Now showing items 183-202 of 209

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      The cyclic sliding operation in Garside groups  [Article]

      Gebhardt, Volker; González-Meneses López, Juan (Springer, 2010-05)
      We present a new operation to be performed on elements in a Garside group, called cyclic sliding, which is introduced to replace the well known cycling and decycling operations. Cyclic sliding appears to be a more natural ...
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      The defining ideals of conjugacy classes of nilpotent matrices and a conjecture of Weyman  [Article]

      Biagioli, Riccardo; Faridi, Sara; Rosas Celis, Mercedes Helena (Oxford University Press, 2008)
      Tanisaki introduced generating sets for the defining ideals of the schematic intersections of the closure of conjugacy classes of nilpotent matrices with the set of diagonal matrices. These ideals are naturally labeled by ...
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      The Gröbner fan of an An-module  [Article]

      Assi, Abdallah; Castro Jiménez, Francisco Jesús; Granger, Michel (Elsevier, 2000-06-14)
      Let I be a non-zero left ideal of the Weyl algebra An of order n over a field k and let L:R2n→R be a linear form defined by L(α,β)=∑i=1neiαi+∑i=1nfiβi. If ei+fi≥0, then L defines a filtration F•L on An. Let grL(I) be the ...
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      The Kronecker product of Schur functions indexed by two-row shapes or hook shapes  [Article]

      Rosas Celis, Mercedes Helena (Springer, 2001-09)
      The Kronecker product of two Schur functions sµ and sν, denoted by sµ ∗ sν, is the Frobenius characteristic of the tensor product of the irreducible representations of the symmetric group corresponding to the partitions ...
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      The local duality theorem in D-module theory  [Article]

      Narváez Macarro, Luis (Société Mathématique de France, 2004)
      These notes are devoted to the Local Duality Theorem for D-modules, which asserts that the topological Grothendieck-Verdier duality exchanges the de Rham complex and the solution complex of holonomic modules over a complex ...
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      The module Dfs for locally quasi-homogeneous free divisors  [Article]

      Calderón Moreno, Francisco Javier; Narváez Macarro, Luis (Springer, 2002-10)
      We find explicit free resolutions for the D-modules Dfs and D[s]fs/D[s]f s+1, where f is a reduced equation of a locally quasi-homogeneous free divisor. These results are based on the fact that every locally quasi-homogeneous ...
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      The Newton Procedure for several variables  [Article]

      Soto Prieto, Manuel Jesús; Vicente Córdoba, José Luis (Elsevier, 2011-07-15)
      Let us consider an equation of the form P(x, z) = zm + w1(x)zm−1 + · · · + wm−1(x)z + wm(x) = 0, where m>1, n>1, x=(x1⋯xn) is a vector of variables, k is an algebraically closed field of characteristic zero, View the ...
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      The nth root of a braid is unique up to conjugacy  [Article]

      González-Meneses López, Juan (Mathematical Sciences Publishers, 2003-11-01)
      We prove a conjecture due to Makanin: if α and β are elements of the Artin braid group Bn such that α k = β k for some nonzero integer k, then α and β are conjugate. The proof involves the Nielsen-Thurston classification ...
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      The regularity of a toric variety  [Article]

      Briales Morales, Emilio; Pisón Casares, Pilar (Elsevier, 2001-03-01)
      We give a method for computing the degrees of the minimal syzygies of a toric variety by means of combinatorial techniques. Indeed, we complete the explicit description of the minimal free resolution of the associated ...
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      The stability of the Kronecker products of Schur functions  [Article]

      Briand, Emmanuel; Orellana, Rosa C.; Rosas Celis, Mercedes Helena (Elsevier, 2011-04-01)
      In the late 1930’s Murnaghan discovered the existence of a stabilization phenomenon for the Kronecker product of Schur functions. For n sufficiently large, the values of the Kronecker coefficients appearing in the product ...
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      The symmetric action on secondary homotopy groups  [Article]

      Baues, Hans Joachim; Muro Jiménez, Fernando (The Belgian Mathematical Society, 2008-11)
      We show that the symmetric track groups Sym(n), which are extensions of the symmetric groups Sym(n) associated to the second Stiefel-Whitney class, act as crossed modules on the secondary homotopy groups of a pointed space.
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      Thue equations and torsion groups of elliptic curves  [Article]

      García Selfa, Irene; Tornero Sánchez, José María (Elsevier, 2009-02)
      A new characterization of rational torsion subgroups of elliptic curves is found, for points of order greater than 4, through the existence of solution for systems of Thue equations.
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      Toda brackets and cup-one squares for ring spectra  [Article]

      Baues, Hans Joachim; Muro Jiménez, Fernando (Taylor & Francis, 2009)
      In this paper we prove the laws of Toda brackets on the homotopy groups of a connective ring spectrum and the laws of the cup-one square in the homotopy groups of a commutative connective ring spectrum.
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      Torsion homology and cellular approximation  [Article]

      Flores Díaz, Ramón Jesús; Muro Jiménez, Fernando (Mathematical Sciences Publishers, 2019-02-06)
      We describe the role of the Schur multiplier in the structure of the p-torsion of discrete groups. More concretely, we show how the knowledge of H2G allows us to approximate many groups by colimits of copies of p-groups. ...
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      Torsion of rational elliptic curves over cubic fields  [Article]

      González Jiménez, Enrique; Najman, Filip; Tornero Sánchez, José María (Rocky Mountain Mathematics Consortium, 2016)
      Let E be an elliptic curve defined over Q. We study the relationship between the torsion subgroup E(Q)tors and the torsion subgroup E(K)tors, where K is a cubic number field. In particular, we study the number of cubic ...
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      Torsion of rational elliptic curves over quadratic fields  [Article]

      González Jiménez, Enrique; Tornero Sánchez, José María (Springer, 2014-09)
      Let E be an elliptic curve defined over Q. We study the relationship between the torsion subgroup E(Q)tors and the torsion subgroup E(K)tors, where K is a quadratic number field.
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      Torsion of rational elliptic curves over quadratic fields II  [Article]

      González Jiménez, Enrique; Tornero Sánchez, José María (Springer, 2016-03)
      Let E be an elliptic curve defined over Q and let G=E(Q)_tors be the associated torsion group. In a previous paper, the authors studied, for a given G, which possible groups G\leq H could appear such that H=E(K)_tors, for ...
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      Transfinite Adams representability  [Article]

      Muro Jiménez, Fernando; Raventós Morera, Oriol (Elsevier, 2016-04-09)
      We consider the following problems in a well generated triangulated category T . Let α be a regular cardinal and T α ⊂ T the full subcategory of α-compact objects. Is every functor H : (T α) op → Ab that preserves products ...
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      Triangulated categories without models  [Article]

      Muro Jiménez, Fernando; Schwede, Stefan; Strickland, Neil (Springer, 2007-11)
      We exhibit examples of triangulated categories which are neither the stable category of a Frobenius category nor a full triangulated subcategory of the homotopy category of a stable model category. Even more drastically ...
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      Twisted conjugacy in braid groups  [Article]

      González-Meneses López, Juan; Ventura Capell, Enric (Springer, 2014)
      In this note we solve the twisted conjugacy problem for braid groups, i.e. we propose an algorithm which, given two braids u, v ∈ Bn and an automorphism ϕ ∈ Aut(Bn), decides whether v = (ϕ(x))−1ux for some x ∈ Bn. As a ...