\times _{G\times G} X$ , as an algebra canonical toric flag . These are relative versions corresponding results on in case wh...

Contents 1 Conventions and basic notation 2 2 Hilbert variety: the general framework 3 3 The Hilbert curve 8 4 Cubic Hilbert curves 12 5 Image of the Hilbert curve in P 3 17 6 Fibrations and singular points of the Hilbert curve at infinity 19 7 Serre-invariant curves 23 Abstract Let X be a normal Gorenstein complex projective variety. We introduce the Hilbert variety V X associated to the Hilbe...

An SI-sequence is a finite sequence of positive integers which is symmetric, unimodal and satisfies a certain growth condition. These are known to correspond precisely to the possible Hilbert functions of Artinian Gorenstein algebras with the Weak Lefschetz Property, a property shared by most Artinian Gorenstein algebras. Starting with an arbitrary SI-sequence, we construct a reduced, arithmeti...

Let k be a fixed field of arbitrary characteristic and let ? basic connected Nakayama k-algebra without simple projective modules. In this article we prove that if V is an indecomposable finitely generated Gorenstein-projective left ?-module, then the versal deformation ring R(?,V) (in sense F. M. Bleher author) universal stable after taking syzygies. We also following result. ?=(?B0?) triangul...

We use Quillen model structures to show a systematic method lift recollements of hereditary abelian categories their associated homotopy categories. To that end, we the notion adjoint triples and investigate transfers along pairs. Applications include liftings module derived counterpart, provide models for stable Gorenstein projective injective modules n-morphism over Iwanaga-Gorenstein rings.