28 research outputs found
A Hamiltonian stable minimal Lagrangian submanifold of projective space with non-parallel second fundamental form
In this note we show that Hamiltonian stable minimal Lagrangian submanifolds
of projective space need not have parallel second fundamental form.Comment: 7 page
Actions of vanishing homogeneity rank on quaternionic-Kaehler projective spaces
We classify isometric actions of compact Lie groups on quaternionic-K\"ahler
projective spaces with vanishing homogeneity rank. We also show that they are
not in general quaternion-coisotropic.Comment: 18 pages. The present version corrects and improves the previous
version of the paper entitled "3-coisotropic actions on positive
quaternionic-Kaehler manifolds". A key example has been adde
A parabolic flow of balanced metrics
We prove a general criterion to establish existence and uniqueness of a
short-time solution to an evolution equation involving "closed" sections of a
vector bundle, generalizing a method used recently by Bryant and Xu for
studying the Laplacian flow in G_2-geometry. We apply this theorem in balanced
geometry introducing a natural extension of the Calabi flow to the balanced
case. We show that this flow has always a unique short-time solution belonging
to the same Bott-Chern cohomology class of the initial balanced structure and
that it preserves the Kaehler condition. Finally we study explicitly the flow
on the Iwasawa manifold.Comment: 19 pages. Revised version. To appear in Crelle's Journa
On the stability of the anomaly flow
We prove that the parabolic flow of conformally balanced metrics introduced
by Phong, Picard and Zhang in "A flow of conformally balanced metrics with
Kaehler fixed points", is stable around Calabi-Yau metrics. The result shows
that the flow can converge on a Kaehler manifold even if the initial metric is
not conformally Kaehler.Comment: 10 pages. Major revision, to appear in Math. Res. Let
A remark on the Laplacian flow and the modified Laplacian co-flow in G2-Geometry
We observe that the DeTurck Laplacian flow of G2-structures introduced by
Bryant and Xu as a gauge fixing of the Laplacian flow can be regarded as a flow
of G2-structures (not necessarily closed) which fits in the general framework
introduced by Hamilton in [4].Comment: 3 pages, comments are welcom