Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options answers only not deleted user 8103
10 votes
Accepted

Why does $\iota_4^2 \in H^8(K(\mathbb Z/2,4);\mathbb Z/2)$ not come from $H^8(K(\mathbb Z/2,...

It is true, and follows from results of Browder on the mod 2 Bockstein spectral sequence for $K(\mathbb{Z}/2,4)$. (We can replace $4$ by any even integer $k$ and conclude that $\iota_k^2$ ia not the r …
Mark Grant's user avatar
  • 35.9k
3 votes

Steenrod operations in algebraic geometry

You may be interested in the thesis of Olivier Haution, entitled Steenrod operations and quadratic forms. The author gives a new approach to constructing Steenrod operations on the Chow ring mod p, an …
Mark Grant's user avatar
  • 35.9k
5 votes

Bockstein homomorphism and Square Operations: Their consistency formulas

I'm not sure if this is what you are asking, but you get useful relations among the Bockstein operators whenever you have a map between short exact coefficient sequences. For example, using the map of …
Mark Grant's user avatar
  • 35.9k
11 votes
Accepted

Steenrod operations on cohomology of grassmannians

As in Prasit's comment, the action of the Steenrod squares on the Stiefel-Whitney classes of any vector bundle are given by Wu's formula $$ Sq^i(w_j) = \sum_{t=0}^i \binom{j+t-i-1}{t} w_{i-t} w_{j+t}. …
Mark Grant's user avatar
  • 35.9k
7 votes

Pontryagin square, Postnikov square and their consistency formulas

You may be interested in the following paper: Massey, W. S., Pontryagin squares in the Thom space of a bundle, Pac. J. Math. 31, 133-142 (1969). ZBL0188.28504. Massey proves an analogue for the Pont …
Mark Grant's user avatar
  • 35.9k