Matchings and Canonical Forms for Symmetric Tensors
نویسندگان
چکیده
Let V be a q-dimensional vector space. Fix a set B of q(q − 1) monomials in S(V ) of the form x where ik > 0 for all k. The generic element of S(V ) is conjugate under a suitable linear transformation to an element with support off of B. We prove this by showing the existence of a perfect matching with a unique weight in a certain weighted bipartite graph. Such a perfect matching corresponds to the non-vanishing of an appropriate determinant.
منابع مشابه
2 00 3 Classification of Energy Momentum Tensors in n ≥ 5 Dimensional Space - times : a Review
Recent developments in string theory suggest that there might exist extra spatial dimensions, which are not small nor compact. The framework of a great number of brane cosmological models is that in which the matter fields are confined on a brane-world embedded in five dimensions (the bulk). Motivated by this we review the main results on the algebraic classification of second order symmetric t...
متن کاملClassification of Second Order Symmetric Tensors in 5-Dimensional Kaluza-Klein-Type Theories
An algebraic classification of second order symmetric tensors in 5-dimensional Kaluza-Klein-type Lorentzian spaces is presented by using Jordan matrices. We show that the possible Segre types are [1, 1111], [2111], [311], [z z̄ 111], and the degeneracies thereof. A set of canonical forms for each Segre type is found. The possible continuous groups of symmetry for each canonical form are also stu...
متن کاملOn the Algebraic Structure of Second Order Symmetric Tensors in 5-Dimensional Space-times
A new approach to the algebraic classification of second order symmetric tensors in 5-dimensional space-times is presented. The possible Segre types for a symmetric two-tensor are found. A set of canonical forms for each Segre type is obtained. A theorem which collects together some basic results on the algebraic structure of the Ricci tensor in 5-dimensional space-times is also stated. ∗ inter...
متن کاملA Note on Segre Types of Second Order Symmetric Tensors in 5-D Brane-world Cosmology
Recent developments in string theory suggest that there might exist extra spatial dimensions, which are not small nor compact. The framework of most brane cosmological models is that in which the matter fields are confined on a brane-world embedded in five dimensions (the bulk). Motivated by this we reexamine the classification of the second order symmetric tensors in 5–D, and prove two theorem...
متن کاملOn New Classes of Nonnegative Symmetric Tensors
In this paper we introduce three new classes of nonnegative forms (or equivalently, symmetric tensors) and their extensions. The newly identified nonnegative symmetric tensors constitute distinctive convex cones in the space of general symmetric tensors (order 6 or above). For the special case of quartic forms, they collapse into the set of convex quartic homogeneous polynomial functions. We di...
متن کامل