English
Related papers

Related papers: The harmonic $2$-forms on $K3$ surfaces converging…

200 papers

We obtain Ricci flat K\"ahler metrics on complex symmetric spaces of rank two by using an explicit asymptotic model whose geometry at infinity is interpreted in the wonderful compactification of the symmetric space. We recover the metrics…

Differential Geometry · Mathematics 2020-11-17 Olivier Biquard , Thibaut Delcroix

We characterise the actions, by holomorphic isometries on a K\"ahler manifold with zero first Betti number, of an abelian Lie group of dim\geq 2, for which the moment map is horizontally weakly conformal (with respect to some Euclidean…

Differential Geometry · Mathematics 2013-04-19 M. Benyounes , E. Loubeau , R. Pantilie

Motivated by understanding the limiting case of a certain systolic inequality we study compact Riemannian manifolds having all harmonic 1-forms of constant length. We give complete characterizations as far as K\"ahler and hyperbolic…

Differential Geometry · Mathematics 2008-10-10 Paul-Andi Nagy

In this paper, we investigate the asymptotic behavior of regular ends of flat surfaces in the hyperbolic 3-space H^3. Galvez, Martinez and Milan showed that when the singular set does not accumulate at an end, the end is asymptotic to a…

Differential Geometry · Mathematics 2009-08-03 Masatoshi Kokubu , Wayne Rossman , Masaaki Umehara , Kotaro Yamada

The symplectic reduction of a complete toric K\"ahler manifold need not be closed or even be a polygon. Sharp differences in behavior occur between those complete toric K\"ahler 4-manifolds with closed and with non-closed reductions. This…

Differential Geometry · Mathematics 2023-11-14 Brian Weber

We investigate the collapsing geometry of hyperk\"ahler 4-manifolds. As applications we prove two well-known conjectures in the field. (1) Any collapsed limit of unit-diameter hyperk\"ahler metrics on the K3 manifold is isometric to one of…

Differential Geometry · Mathematics 2023-01-02 Song Sun , Ruobing Zhang

Inspired by the work of Ou [12,17], we study biharmonic conformal immersions of surfaces into a conformally flat 3-space. We first give a characterization of biharmonic conformal immersions of totally umbilical surfaces into a generic…

Differential Geometry · Mathematics 2024-09-05 Ze-Ping Wang , Xue-Yi Chen

Abreu-Sena-Dias have constructed two distinct families of scalar-flat K\"ahler non-compact toric metrics using Donaldson's rephrasing of Joyce's construction in action-angle coordinates. In this paper and using the same set-up, we show that…

Differential Geometry · Mathematics 2020-10-07 Rosa Sena-Dias

Explicit solutions to the conifold equations with complex dimension $n=3,4$ in terms of {\it{complex coordinates (fields)}} are employed to construct the Ricci-flat K\"{a}hler metrics on these manifolds. The K\"{a}hler 2-forms are found to…

High Energy Physics - Theory · Physics 2009-11-07 R. Parthasarathy , K. S. Viswanathan

We exhibit families of Ricci-flat Kahler metrics on K3 surfaces which collapse to an interval, with Tian-Yau and Taub-NUT metrics occurring as bubbles. There is a corresponding continuous surjective map from the K3 surface to the interval,…

Differential Geometry · Mathematics 2018-07-26 Hans-Joachim Hein , Song Sun , Jeff Viaclovsky , Ruobing Zhang

We consider $G_2$-manifolds with an effective torus action that is multi-Hamiltonian for one or more of the defining forms. The case of $T^3$-actions is found to be distinguished. For such actions multi-Hamiltonian with respect to both the…

Differential Geometry · Mathematics 2020-01-08 Thomas Bruun Madsen , Andrew Swann

In general, the product of harmonic forms is not harmonic. We study the top exterior power of harmonic two-forms on compact Kaehler manifolds. Often, it is not harmonic. This phenomenon is related to the geometry of the manifold and to the…

Algebraic Geometry · Mathematics 2007-05-23 D. Huybrechts

The two dimensional set of canonical relations giving rise to minimal uncertainties previously constructed from a q-deformed oscillator algebra is further investigated. We provide a representation for this algebra in terms of a flat…

High Energy Physics - Theory · Physics 2013-07-04 Sanjib Dey , Andreas Fring

For $U(2)$-invariant 4-metrics, we show that the $B^t$-flat metrics are very different from the other canonical metrics (Bach-flat, Einstein, extremal K\"ahler, etc). We show every $U(2)$-invariant metric is conformal to two separate…

Differential Geometry · Mathematics 2023-09-04 Keaton Naff , Brian Weber

We exhibit many examples of closed symplectic manifolds on which there is an autonomous Hamiltonian whose associated flow has no nonconstant periodic orbits (the only previous explicit example in the literature was the torus T^2n (n\geq 2)…

Symplectic Geometry · Mathematics 2014-09-10 Michael Usher

In this paper we study the gradient steady K\"ahler-Ricci soliton metrics on non-compact toric manifolds. We show that the orbit space of the free locus of such a manifold carries a natural Hessian structure with a nonnegative Bakry-\'Emery…

Differential Geometry · Mathematics 2022-06-16 Yury Ustinovskiy

Using the twistor correspondence, this article gives a one-to-one correspondence between germs of toric anti-self-dual conformal classes and certain holomorphic data determined by the induced action on twistor space. Recovering the metric…

Differential Geometry · Mathematics 2017-04-26 Simon K. Donaldson , Joel Fine

We search for Ricci flat, K\"{a}hler geometries which are asymptotic to the cone whose base is the space T^{11} by working out covariantly constant spinor equations. The metrics we find are singular in the interior and introducing parallel…

High Energy Physics - Theory · Physics 2009-11-07 Ali Kaya

We discuss a technique to construct Ricci-flat hermitian metrics on complements of (some) anticanonical divisors of almost homogeneous manifolds and discuss when this metric is complete and K\"ahler. This construction has a strong interplay…

Differential Geometry · Mathematics 2007-05-23 Bert Koehler , Marco Kuehnel

We discuss the geometry and topology of the complete, non-compact, Ricci-flat Stenzel metric, on the tangent bundle of S^{n+1}. We obtain explicit results for all the metrics, and show how they can be obtained from first-order equations…

High Energy Physics - Theory · Physics 2009-10-31 M. Cvetic , G. W. Gibbons , H. Lu , C. N. Pope