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Fat point modules from ruling-two lines for S and T

Ascertain whether, for each component C_i (1 ≤ i ≤ 10) of the line scheme of the algebras S or T, every line ℓ lying in the second ruling ℛ_{i,2} of the associated smooth quadric Q_i in P^3 and not contained in any ruling-one family ℛ_{j,1}, yields a truncated module F(ℓ) = [M(ℓ)(1)]_{≥1} that is always a fat point module of multiplicity two over the corresponding algebra (S or T).

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Background

For the AS regular algebras S and T constructed in the paper, each line-scheme component C_i corresponds to a smooth quadric Q_i in P3, with two rulings; only one ruling produces line modules. The other ruling empirically appears to produce fat point modules of multiplicity two.

The question asks to verify this phenomenon uniformly for all ruling-two lines not in any ruling-one family, establishing a systematic connection between these geometric lines and fat point modules.

References

Question Let \ell \in {\mathcal{R}{i,2} and assume that \ell \notin {\mathcal{R}{j, 1} for any 1 \leq j \leq 10. Is F(\ell) always a fat point module of multiplicity two?

Some Artin-Schelter Regular Algebras From Dual Reflection Groups and their Geometry (2410.08959 - Goetz et al., 11 Oct 2024) in Section 6.2 (Rulings on quadrics and fat points)