Shoetsu Ogata (2003)
Annales de l'Institut Fourier
Similarity:
It is known that generators of ideals defining projective toric varieties of dimension embedded by global sections of normally generated line bundles have degree at most . We characterize projective toric varieties of dimension whose defining ideals must have elements of degree as generators.
Nicolae Gonciulea, Venkatramani Lakshmibai (1997)
Annales de l'institut Fourier
Similarity:
We construct certain normal toric varieties (associated to finite distributive lattices) which are degenerations of the Grassmannians. We also determine the singular loci for certain normal toric varieties, namely the ones which are certain ladder determinantal varieties. As a consequence, we prove a refined version of the conjecture of Laksmibai & Sandhya [Criterion for smoothness of Schubert varieties in , Proc. Ind. Acad. Sci., 100 (1990), 45-52] on the components of the singular...
Ewa Graczyńska, Dietmar Schweigert (2007)
Discussiones Mathematicae - General Algebra and Applications
Similarity:
Derived varieties were invented by P. Cohn in [4]. Derived varieties of a given type were invented by the authors in [10]. In the paper we deal with the derived variety of a given variety, by a fixed hypersubstitution σ. We introduce the notion of the dimension of a variety as the cardinality κ of the set of all proper derived varieties of V included in V. We examine dimensions of some varieties in the lattice of all varieties of a given type τ. Dimensions of varieties of lattices...
Alfonz Haviar, Gabriela Monoszová (2001)
Discussiones Mathematicae Graph Theory
Similarity:
In this paper we investigate varieties of orgraphs (that is, oriented graphs) as classes of orgraphs closed under isomorphic images, suborgraph identifications and induced suborgraphs, and we study the lattice of varieties of tournament-free orgraphs.
V. B. Mehta, A. Ramanathan (1988)
Compositio Mathematica
Similarity:
Mikhail V. Volkov (2010)
Discussiones Mathematicae - General Algebra and Applications
Similarity:
We prove a theorem (for arbitrary ring varieties and, in a stronger form, for varieties of associative rings) which basically reduces the problem of a description of varieties with distributive subvariety lattice to the case of algebras over a finite prime field.
J. Płonka (1987)
Colloquium Mathematicae
Similarity:
N.Ya. Medvedev, S. V. Morozova (1998)
Czechoslovak Mathematical Journal
Similarity:
Hausel, Tamás, Sturmfels, Bernd (2002)
Documenta Mathematica
Similarity: