{ "id": "1110.1820", "version": "v1", "published": "2011-10-09T10:50:12.000Z", "updated": "2011-10-09T10:50:12.000Z", "title": "On the geometry of four dimensional Riemannian manifold with a circulant metric and a circulant affinor structure", "authors": [ "Dimitar Razpopov" ], "comment": "4 pages", "categories": [ "math.DG" ], "abstract": "We consider a four dimensional Riemannian manifold M with a metric g and an affinor structure q. We note the local coordinates of g and q are circulant matrices. Their first orders are (A, B, C, B), A, B, C \\in FM and (0, 1, 0, 0), respectively. Let \\nabla be the connection of g. Further, let mu_{1}, mu_{2},mu_{3}, mu_{4}, mu_{5}, mu_{6} be the sectional curvatures of 2-sections {x, qx}, {x, q^{2}x}, {q^{3}x, x}, {qx, q^{2}x}, {qx, q^{3}x}, {q^{2}x, q^{3}x} for arbitrary vector x in T_{p}M$, p is in M . Then we have that q^{4}=E; g(qx, qy)=g(x,y), x, y are in chiM. The main results of the present paper are 1) There exist a q-base in T_{p}M, p is in M. 2) if \\nabla q=0, then \\mu_{1}= \\mu_{3}=\\mu_{4}=\\mu_{6}, \\mu_{2}= \\mu_{5}=0.", "revisions": [ { "version": "v1", "updated": "2011-10-09T10:50:12.000Z" } ], "analyses": { "subjects": [ "53C15", "53B20" ], "keywords": [ "dimensional riemannian manifold", "circulant affinor structure", "circulant metric", "arbitrary vector", "local coordinates" ], "note": { "typesetting": "TeX", "pages": 4, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1110.1820R" } } }