Now showing items 1-20 of 175

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      Un ejemplo de teoría de bordismo equivalente al PL-bordismo 

      Quintero Toscano, Antonio Rafael (Academia de Ciencias Exactas, Físicas, Químicas y Naturales de Zaragoza, 1983)
      In this paper we define the CPL-manifolds and we prove, by using a desingularization procedure, that these objects give a ...
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      Doble suspensión de bolas de homología 

      Quintero Toscano, Antonio Rafael (Real Academia de Ciencias Exactas, Físicas y Naturales, 1986)
      Extendemos los teoremas de doble suspensión de Edwards y Cannon a ciertas bolas de homología simplemente conexas. Como ...
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      A note on F-sectional curvatures of S-manifolds 

      Fernández Fernández, Luis Manuel (Real Academia de Ciencias de Zaragoza, 1987)
      This paper presents sorne characterizations of S-manifolds whose invariant f- sectional curvature is constant. The ...
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      Algunos resultados sobre el bordismo de variedades de homología 

      Quintero Toscano, Antonio Rafael (Real Academia de Ciencias Exactas, Físicas y Naturales, 1987)
      En este artículo probamos que las variedades de homología (HML-variedades) definen una teoría de bordismo singular que es ...
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      On totally geodesic invariant submanifolds of an S-manifold 

      Fernández Fernández, Luis Manuel (Real Academia de Ciencias de Zaragoza, 1988)
      In [1] Blair, O.E.: 1970, J. Diff. Geom. 4, (155-167), S-manifolds, which reduce in a special case to Sasakian manifolds, ...
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      Exponential law for uniformly continous proper maps 

      Ayala Gómez, Rafael; Domínguez Murillo, Eladio; Quintero Toscano, Antonio Rafael (Universitat Autònoma de Barcelona, 1988)
      The purpose of this note is to prove the exponential law for uniformly continuous proper maps.
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      Approximation axiomatique à la théorie du bordisme 

      Ayala Gómez, Rafael; Domínguez Murillo, Eladio; Quintero Toscano, Antonio Rafael (Université de Picardie Jules Verne, 1989)
      This paper gives an axiomatical approximation to Bordism Theory. It proves those properties of a geometrical nature that a class of models must satisfy to develop a bordism theory in an abstract category.
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      CR-products of S-manifolds 

      Fernández Fernández, Luis Manuel (Sociedade Portuguesa de Matemática, 1990)
      In this paper certain CR-submanifolds namely the CR-products, are studied. A characterization theorem is given and the case of CR-products of S-manifolds whose invariant f-sectional curvature is constant, is investigated.
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      A note on the homotopical characterization of Rn 

      Ayala Gómez, Rafael; Quintero Toscano, Antonio Rafael (Universitat de Barcelona, 1992)
      This note gives conditions which assure that the one-point compactification of an open manifold is a manifold. This result is used to show that the homotopical characterization of Rn (n ≥ 4) can be derived from the Poincaré Conjecture.
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      Lusternik-Schnirelmann invariants in proper homotopy theory 

      Ayala Gómez, Rafael; Domínguez Murillo, Eladio; Márquez Pérez, Alberto; Quintero Toscano, Antonio Rafael (University of California, 1992)
      We introduce and study proper homotopy invariants of the Lusternik-Schnirelmann type, p-cat (-), p-Cat(-), and cat e(-) ...
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      A classification of totally F-umbilical submanifolds of an S-manifold 

      Cabrerizo Jaraíz, José Luis; Fernández Fernández, Luis Manuel; Fernández Andrés, Manuel (Soochow University, Department of Mathematics, 1992-04)
      In this note a classification theorem for totally f-umbilical submanifolds of an S-space form is obtained.
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      Characterization of complex filiform Lie algebras of dimension 0 according to whether they are or not derived from others 

      Echarte Reula, Francisco Javier; Gómez Martín, José Ramón; Núñez Valdés, Juan (Universidad de Zaragoza, 1993)
      In this paper, we characterize those Complex Filiform Lie Algeoras of dimension 0 which are derived from other Solvable ...
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      On certain anti-invariant submanifolds of an S-manifold 

      Cabrerizo Jaraíz, José Luis; Fernández Fernández, Luis Manuel (Sociedade Portuguesa de Matemática, 1993)
      In this paper, the geometry of certain anti-invariant submanifolds of an S-manifold, namely those which are normal to the structure vector fields, is studied.
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      On the locally finite chain algebra of a proper homotopy type 

      Baues, Hans Joachim; Quintero Toscano, Antonio Rafael (Belgian Mathematical Society, 1996)
      In the classical paper [A-H] Adams-Hilton constructed a free chain algebra which is an important algebraic model of a ...
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      On pseudo-Einstein hypersurfaces of ℋ2n+s 

      Cabrerizo Jaraíz, José Luis; Fernández Fernández, Luis Manuel; Fernández Andrés, Manuel (Indian National Science Academy, 1996-05)
      In this paper, some properties of the geometry of pseudo-Einstein hypersurfaces of the S-manifold ℋ 2n+s are studied and a theorem concerning their principal curvatures is obtained.
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      On ξ-conformally flat contact metric manifolds 

      Zhen, Guo; Cabrerizo Jaraíz, José Luis; Fernández Fernández, Luis Manuel; Fernández Andrés, Manuel (Indian National Science Academy, 1997-06)
      In this paper, the notion of ξ-conformally flat on a contact metric structure is introduced and it is proved that any ...
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      A contact version of B.-Y. Chen's inequality and its applications to slant immersions 

      Carriazo Rubio, Alfonso (Kyungpook National University, 1999)
      We establish a version of B.-Y. Chen’s inequality for a submanifold of a Sasakianspace-form, tangent to the structure ...
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      Semi-slant submanifolds of a Sasakian manifold 

      Cabrerizo Jaraíz, José Luis; Carriazo Rubio, Alfonso; Fernández Fernández, Luis Manuel; Fernández Andrés, Manuel (Springer, 1999-11)
      We define and study both bi-slant and semi-slant submanifolds of an almost contact metric manifold and, in particular, of ...
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      Willmore Tori in a wide family of conformal structures on odd dimensional spheres 

      Cabrerizo Jaraíz, José Luis; Fernández Andrés, Manuel (Rocky Mountain Mathematics Consortium, 2000)
      We obtain a variable reduction principle for the Willmore variational problem in an ample class of conformal structures ...
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      Structure on a slant submanifold of a contact manifold 

      Cabrerizo Jaraíz, José Luis; Carriazo Rubio, Alfonso; Fernández Fernández, Luis Manuel; Fernández Andrés, Manuel (Indian National Science Academy, 2000-07)
      In this paper, we study the possibility of obtaining an induced contact metric structure on a slant submanifold of a contact metric manifold. We also give a characterization theorem for three-dimensional slant submanifolds.