Spaces of equivariant algebraic maps from real projective spaces into complex projective spaces. (English) Zbl 1311.55009

Kozlowski, Andrzej; Yamaguchi, Kohhei

RIMS Kôkyûroku Bessatsu B39, 51-61 (2013).

The inclusion map of the space of holomorphic maps \(\text{Hol}(\mathbb{C}\text{P}^m,\mathbb{C}\text{P}^n)\), between compex projective spaces of dimensions \(1\leq m\leq n\), into the corresponding space of continuous maps \(\text{Map}(\mathbb{C}\text{P}^m,\mathbb{C}\text{P}^n)\), is a homotopy equivalence up to a certain dimension. The history of such results dates back to a fundamental paper by G. Segal [Acta Math. 143, 39–72 (1979; Zbl 0427.55006)].
A similar result for the homotopy type of the space of algebraic maps \(\text{Alg}(\mathbb{R}\text{P}^m,\mathbb{R}\text{P}^n)\), between real projective spaces of dimensions \(2\leq m\leq n\), compared to the homotopy type of the space of continuous maps \(\text{Map}(\mathbb{R}\text{P}^m,\mathbb{R}\text{P}^n)\), was obtained by the authors in collaboration with M. Adamaszek [Q. J. Math. 62, No. 4, 771–790 (2011; Zbl 1245.14060)].
In this paper, the authors improve and extend similar results in their earlier paper [Contemp. Math. 519, 145–164 (2010; Zbl 1209.55005)] approximating the homotopy type of the space of real algebraic maps \(\text{Alg}(\mathbb{R}\text{P}^m,\mathbb{C}\text{P}^n)\), \(2\leq m\leq 2n\), with the homotopy type of the space of continuous maps \(\text{Map}(\mathbb{R}\text{P}^m,\mathbb{C}\text{P}^n)\).

Reviewer: Vagn Lundsgaard Hansen (Lyngby)

MSC:

55P10	Homotopy equivalences in algebraic topology
55R80	Discriminantal varieties and configuration spaces in algebraic topology
55P35	Loop spaces

Keywords:

algebraic map; homotopy equivalence