Browsing by Author "Rodríguez Montes, Jaime"

Now showing items 1-6 of 6

    • Algunas propiedades de regularidad de las ecuaciones diferenciales complejas 

      Rodríguez Montes, Jaime
      Two classes of differential operators, one defined by analytic functions the other by formal series, are introduced; we call them pseudo-differential operators. As auxiliary tools, and with the help of two duality theorems ...
      Universidad Nacional de Colombia Revistas electrónicas UN Revista Colombiana de Matemáticas. 

    • Aplicaciones no conmutativas y puntos fijos 

      Rodríguez Montes, Jaime
      If f, g are continuous maps of a complete metric space X such that fg = gf, d(g(x),g(y) ∝d(f (x),f (y) for some 0 and lt; ∝ and lt; 1, and g(X) ⊑ f(X) ) ⊑ X, then f, g have a common fixed point. This is a result of G. ...
      Universidad Nacional de Colombia Revistas electrónicas UN Revista Colombiana de Matemáticas. 

    • Extreme points of numerical ranges of quasihyponormal operators 

      Rodríguez Montes, Jaime
      It is shown that a quasihypnormal operator on a Hilbert space having 0 as a boundary point of its numerical range is hyponormal. A necessary and sufficient condition is given for the extreme points of the numerical range ...
      Universidad Nacional de Colombia Revistas electrónicas UN Revista Colombiana de Matemáticas. 

    • On two properties of the numerical range of a bounded hilbert space operator 

      Rodríguez Montes, Jaime
      Necessary and sufficient conditions are given for the numerical range of a bounded Hilbert space operator to have an empty interior. A sufficient condition for this set to be open is also established.
      Universidad Nacional de Colombia Revistas electrónicas UN Revista Colombiana de Matemáticas. 

    • Sobre los puntos fijos y de coincidencia de pares de aplicaciones 

      Rodríguez Montes, Jaime
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      Universidad Nacional de Colombia Revistas electrónicas UN Boletín de Matemáticas. 

    • Some results on fixed and coincidence points for pairs of maps in metric spaces 

      Rodríguez Montes, Jaime
      Following ideas of Dugundji and Granas, some general results are established on the existence of fixed and coincidence points for a pair of maps on metric spaces. Conditions on the continuity or the commutativity of the ...
      Universidad Nacional de Colombia Revistas electrónicas UN Revista Colombiana de Matemáticas.