Fast algorithms for computing isogenies between elliptic curves
نویسنده
چکیده
We survey algorithms for computing isogenies between elliptic curves defined over a field of characteristic either 0 or a large prime. We introduce a new algorithm that computes an isogeny of degree ` (` different from the characteristic) in time quasi-linear with respect to `. This is based in particular on fast algorithms for power series expansion of the Weierstrass ℘-function and related functions.
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