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Adriano Moura

Publications and source records attributed to Adriano Moura.

29 records · Page 2Linked to original sources
arXiv2009

Restricted limits of minimal affinizations

We obtain character formulas of minimal affinizations of representations of quantum groups when the underlying simple Lie algebra is orthogonal and the support of the highest weight is contained in the first three nodes of the Dynkin diagram. We also give a framework for extending our techniques to a more general situation. In particular, for the orthogonal algebras and a highest weight supported in at most one spin node, we realize the restricted classical limit of the corresponding minimal affinizations as a quotient of a module given by generators and relations and, furthermore, show that it projects onto the submodule generated by the top weight space of the tensor product of appropriate restricted Kirillov-Reshetikhin modules. We also prove a conjecture of Chari and Pressley regarding the equivalence of certain minimal affinizations in type D4.

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arXiv2008

Finite-Dimensional Representations of Hyper Loop Algebras Over Non-Algebraically Closed Fields

We study finite-dimensional representations of hyper loop algebras over non-algebraically closed fields. The main results concern the classification of the irreducible representations, the construction of the Weyl modules, base change, tensor products of irreducible and Weyl modules, and the block decomposition of the underlying abelian category. Several results are interestingly related to the study of irreducible representations of polynomial algebras and Galois theory.

math.RT↗
arXiv2007

On Moduli Spaces for Abelian Categories

We show that if A is an abelian category satisfying certain mild conditions, then one can introduce the concept of a moduli space of (semi)stable objects which has the structure of a projective algebraic variety. This idea is applied to several important abelian categories in representation theory, like highest weight categories.

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arXiv2007

Finite-Dimensional Representations of Hyper Loop Algebras

We study finite-dimensional representations of hyper loop algebras, i.e., the hyperalgebras over an algebraically closed field of positive characteristic associated to the loop algebra over a complex finite-dimensional simple Lie algebra. The main results are the classification of the irreducible modules, a version of Steinberg's Tensor Product Theorem, and the construction of positive characteristic analogues of the Weyl modules as defined by Chari and Pressley in the characteristic zero setting. Furthermore, we start the study of reduction modulo p and prove that every irreducible module of a hyper loop algebra can be constructed as a quotient of a module obtained by a certain reduction modulo p process applied to a suitable characteristic zero module. We conjecture that the Weyl modules are also obtained by reduction modulo p. The conjecture implies a tensor product decomposition for the Weyl modules which we use to describe the blocks of the underlying abelian category.

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arXiv2006

Kirillov--Reshetikhin modules associated to G_2

We define and study the Kirillov--Reshetikhin modules for algebras of type $G_2$. We compute the graded character of these modules and verify that they are in accordance with the conjectures in math.QA/981202 and math.QA/0102113. These results give the first complete description of families of Kirillov--Reshetikhin modules whose isotypical components have multiplicity bigger than one.

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arXiv2006

The restricted Kirillov-Reshetikhin modules for the current and twisted current algebras

We define a family of graded restricted modules for the polynomial current algebra associated to a simple Lie algebra. We study the graded character of these modules and show that they are the same as the graded characters of certain Demazure modules. In particular, we see that the specialized characters are the same as those of the Kirillov Reshetikhin modules for quantum affine algebras.

math.RT↗
arXiv2005

Characters of fundamental representations of quantum affine algebras

We give closed formulae for the q-characters of the fundamental representations of the quantum loop algebra of a classical Lie algebra in terms of a family of partitions satisfying some simple properties. We also give the multiplicities of the eigenvalues of the imaginary subalgebra in terms of these partitions.

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arXiv2004

Characters and Blocks for Finite-Dimensional Representations of Quantum Affine Algebras

We introduce the notion of the ell-weight lattice and the ell-root lattice adapted to the study of finite-dimensional representations of quantum affine algebras. We then study the ell-weights of the fundamental representations and show that they are invariant under the action of the associated braid group, in the case when the underlying simple Lie algebra is of classical type. As an application of this result we are able to give explicit formulas for their q-characters. An example is worked out in detail in Section 5. Finally, we describe the blocks in the category and prove that they are parametrized by the quotient of the ell-weight lattice by the ell-root lattice.

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arXiv2004

Spectral Characters of Finite-Dimensional Representations of Affine Algebras

We introduce the notion of a spectral character for finite-dimensional representations of affine algebras. These can be viewed as a suitable q=1 limit of the elliptic characters defined by Etingof and Moura for quantum affine algebras. We show that these characters determine blocks of the category of finite-dimensional modules for affine algebras. To do this we use the Weyl modules defined by Chari and Pressley and some indecomposable reducible quotient of the Weyl modules.

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arXiv2002

On the quantum Kazhdan-Lusztig functor

We study a quantum version of the Kazhdan-Lusztig functor. Namely, we prove that there exists a fully faithfull exact tensor functor from the category of finite dimensional representations of the quantum affine algebra Uq(sl(n)) (with extended scalars) to the category of finite dimensional representations of Felder's elliptic quantum group E_{τ,\gamma2}(gl(n)).

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