Ballico, Edoardo On the real \(X\)-ranks of points of \(\mathbb P^n(\mathbb R)\) with respect to a real variety \(X \subset \mathbb P^n\). (English) Zbl 1209.14042 Ann. Univ. Mariae Curie-Skłodowska, Sect. A 64, No. 2, 15-19 (2010). Summary: Let \(X \subset \mathbb P^n\) be an integral and non-degenerate \(m\)-dimensional variety defined over \(\mathbb R\). For any \(P \in \mathbb P^n(\mathbb R)\) the real \(X\)-rank \(r_{x,\mathbb R}(P)\) is the minimal cardinality of \(S \subset X(\mathbb R)\) such that \(P \in \langle S \rangle\). Here we extend to the real case an upper bound for the \(X\)-rank due to Landsberg and Teitler. Cited in 2 Documents MSC: 14N05 Projective techniques in algebraic geometry 14H50 Plane and space curves Keywords:ranks; real variety; structured rank PDFBibTeX XMLCite \textit{E. Ballico}, Ann. Univ. Mariae Curie-Skłodowska, Sect. A 64, No. 2, 15--19 (2010; Zbl 1209.14042) Full Text: DOI