Doomsday conjecture

In algebraic topology, the doomsday conjecture was a conjecture about Ext groups over the Steenrod algebra made by Joel Cohen, named by Michael Barratt, published by and disproved by . stated a modified version called the new doomsday conjecture.
The original doomsday conjecture was that for any prime "p" and positive integer "s" there are only a finite number of permanent cycles in
 found an infinite number of permanent cycles for "p" = "s" = 2, disproving the conjecture. Minami's new doomsday conjecture is a weaker form stating (in the case "p" = 2) that there are no nontrivial permanent cycles in the image of (Sq0)"n" for "n" sufficiently large depending on "s".