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I was wondering if anyone knows any good sources for the theory of quadratic forms over fields of characteristic 2 which are written in English?

edited Mar 21 2012 at 9:45

Tom De Medts
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asked Mar 20 2012 at 12:56

Rupert
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What have you done so far? Typing the title into google gives a lot of results. So what? – Martin Brandenburg Mar 20 2012 at 13:02

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Indeed. For instance, you could look at this: jstor.org/stable/2372942 – Francesco Polizzi Mar 20 2012 at 13:04

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While indeed you could have put more work into this question, I feel obligated to mention that maybe the biggest tool in the study of quadratic forms over a field of char $\ne 2$ is the bijection with certain bilinear forms. Over a field of char $=2$ there can be many quadratic forms to a single bilinear form. Therefore, one surprising place to start if you know some alg. geom is the theory of theta characteristics, where you fix the Weil pairing on an abelian variety as your bilinear form. – stankewicz Mar 20 2012 at 13:53

I added the obvious tag "quadratic-forms". – Tom De Medts Mar 21 2012 at 9:45

Will Jagy · Answer 1 · 2012-03-21 00:40:32Z UTC

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This book by Manfred Knebusch starts with the limerick

$$\begin{array}{l}\text{A Mathematician Said Who}\cr\text{Can Quote Me a Theorem that’s True?}\cr\text{For the ones that I Know}\cr\text{Are Simply not So,}\cr\text{When the Characteristic is Two!}\end{array}$$

It gives a uniform treatment of quadratic forms in all characteristics including two.

edited Mar 21 2012 at 0:40

Will Jagy

answered Mar 21 2012 at 0:07

Peter Arndt
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Sorry for the strange formatting, I don't know how to get around that... – Peter Arndt Mar 21 2012 at 0:12

Like this. :) – Mariano Suárez-Alvarez Mar 21 2012 at 0:48

(two asterisks on each side of the word) – Mariano Suárez-Alvarez Mar 21 2012 at 0:49

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Irving Kaplansky liked to quote Marshall Hall: "The trouble with two is not that it's so small. It's that it's so even." – Will Jagy Mar 21 2012 at 0:52

Charles Matthews · Answer 2 · 2012-03-20 15:33:06Z UTC

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http://en.wikipedia.org/wiki/Arf_invariant would be a start.

answered Mar 20 2012 at 15:33

Charles Matthews
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Tom De Medts · Answer 3 · 2012-03-21 09:44:02Z UTC

The Algebraic and Geometric Theory of Quadratic Forms by Elman, Karpenko and Merkurjev is a standard recent reference for the theory of quadratic forms, paying special attention to the differences between the theory of bilinear forms and the theory of quadratic forms in characteristic 2.

quadratic forms over fields of characteristic 2

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