Research Interests
My area of research is differential geometry, geomteric analysis and gauge theory. I particularly think about
- manifolds with special geometric structures
- moduli spaces of instantons on special manifolds
- deformation theory of special algebraic structures
Preprints
- A $\mathrm{dd}^\Phi$-Lemma and Bott-Chern-type Cohomology for Spin(7)-Manifolds (with Shubham Dwivedi), arXiv
Abstract
We study the properties of the $\mathrm{dd}^\Phi$-operator on $8$-dimensional Spin(7)-manifolds with torsion-free Spin(7)-structures $\Phi$. These operators were first introduced in our previous work on nearly parallel G$_2$-structures and their potential deformations. Our main result is a $\mathrm{dd}^\Phi$-Lemma for torsion-free Spin(7)-structures. As an application, we define a new Bott-Chern type cohomology theory, which we compare with Dolbeault and Bott-Chern cohomologies. We also show that a formal deformation of a torsion-free Spin(7)-structure is obstructed by a class in the defined Bott-Chern cohomology.
- Solutions and singularities of the Ricci-harmonic flow and Ricci-like flows of G2-structures (with Shubham Dwivedi), arXiv
Abstract
We find explicit solutions and singularities of the Ricci-harmonic flow of G2-structures, the Ricci-like flows of G2-structures studied by Gianniotis-Zachos, and the pluriclosed flow on nearly parallel G2 structures. For the Ricci-harmonic flow, we show that the Berard-Bergery solution on $\mathbb{R}^7$ is a backward self-similar solution and has a type I blowup singularity. We show that any finite time singularity in the Ricci-harmonic flow of G2-structures with nonnegative Ricci curvature must be of type I. We also exhibit a type II blowup singularity for the Ricci-like flow. Finally, we show that the pluriclosed flow on the homogeneous nearly parallel G2 structure (the Aloff-Wallach space $N_{k,l}$) exists for all time and converges to a nearly parallel G2 structure.
Published articles
- Examples of real stable bundles on K3 surfaces (with Dino Festi, Daniel Platt, Shizhuo Zhang), arXiv, Accepted for publication in Mathematische Zeitschrift
Abstract
Motivated by gauge theory on manifolds with exceptional holonomy, we construct examples of stable bundles on K3 surfaces that are invariant under two involutions: one is holomorphic and the other is anti-holomorphic. We use our construction to produce examples of G2 instantons on the Caldararu-Dominic G2 manifold. We also produce stable bundles that are invariant under the involution defined by antiholomorphic automorphisms via moduli.
- Revisting 3-Sasakian and G2 structures (with Simon Salamon), Real and Complex Geometry, special edition on the occasion of Paul Gauduchon's 80th birthday
arXiv Journal
Abstract
The algebra of exterior differential forms on a regular 3-Sasakian 7-manifold is investigated, with special reference to nearly-parallel G2 3-forms. This is applied to obtain new information about the homogeneous 3-Sasakian structures N_{k,l} of Aloff and Wallach, and the quaternion Kahler orbifold $\mathbb{HP}^n/C_m$ which underlies each such structure. We construct nearly parallel G2-structures on all N_{k,l} and show that these induce 3-Sasakian structures on $\mathbb{HP}^n /C_m$.
- Nearly half-flat SU(3)-structures on S3×S3, Differential Geometry and Its Applications, Volume 97 (2024) arXiv Journal
Abstract
We study the SU(3)-structure induced on an oriented hypersurface of a 7-dimensional manifold with a nearly parallel G2-structure. We call such SU(3)-structures nearly half-flat, and we classify the space of such structures on S3 × S3. We also study the deformations of nearly half-flat SU(3)-structures and compute their deformation space.
- Deformation theory of nearly G2 manifolds (with Shubham Dwivedi), Communications in Analysis and Geometry, Volume 31 (2023) arXiv Journal
Abstract
- Deformations of G2 instantons on nearly G2 manifolds, Annals of Global Analysis and Geometry, Volume 62 (2022) arXiv Journal
Abstract
Thesis
- Deformation theory of nearly G2-structures and nearly G2 instantons, PhD thesis, University of Waterloo (2021) Thesis