Beltrametti–Sommese conjecture on effective strictly nef divisors

At least 18 years old · documented by

Let XX be a smooth projective variety and let DD be an effective strictly nef divisor on XX. A divisor DD is strictly nef if D⋅C>0D\cdot C>0 for every curve CC on XX.

Beltrametti–Sommese conjecture. If D−KXD-K_X is nef, then DD is ample.

This conjecture concerns when numerical positivity of an effective divisor, together with positivity relative to the canonical divisor, forces ampleness. The source presents it as a conjecture of Beltrametti and Sommese; no resolution is given in the supplied text.

References

Primary source

Nikolaos Tsakanikas and Zhixin Xie, “Comparison and uniruledness of asymptotic base loci”, arXiv:2309.01031 (2024).

Additional references

10 papers in this index state this conjecture (2007–2023). The statement above is taken from the most recent of them; the others are arXiv:2306.06985, arXiv:1307.1449, arXiv:1302.1413, arXiv:1105.2415, arXiv:1001.2792, arXiv:0912.1295, arXiv:0910.2785, arXiv:0811.3059, arXiv:0707.4140.

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.