Research output: Contribution to journal › Article › peer-review
On the coverings of Euclidean manifolds ℬ1 and ℬ2. / Chelnokov, G.; Deryagina, M.; Mednykh, A.
In: Communications in Algebra, Vol. 45, No. 4, 03.04.2017, p. 1558-1576.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - On the coverings of Euclidean manifolds ℬ1 and ℬ2
AU - Chelnokov, G.
AU - Deryagina, M.
AU - Mednykh, A.
PY - 2017/4/3
Y1 - 2017/4/3
N2 - There are only 10 Euclidean forms, that is flat closed three-dimensional manifolds: six are orientable and four are non-orientable. The aim of this paper is to describe all types of n-fold coverings over non-orientable Euclidean manifolds ℬ1 and ℬ2 and calculate the numbers of non-equivalent coverings of each type. We classify subgroups in the fundamental groups of ℬ1 and ℬ2 up to isomorphism and calculate the numbers of conjugated classes of each type of subgroups for index n. The manifolds ℬ1 and ℬ2 are uniquely determined among the other non-orientable forms by their homology groups Z2 X Z2 and H1B2 = Z2.
AB - There are only 10 Euclidean forms, that is flat closed three-dimensional manifolds: six are orientable and four are non-orientable. The aim of this paper is to describe all types of n-fold coverings over non-orientable Euclidean manifolds ℬ1 and ℬ2 and calculate the numbers of non-equivalent coverings of each type. We classify subgroups in the fundamental groups of ℬ1 and ℬ2 up to isomorphism and calculate the numbers of conjugated classes of each type of subgroups for index n. The manifolds ℬ1 and ℬ2 are uniquely determined among the other non-orientable forms by their homology groups Z2 X Z2 and H1B2 = Z2.
KW - Amphicosms
KW - crystallographic group
KW - Euclidean form
KW - flat 3-manifold
KW - nonequivalent coverings
KW - platycosm
KW - NUMBER
KW - SURFACE
KW - SUBGROUPS
UR - http://www.scopus.com/inward/record.url?scp=84998694344&partnerID=8YFLogxK
U2 - 10.1080/00927872.2016.1222396
DO - 10.1080/00927872.2016.1222396
M3 - Article
AN - SCOPUS:84998694344
VL - 45
SP - 1558
EP - 1576
JO - Communications in Algebra
JF - Communications in Algebra
SN - 0092-7872
IS - 4
ER -
ID: 10042803