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Larsen’s conjecture: infinite rank over K(σ) for each σ

Prove that if K is an infinite finitely generated field and e ≥ 1, then for every σ in G_K^e and every abelian variety A of positive dimension over K(σ), the Mordell–Weil group A(K(σ)) has rank ℵ₀.

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Background

Theorem 3.1(1) asserts that for almost all σ in G_Ke the rank is ℵ₀. Larsen conjectured that the same holds for every σ (not just almost all). Im and Larsen proved the conjecture when e=1 and char(K)≠2, but the general case is open.

References

Larsen [Lar03] conjectured that the statement on the field K(o) in (1) holds for any o E GR.

Mordell--Weil groups over large algebraic extensions of fields of characteristic zero (2408.03495 - Asayama et al., 7 Aug 2024) in Section 3, following Theorem 3.1