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4 votes

An integral cohomology operation related to Steenrod square?

Such an $f$ only exists in two cases: when $k=1$ (when $\beta Sq^1 = 0$) and when $k=0$ (when $\beta Sq^0 = \beta$). Here is a proof, which will take a little work with the Steenrod algebra. Let's su …
Tyler Lawson's user avatar
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9 votes
Accepted

Associativity of Steenrod's cup-i product

The cup-i products are not associative for $i > 0$. For example, Steenrod's cup-1 product has the following description (taken mod 2 for expedience). For cocycles $f$ of degree $p$ and $g$ of degree $ …
Tyler Lawson's user avatar
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8 votes
Accepted

Massey products in the Steenrod algebra

As near as I've been able the find, the primary reference for a proof is probably Kristensen and Madsen's "On the structure of the operation algebra for certain cohomology theories." This result (in f …
Tyler Lawson's user avatar
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3 votes
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Cartan Formula for Steenrod square on cocycles

This is not necessarily true. The first warning one should give is that there are multiple definitions of "$\cup_{i}$" on cocycles, and different ones satisfy different identities. However, this is un …
Tyler Lawson's user avatar
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12 votes
Accepted

Power operations from a Tate construction

What you are looking for is probably Lecture 24 of Lurie's lecture notes on the Sullivan Conjecture. However, these kinds of results (namely, the relation between $\Sigma_2$ and operations, or the rel …
Tyler Lawson's user avatar
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14 votes

cup product and Steenrod operations in Serre spectral sequence

The behavior of the Steenrod squaring operations in the Serre spectral sequence was determined by Araki and independently by Vázquez (whose article I cannot locate online). However, it's a little work …
Tyler Lawson's user avatar
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