>>277
南出論文
楕円曲線 “y2 = x(x-1)(x-λ)”
the Legendre form
“λ-line”
ここらが重要キーワードですね

http://www.kurims.kyoto-u.ac.jp/~motizuki/Explicit%20estimates%20in%20IUTeich.pdf
Explicit Estimates in Inter-universal Teichmuller Theory. PDF NEW!! (2020-11-30) いわゆる南出論文
P2
Introduction

Theorem.
7We shall regard X as the “λ-line” - i.e.,
we shall regard the standard coordinate on X as the “λ” in the Legendre
form “y2 = x(x-1)(x-λ)” of the Weierstrass equation defining an elliptic
curve -

P34
Corollary 5.2. (Construction of suitable µ6-initial Θ-data) Write X
for the projective line over Q; D ⊆ X for the divisor consisting of the
three points “0”, “1”, and “∞”; (Mell)Q for the moduli stack of elliptic
curves over Q. We shall regard X as the “λ-line” - i.e., we shall regard
the standard coordinate on X as the “λ” in the Legendre form “y2 =x(x - 1)(x - λ)” of the Weierstrass equation defining an elliptic curve -