Paper · May 5, 2023

Deformations of Fano manifolds with weighted solitons

Akito Futaki

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Abstract

We consider weighted solitons on Fano manifolds which include Kaehler-Ricci solitons, Mabuchi solitons and base metrics which induce Calabi-Yau cone metrics outside the zero sections of the canonical line bundles (Sasaki-Einstein metrics on the associated -bundles). In this paper, we give a condition for a weighted soliton on a Fano manifold to extend to weighted solitons on small deformations of the Fano manifold . More precisely, we show that all the members of the Kuranishi family of a Fano manifold with a weighted soliton have weighted solitons if and only if the dimensions of -equivariant automorphism groups of are equal to that of , and also if and only if the -equivariant automorphism groups of are all isomorphic to that of , where the weight functions are defined on the moment polytope of the Hamiltonian -action. This generalizes a result of Cao-Sun-Yau-Zhang for Kaehler-Einstein metrics.

Comments: Modified along the referee reports. References added. To appear in Pure and Applied Mathematics Quarterly

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  1. On weighted extremal Kähler metrics

    Akito Futaki PDF

    Topics Sasakian & contact geometry, Kähler–Einstein & K-stability, Kähler–Ricci solitons · Same author Akito Futaki · Shared terms “Sasaki Einstein”, “Calabi”

  2. From Kähler Ricci solitons to Calabi-Yau Kähler cones

    Vestislav Apostolov, Abdellah Lahdili and Eveline Legendre PDF

    Topics Ricci-flat & Calabi–Yau, Kähler–Einstein & K-stability, Kähler–Ricci solitons · Shared terms “Fano manifold”, “Yau cone”, “weight functions”

  3. Multiplier Hermitian-Einstein metrics on Fano manifolds of KSM-type

    Yasuhiro Nakagawa and Satoshi Nakamura PDF

    Topics Kähler–Einstein & K-stability, Kähler–Ricci solitons, Einstein metrics · Shared terms “Fano manifold”, “Mabuchi solitons”

  4. The weighted Hermite–Einstein equation

    Michael Hallam and Abdellah Lahdili PDF

    Topics Sasakian & contact geometry, Kähler–Ricci solitons, Einstein metrics · Shared terms “moment polytope”, “equivariant”, “weight functions”

  5. Extremal Kähler–Ricci solitons on Fano manifolds are Kähler–Einstein

    Yasufumi Nitta PDF

    Topics Kähler–Einstein & K-stability, Kähler–Ricci solitons, Einstein metrics · Shared terms “Fano manifold”

  6. On canonical radial Kaehler metrics

    Andrea Loi, Filippo Salis and Fabio Zuddas PDF

    Topics Kähler–Einstein & K-stability, Kähler–Ricci solitons, Einstein metrics · Shared terms “Kaehler”

  7. Log del Pezzo -surfaces, Kähler-Einstein metrics, Kähler-Ricci solitons and Sasaki-Einstein metrics

    Daniel Hättig, Jürgen Hausen and Hendrik Süß PDF

    Topics Sasakian & contact geometry, Kähler–Einstein & K-stability, Kähler–Ricci solitons · Shared terms “Sasaki Einstein”

  8. Explicit complete Ricci-flat metrics and Kähler-Ricci solitons on direct sum bundles

    Charles Cifarelli PDF

    Topics Ricci-flat & Calabi–Yau, Kähler–Einstein & K-stability, Kähler–Ricci solitons · Shared terms “Fano manifold”, “Cao”, “Hamiltonian”

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