Definition talk:Join of Subgroups

This is simply the join (i.e., smallest upper bound) in the lattice of subgroups of $G$ under inclusion. Worth a mention and a proof. --Lord_Farin (talk) 21:30, 11 September 2012 (UTC)


 * There's a proof in place about the nature of the join being generated by the union. Feel free to add whatever other proofs you like, as I'm probably not going to explore that much further in this direction at the moment. --prime mover (talk) 05:24, 12 September 2012 (UTC)


 * I fear this will end up on the stack. But I'll make a note. --Lord_Farin (talk) 15:02, 12 September 2012 (UTC)

Rename suggestion
We could rename it to Definition:Join (Group Theory). However, due to the omnipresence of the join operation and lattices, I suggest Definition:Join of Subgroups instead. --Lord_Farin (talk) 09:08, 10 January 2013 (UTC)


 * Its usage in this context is a minor point anyway. Most texts that I've seen refer to "the group generated by $A$ and $B$" and rarely bother even mentioning this usage. It's here only through completeness of documentation of notation. --prime mover (talk) 11:43, 10 January 2013 (UTC)