It is convenient for the poset of filters on a given set to have the reverse order to set-theoretic inclusion:
We will call it the reverse lattice of filters (since it is a lattice); compare reverse poset.
We can denote the lattice operations on as , , , , . By and we denote the minimal and maximal elements of this poset. So set-theoretically, is the filter generated by the union , is the intersection , and similarly for and , while is the improper filter (the power set) and is the filter generated by the empty set, which is .
Last revised on September 13, 2013 at 19:50:33. See the history of this page for a list of all contributions to it.