91 citations · 424 across the 32 of their papers we have counts for
32 papers · 1 filter
Montel's theorem and tautness in calibrated geometry
Anton Iliashenko, Spiro Karigiannis, Jesse Madnick
We relate the hyperbolicity of a calibrated manifold to the analytic properties of the space of Smith immersions from the Poincare -ball into $X…
Flows of conformally coclosed -structures with dilaton
Spiro Karigiannis, Sébastien Picard, Caleb Suan
We study flows of -structures guided by the principle of dimensional reduction: natural geometric flows in -geometry reduce to natural flows in complex geometry. Our main…
Non-squeezing and capacities for some calibrated geometries
Kain Dineen, Spiro Karigiannis
It was shown by Barron--Shafiee that an analogue of Gromov's non-squeezing theorem holds for affine maps which preserve a power of the symplectic form on $\mathbb{R}^{2n}…
Holomorphicity of parabolic stable minimal surfaces of high codimension
Da Rong Cheng, Spiro Karigiannis, Jesse Madnick
A classical theorem of Micallef says that if is a stable minimal immersion of an oriented -dimensional complete Riemannian manifold (that is p…
Hodge theoretic results for nearly Kähler manifolds in all dimensions
Michael Albanese, Spiro Karigiannis, Lucía Martín-Merchán +1
We generalize to nearly Kähler manifolds of arbitrary dimensions most of the Hodge-theoretic results for nearly Kähler -manifolds that were established by Verbitsky. In particul…
BRIDGES Lectures: Flows of geometric structures, especially -structures
Spiro Karigiannis
The BRIDGES meeting in gauge theory, extremal structures, and stability was held June 2024 at l'Institut d'Études Scientifiques de Cargèse in Corsica, organized by Daniele Faenzi,…
Cohomogeneity one solitons for the isometric flow of -structures
Thomas A. Ivey, Spiro Karigiannis
We consider the existence of cohomogeneity one solitons for the isometric flow of -structures on the following classes of torsion-free -manifolds: the Euclidean wit…
A special class of -harmonic maps inducing calibrated fibrations
Anton Iliashenko, Spiro Karigiannis
We consider two special classes of -harmonic maps between Riemannian manifolds which are related to calibrated geometry, satisfying a first order fully nonlinear PDE. The first…
Flows of -structures, II: Curvature, torsion, symbols, and functionals
Shubham Dwivedi, Panagiotis Gianniotis, Spiro Karigiannis
We continue the investigation of general geometric flows of -structures initiated by the third author in "Flows of -structures, I." Specifically, we determine the possibl…
Extrinsic geometry of calibrated submanifolds
Spiro Karigiannis, Lucía Martín-Merchán
Given a calibration whose stabilizer acts transitively on the Grassmanian of calibrated planes, we introduce a nontrivial Lie-theoretic condition on , which we call complian…
Calibrated Geometry in Hyperkahler Cones, 3-Sasakian Manifolds, and Twistor Spaces
Benjamin Aslan, Spiro Karigiannis, Jesse Madnick
We systematically study calibrated geometry in hyperkähler cones , their 3-Sasakian links , and the corresponding twistor spaces , emphasizing the rel…
Observations about the Lie algebra , associative -planes, and subalgebras
Max Chemtov, Spiro Karigiannis
We make several observations relating the Lie algebra , associative -planes, and subalgebras. Some are likely well-kn…
A variational characterization of calibrated submanifolds
Da Rong Cheng, Spiro Karigiannis, Jesse Madnick
Let be a fixed compact oriented embedded submanifold of a manifold . Consider the volume as a function…
Twisted-Austere Submanifolds in Euclidean Space
Thomas A. Ivey, Spiro Karigiannis
A twisted-austere -fold in consists of a -dimensional submanifold of together with a closed -form on such that the `twiste…
Bryant-Salamon manifolds and coassociative fibrations
Spiro Karigiannis, Jason D. Lotay
Bryant-Salamon constructed three 1-parameter families of complete manifolds with holonomy which are asymptotically conical to a holonomy cone. For eac…
Introduction to geometry
Spiro Karigiannis
These notes give an informal and leisurely introduction to geometry for beginners. A special emphasis is placed on understanding the special linear algebraic structu…
Bubble Tree Convergence of Conformally Cross Product Preserving Maps
Da Rong Cheng, Spiro Karigiannis, Jesse Madnick
We study a class of weakly conformal -harmonic maps, called associative Smith maps, from -manifolds into -manifolds that parametrize associative -folds in Riemannian $7…
A gradient flow of isometric structures
Shubham Dwivedi, Panagiotis Gianniotis, Spiro Karigiannis
We study a flow of structures which induce the same Riemannian metric which is the negative gradient flow of an energy functional. We prove Shi-type estimates for the torsion…
The -cohomology on compact torsion-free manifolds and an application to 'almost' formality
Ki Fung Chan, Spiro Karigiannis, Chi Cheuk Tsang
We study a cohomology theory , called the -cohomology, on compact torsion-free -manifolds. We show that f…
Cohomologies on almost complex manifolds and the -lemma
Ki Fung Chan, Spiro Karigiannis, Chi Cheuk Tsang
We study cohomologies on an almost complex manifold , defined using the Nijenhuis-Lie derivations and induced from the almost complex struct…
A new construction of compact torsion-free -manifolds by gluing families of Eguchi-Hanson spaces
Dominic Joyce, Spiro Karigiannis
We give a new construction of compact Riemannian 7-manifolds with holonomy . Let be a torsion-free -manifold (which can have holonomy a proper subgroup of ) such…
Deformation theory of G_2 conifolds
Spiro Karigiannis, Jason Lotay
We consider the deformation theory of asymptotically conical (AC) and of conically singular (CS) -manifolds. In the AC case, we show that if the rate of convergence to the…
Deformations of calibrated subbundles of Euclidean spaces via twisting by special sections
Spiro Karigiannis, Nat Chun-Ho Leung
We extend the "bundle constructions" of calibrated submanifolds, due to Harvey--Lawson in the special Lagrangian case, and to Ionel--Karigiannis--Min-Oo in the cases of exceptional…
Soliton solutions for the Laplacian coflow of some -structures with symmetry
Spiro Karigiannis, Benjamin McKay, Mao-Pei Tsui
We consider the Laplacian "co-flow" of -structures: where is the dual 4-form of a -structure and is the Hodge Laplacian on forms.…