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Difference between revisions of "Double coset"

From Online Dictionary of Crystallography

(Tidied translations and added German and Spanish (U. Mueller))
m (Fixed spelling mistake - "dobule" for "double")
 
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The [[complex]] ''Hg''<sub>1</sub>''K'' is  called a '''double coset'''.
 
The [[complex]] ''Hg''<sub>1</sub>''K'' is  called a '''double coset'''.
  
The partition of ''G'' into double cosets relative to ''H'' and ''K'' is a classification, ''i.e.'' each ''g<sub>i</sub>'' &isin; ''G'' belongs to exactly one dobule coset. It is also a generalization of the [[coset]] decomposition, because the double coset ''Hg''<sub>1</sub>''K'' contains complete left cosets of ''K'' and complete right cosets of ''H''.
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The partition of ''G'' into double cosets relative to ''H'' and ''K'' is a classification, ''i.e.'' each ''g<sub>i</sub>'' &isin; ''G'' belongs to exactly one double coset. It is also a generalization of the [[coset]] decomposition, because the double coset ''Hg''<sub>1</sub>''K'' contains complete left cosets of ''K'' and complete right cosets of ''H''.
  
 
=== See also ===
 
=== See also ===

Latest revision as of 15:36, 23 July 2024

Double coset (Fr). Doppelte Nebenklasse (Ge). Doppio coset (It). 両側剰余類 (Ja). Clase lateral doble (Sp).


Let G be a group, and H and K be two subgroups of G. One says that the two elements g1G and g2G belong to the same double coset of G relative to H and K if there exist elements hiH and kjK such that

g2 = hig1kj.

The complex Hg1K is called a double coset.

The partition of G into double cosets relative to H and K is a classification, i.e. each giG belongs to exactly one double coset. It is also a generalization of the coset decomposition, because the double coset Hg1K contains complete left cosets of K and complete right cosets of H.

See also