Normality and Quadraticity for Special Ample Line Bundles on Toric Varieties Arising from Root Systems

نویسنده

  • QËNDRIM R. GASHI
چکیده

We prove that special ample line bundles on toric varieties arising from root systems are projectively normal. Here the maximal cones of the fans correspond to the Weyl chambers, and special means that the bundle is torus-equivariant such that the character of the line bundle that corresponds to a maximal Weyl chamber is dominant with respect to that chamber. Moreover, we prove that the associated semigroup rings are quadratic.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Normal generation of very ample line bundles on toric varieties ∗

Let A and B be very ample line bundles on a projective toric variety. Then, it is proved that the multiplication map Γ(A)⊗ Γ(B) → Γ(A⊗B) of global sections of the two bundles is surjective. As a consequence, it is showed that any very ample line bundle on a projective toric variety is normally generated. As an application we show that any ample line bundle on a toric Calabi-Yau hypersurface is ...

متن کامل

Normal Projectivity of Complete Symmetric Varieties

Chiriv̀ı and Maffei [CM II] have proved that the multiplication of sections of any two ample spherical line bundles on the wonderful symmetric variety X = G/H is surjective. We have proved two criterions that allows ourselves to reduce the same problem on a (smooth) complete symmetric variety to the corresponding problem on the complete toric variety (respectively to the open toric variety). We ...

متن کامل

Syzygies, multigraded regularity and toric varieties

Using multigraded Castelnuovo-Mumford regularity, we study the equations defining a projective embedding of a variety X . Given globally generated line bundles B1, . . . , Bl on X and m1, . . . , ml ∈ N, consider the line bundle L := B m1 1 ⊗ · · · ⊗ Bl l . We give conditions on the mi which guarantee that the ideal of X in P(H (X, L)∗) is generated by quadrics and the first p syzygies are line...

متن کامل

Vanishing Results for Certain Toric Varieties Arising

Vanishing of higher cohomology groups for certain line bundles on some toric varieties arising from GLn is proved. A weaker statement is proved for G2. These two results imply a converse to Mazur’s Inequality for GLn and G2 respectively. Dedicated to Scarlett MccGwire and Christian Duhamel

متن کامل

Syzygies of Projective Toric Varieties

We study the equations defining a projective embedding of a toric variety X using multigraded Castelnuovo-Mumford regularity. Consider globally generated line bundles B1, . . . , Bl and an ample line bundle L := B ⊗m1 1 ⊗ B2 2 ⊗ · · · ⊗ Bl l on X . This article gives sufficient conditions on mi ∈ N to guarantee that the homogeneous ideal I of X in P := P (

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2013