Let
be an elliptic curve over a number
field
,
and let
be the absolute logarithmic height. For a nonidentity point
, put
, with
. The canonical height, also called the Néron-Tate
height, is
It differs from
by a bounded function but satisfies the exact quadratic relation
. Over a number
field,
if and only if
is a torsion point.
The associated Néron-Tate height pairing is
It induces a positive definite inner product on the group of -rational points modulo torsion. The Gross-Zagier
formula expresses a derivative of a Rankin L-series
in terms of such a height.