Results 1 to 10 of about 9,675 (272)
On some systems of collineation groups [PDF]
, 1913 SOME systems of collineation groups which arise in connection with the theory of elliptic functions have been investigated by Klein | and HurwitzJ. One of them is a system in n variables each group of which contains an invariant subgroup of order n.
Howard H. Mitchell
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Ricci Collineations for Non-Degenerate, Diagonal and Spherically Symmetric Ricci Tensors [PDF]
Gen.Rel.Grav. 32 (2000) 285-294, 1999 The expression of the vector field generator of a Ricci Collineation for diagonal, spherically symmetric and non-degenerate Ricci tensors is obtained. The resulting expressions show that the time and radial first derivatives of the components of the Ricci tensor can be used to classify the collineation, leading to 64 families.
A. H. Bokhari +11 more
arxiv +4 more sources
Collineation group as a subgroup of the symmetric group [PDF]
Open Mathematics, 2013 Let ψ be the projectivization (i.e., the set of one-dimensional vector subspaces) of a vector space of dimension ≥ 3 over a field. Let H be a closed (in the pointwise convergence topology) subgroup of the permutation group $\mathfrak{S}_\psi $ of the set
Bogomolov Fedor, Rovinsky Marat
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symmetries of the Ricci tensor of static space times with maximal symmetric transverse spaces [PDF]
, 2006 Static space times with maximal symmetric transverse spaces are classified according to their Ricci collineations. These are investigated for non-degenerate Ricci tensor ($det.(R_{\alpha}) \neq 0$). It turns out that the only collineations admitted by these spaces can be ten, seven, six or four. Some new metrics admitting proper Ricci collineations are
A.Z. Petro +4 more
arxiv +4 more sources
Ricci Collineations in Friedmann-Robertson-Walker Spacetimes [PDF]
Class.Quant.Grav. 19 (2002) 393-404, 2001 Ricci collineations and Ricci inheritance collineations of Friedmann-Robertson-Walker spacetimes are considered. When the Ricci tensor is non-degenerate, it is shown that the spacetime always admits a fifteen parameter group of Ricci inheritance collineations; this is the maximal possible dimension for spacetime manifolds.
Uğur Camcı, Alan Barnes
arxiv +3 more sources
Matter collineations of Spacetime Homogeneous Gödel-type Metrics [PDF]
Class.Quant.Grav. 20 (2003) 2169, 2003 The spacetime homogeneous G\"odel-type spacetimes which have four classes of metrics are studied according to their matter collineations. The obtained results are compared with Killing vectors and Ricci collineations. It is found that these spacetimes have infinite number of matter collineations in degenerate case, i.e.
Uğur Camcı, M. Sharif
arxiv +3 more sources
Proper Weyl Collineations in Kantowski-Sachs and Bianchi Type III Space-Times [PDF]
, 2006 A study of proper Weyl collineations in Kantowski-Sachs and Bianchi type III space-times is given by using the rank of the 6X6 Weyl matrix and direct integration techniques. Studying proper Weyl collineations in each of the above space-times, it is shown that there exists no such possibility when the above space-times admit proper Weyl collineations.
Ghulam Shabbir, ABU BAKAR MEHMOOD
arxiv +3 more sources
Matter Collineations of Static Spacetimes with Maximal Symmetric Transverse Spaces [PDF]
ActaPhys.Polon.B38:2003-2030,2007, 2007 This paper is devoted to study the symmetries of the energy-momentum tensor for the static spacetimes with maximal symmetric transverse spaces. We solve matter collineation equations for the four main cases by taking one, two, three and four non-zero components of the vector $\xi^a$.
M. Sharif
arxiv +3 more sources
, 2001 Let G be an abelian collineation group of order n 2 of a projective plane of order n. We show that n must be a prime power, and that the p-rank of G is at least b + 1 if n = p b for an odd prime p.
Aart Blokhuis +2 more
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PROJECTIVE COLLINEATIONS AS PRODUCTS OF CYCLIC COLLINEATIONS [PDF]
Demonstratio Mathematica, 1979 Krzysztof Witczyúski
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