Spear Vectors and Spear Sets

  • Vladimir Kadets
  • Miguel Martín
  • Javier Merí
  • Antonio Pérez
Part of the Lecture Notes in Mathematics book series (LNM, volume 2205)


We recall the concept of spear vector and introduce the new notion of spear set. They are both used as “leitmotiv” to give a unified presentation of the concepts of spear operator, lush operator, aDP, and other type of operators that will be introduced here. We collect some properties of spear sets and vectors, together with some (easy) examples of spear vectors.


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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  • Vladimir Kadets
    • 1
  • Miguel Martín
    • 2
  • Javier Merí
    • 2
  • Antonio Pérez
    • 3
  1. 1.School of Mathematics and Computer ScienceV. N. Karazin Kharkiv National UniversityKharkivUkraine
  2. 2.Departamento de Análisis MatemáticoUniversidad de GranadaGranadaSpain
  3. 3.Departamento de MatemáticasUniversidad de MurciaMurciaSpain

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