posted on 2017-04-12, 08:40authored byHamid Abban, Ivan Cheltsov, Josef Schicho
We study Tian’s α-invariant in comparison with the α1-invariant for pairs (Sd, H) consisting of a smooth surface Sd of degree d in the projective three-dimensional space and a hyperplane section H. A conjecture of Tian asserts that α(Sd, H) = α1(Sd, H). We show that this is indeed true for d = 4 (the result is well known for d 6 3), and we show that α(Sd, H) < α1(Sd, H) for d > 8 provided that Sd is general enough. We also construct examples of Sd, for d = 6 and d = 7, for which Tian’s conjecture fails. We provide a candidate counterexample for S5.
History
School
Science
Department
Mathematical Sciences
Published in
Mathematische Zeitschrift
Citation
AHMADINEZHAD, H., CHELTSOV, I. and SCHICHO, J., 2017. On a conjecture of Tian. Mathematische Zeitschrift, 288 (1-2), pp.217–241.
This work is made available according to the conditions of the Creative Commons Attribution 4.0 International (CC BY 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by/4.0/
Acceptance date
2017-03-20
Publication date
2017
Notes
This is an Open Access Article. It is published by Springer under the Creative Commons Attribution 4.0 Unported Licence (CC BY). Full details of this licence are available at: http://creativecommons.org/licenses/by/4.0/