English
Related papers

Related papers: Fixed point Free Actions of Spheres and Equivarian…

200 papers

This paper gives the cohomology classification of finitistic spaces X equipped with free actions of the group G = S3 and the orbit space X/G is the integral or mod 2 cohomology quaternion projective space HPn. We have proved that X is the…

Algebraic Topology · Mathematics 2021-04-13 Anju Kumari , Hemant Kumar Singh

Let X be a finitistic space with non-trivial cohomology groups H^in(X;Z)=Z with generators v_i, where i = 0, 1, 2, 3. We say that X has cohomology type (a, b) if v_1^2 = av_2 and v_1v_2 = bv_3 . In this note, we determine the mod 2…

Algebraic Topology · Mathematics 2008-08-12 Hemant Kumar Singh , Tej Bahadur Singh

Let G = S^d, d = 0, 1 or 3, act freely on a finitistic connected space X. This paper gives the cohomology classification of X if a mod 2 or rational cohomology of the orbit space X/G is isomorphic to the product of a projective space and…

Algebraic Topology · Mathematics 2023-06-07 Anju Kumari , Hemant Kumar Singh

Suppose that G=S^1 acts freely on a finitistic space X whose mod p cohomology ring isomorphic to that of a lens space L^{2m-1}(p;q_1,...,q_m). In this paper, we determine the mod p cohomology ring of the orbit space X/G. If the…

Algebraic Topology · Mathematics 2008-06-12 Hemant Kumar Singh , Tej Bahadur Singh

The orbit spaces of free S^0-actions on the mod 2 cohomology product of three spheres, S^n x S^m x S^l, 1 <= n <= m <= l have been determined in [6]. In this paper, we extend these findings to free S^1-actions on the rational cohomology…

Algebraic Topology · Mathematics 2025-06-23 Dimpi , Hemant Kumar Singh

Let $G$ be a connected Lie group of rank one. In this paper the existence of free actions of group $G$ on spheres, real projective spaces and lens spaces has been studied. Most of the results have been obtained for finitistic spaces with…

Algebraic Topology · Mathematics 2013-11-28 Hemant Kumar Singh , Jaspreet Kaur , Tej Bahadur Singh

In this paper, we investigate free actions of some compact groups on cohomology real and complex Milnor manifolds. More precisely, we compute the mod 2 cohomology algebra of the orbit space of an arbitrary free $\mathbb{Z}_2$ and…

Algebraic Topology · Mathematics 2019-09-13 Pinka Dey , Mahender Singh

Let G = Z2 act freely on a nitistic space X. If the mod 2 cohomology of X is isomorphic to the real projective space RP^{2n+1} (resp. complex projective space CP^{2n+1}) then the mod 2 cohomology of orbit spaces of these free actions are…

Algebraic Topology · Mathematics 2024-02-06 Anju Kumari , Hemant Kumar Singh

Let $X$ be a finite CW-complex having mod $p$ cohomology isomorphic to a wedge of three spheres $\mathbb{S}^n\vee \mathbb{S}^m \vee \mathbb{S}^l,~ 1\leq n \leq m \leq l$. The aim of this paper is to determine the fixed point sets of actions…

Algebraic Topology · Mathematics 2023-03-30 Dimpi , Hemant Kumar Singh

Let G be a finite group acting freely on a finitistic space X having cohomology type (0, b) (for example, S^n x S^{2n} is a space of type (0, 1) and the one-point union S^n V S^{2n} V S^{3n} is a space of type (0, 0)). It is known that a…

Algebraic Topology · Mathematics 2017-05-16 Somorjit K Singh , Hemant Kumar Singh , Tej Bahadur Singh

In this paper we prove that if $G$ is a p-torus (resp. torus) group acting without fixed points on a finitistic space X (resp. with finitely many orbit types), then the G-index $i_G(X) < 1$. Using this G-index we obtain a generalization of…

Algebraic Topology · Mathematics 2013-05-07 Satya Deo

Let $X$ be a finitistic space with the mod 2 cohomology of the product space of a projective space and a 4-sphere. Assume that $X$ admits a free involution. In this paper we study the mod 2 cohomology algebra of the quotient of $X$ by the…

Algebraic Topology · Mathematics 2023-11-14 Ying Sun , Jianbo Wang

Let $G=\mathbb{Z}_2$ act on a finite CW-complex $X$ having mod 2 cohomology isomorphic to the product of projective space and sphere $\mathbb{F}P^n\times \mathbb{S}^m,$ where $\mathbb{F}=\mathbb{R}$ or $\mathbb{C}.$ In this paper, we have…

Algebraic Topology · Mathematics 2023-03-30 Dimpi , Hemant Kumar Singh

Let $G$ be a group acting freely, properly discontinuously and cellularly on a finite dimensional $C$W-complex $\Sigma(2n)$ which has the homotopy type of the $2n$- sphere $\mathbb{S}^{2n}$. Then, this action induces an action of the group…

Algebraic Topology · Mathematics 2015-09-30 Marek Golasinski , Daciberg Lima Goncalves , Rolando Jimenez

In this paper, we have determined the orbit spaces of free involutions on a finitistic space having mod 2 cohomology of the product of three spheres $\mathbb{S}^n\times \mathbb{S}^m \times \mathbb{S}^l, 1 \leq n \leq m \leq l$. This paper…

Algebraic Topology · Mathematics 2023-03-30 Dimpi , Hemant Kumar Singh

Let $G$ be a group acting continuously on a space $X$ and let $X/G$ be its orbit space. Determining the topological or cohomological type of the orbit space $X/G$ is a classical problem in the theory of transformation groups. In this paper,…

Algebraic Topology · Mathematics 2013-10-01 Mahender Singh

Let $G = \ZZ_p$, $p$ an odd prime, act freely on a finite-dimensional CW-complex $X$ with mod $p$ cohomology isomorphic to that of a lens space $L^{2m-1} (p;q_1,...,q_m)$. In this paper, we determine the mod $p$ cohomology ring of the orbit…

Algebraic Topology · Mathematics 2007-09-24 Hemant Kumar Singh , Tej Bahadur Singh

Let G = Z2 act on a finite CW-complex X having mod 2 cohomology isomorphic to the product of quaternionic projective space and sphere HPn x Sm, n, m > or = 1. This paper is concerned with the connected fixed point sets and the orbit spaces…

Algebraic Topology · Mathematics 2023-05-05 Dimpi , Hemant Kumar Singh

Let $X$ be a finitistic space with its rational cohomology isomorphic to that of the wedge sum $P^2(n)\vee S^{3n} $ or $S^{n} \vee S^{2n}\vee S^{3n}$. We study continuous $\mathbb{S}^1$ actions on $X$ and determine the possible fixed point…

Algebraic Topology · Mathematics 2010-09-29 Mahender Singh

We use the notion of fixity for representations of finite groups to construct free and smooth actions on products of spheres. In particular we show that a finite p-group (for p>3) will act freely and smoothly on a product of two spheres if…

Algebraic Topology · Mathematics 2007-05-23 Alejandro Adem , James F. Davis , Ozgun Unlu
‹ Prev 1 2 3 10 Next ›