Talk:Formal group law

Latest comment: 9 years ago by 138.92.106.134 in topic Rational?

This is a great introduction; if someone could expand it, that would be great!

Not a group object?

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Isn't a formal group a group object in the category of formal schemes? Spakoj 12:34, 2 May 2006 (UTC)Reply

Rational?

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Over the rational numbers, there is an isomorphism from the additive formal group law to the multiplicative one, given by exp(x) − 1.

I would mention here that exp(x) is seen here as a formal power series over the rationals, exp(x)=1+x+x^2/2+x^3/6+.. and also that log(x) is seen as a formal power series over the rationals. This would make it clear why you don't need to work over the field of real numbers. — Preceding unsigned comment added by 138.92.106.134 (talk) 14:22, 8 October 2015 (UTC)Reply


O rly? —Preceding unsigned comment added by 91.45.173.61 (talk) 07:41, 14 April 2009 (UTC)Reply