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Non-torsion degree-zero line bundles on abelian varieties are pt-ample (but not tensor-ample)

Prove that for any abelian variety A and any line bundle L of degree 0 with L^n ≄ O_A for all n>0, the induced polarization τ_L on Perf(A) is pt-ample while L is not ⊗-ample.

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Background

Motivated by the elliptic curve case, where non-torsion degree-zero line bundles yield pt-spectra equal to the tt-spectrum but are not ⊗-ample, the authors propose an abelian-variety-wide generalization.

This conjecture clarifies the difference between pt-ampleness and ⊗-ampleness in the context of polarizations and spectra.

References

Conjecture. Let $A$ be an abelian variety. Then, a line bundle $ L$ on $A$ of degree $0$ with $ L{\tens n} \not \iso O_A$ for any $n >0$ is pt-ample (but not $\tens$-ample).

Polarizations on a triangulated category (2502.15621 - Ito, 21 Feb 2025) in Section 4.1, Conjecture (end of “Reconstruction of varieties”)