arXiv research

New conformally invariant forms help identify Einstein metrics.

The paper examines $(α,β)$-metrics and proves they are Berwald metrics under certain conditions.

We discuss the Morse-Novikov cohomology of a compact manifold, associated to a closed one--form whose free abelian group generated by its periods $\langle \int_γη\mid [γ] \in π_1(M)\rangle$ is of rank 1, the focus being on locally conformally symplectic manifolds. In particular, we provide an explicit computation for t…

A locally conformally symplectic (LCS) form is an almost symplectic form $ω$ such that a closed one-form $θ$ exists with $dω= θ\wedge ω$. We present a version of the well-known result of Darboux and Weinstein in the LCS setting and give an application concerning Lagrangian submanifolds.

It is shown that an HKT-space with closed parallel potential 1-form has $D(2,1;-1)$-symmetry. Every locally conformally hyperkähler manifold generates this type of geometry. The HKT-spaces with closed parallel potential 1-form arising in this way are characterized by their symmetries and an inhomogeneous cubic conditio…

Study Schiffer operators on Riemann surfaces, linking conformal and topological invariants.

Geodesic X-ray transform proves injective for smooth one-forms on gas giant manifolds.

Unique continuation for X-ray transforms of one-forms with partial data.

Scattering theory for harmonic one-forms on Riemann surfaces.

The paper explores scaling symmetries in symplectic geometry and their applications to central configurations.

In the present paper, we consider the Hodge-de Rham Laplacian that acts on conformal Killing and projective Killing one-forms of a compact Riemannian manifold.

Unified approach to conformal and modular invariants on surfaces.

A locally conformally symplectic (LCS) form is an almost symplectic form $ω$ such that a closed one-form $θ$ exists with $dω=θ\wedgeω$. A fiber bundle with LCS fiber $(F, ω,θ)$ is called LCS if the transition maps are diffeomorphisms of $F$ preserving $ω$ (and hence $θ$). In this paper, we find conditions for the total…

The paper introduces a trilinear functional to recover torsion in spectral triples.

In the Cauchy problem for asymptotically flat vacuum data the solution-jets along the cylinder at space-like infinity develop in general logarithmic singularities at the critical sets at which the cylinder touches future/past null infinity. The tendency of these singularities to spread along the null generators of null…

We construct a conformally invariant vector bundle connection such that its equation of parallel transport is a first order system that gives a prolongation of the conformal Killing equation on differential forms. Parallel sections of this connection are related bijectively to solutions of the conformal Killing equatio…

An anologue of the Calabi invariant for Poisson manifolds is considered. For any Poisson manifold $P$, the Poisson bracket on $C^{\infty}(P)$ extends to a Lie bracket on the space $Ω^{1}(P)$ of all differential one-forms, under which the space $Z^{1}(P)$ of closed one-forms and the space $B^{1}(P)$ of exact one-forms a…

Simplified proof of Cerf's theorem on 3-sphere diffeomorphisms.

This paper derives an explicit formula for Branson's Q-curvature in even-dimensional conformal geometry. The ingredients in the formula come from the Poincare metric in one higher dimension; hence the formula is called holographic. When specialized to the conformally flat case, the holographic formula expresses Q-curva…

Study shows equivalence between cohomology class existence and polynomial properties for 3D manifolds.

Abstract: Expresses zeta-determinant of Dirichlet-to-Neumann operator on forms.

We consider systems $(M,ω,g)$ with $M$ a closed smooth manifold, $ω$ a real valued closed one form and $g$ a Riemannian metric, so that $(ω,g)$ is a Morse-Smale pair, Definition~2. We introduce a numerical invariant $ρ(ω,g)\in[0,\infty]$ and improve Morse-Novikov theory by showing that the Novikov complex comes from a …

Proves spectrum of Laplacian on forms over flat manifolds is a connected interval.

New proof confirms periodic orbit conjecture for Eulerisable flows.

Short note proves Poincaré inequality for 4-manifold forms.

The paper characterizes ambient metrics using conformal completion and null infinity properties.

Generalizes Fefferman's structure to CR three-manifolds with additional data.

The current article studies certain problems related to complex cycles of holomorphic foliations with singularities in the complex plane. We focus on the case when polynomial differential one-form gives rise to a foliation by Riemann surfaces. In this setting, a complex cycle is defined as a nontrivial element of the f…

Classifies low-energy harmonic maps from curved surfaces to spheres.

For even dimensional conformal manifolds several new conformally invariant objects were found recently: invariant differential complexes related to, but distinct from, the de Rham complex (these are elliptic in the case of Riemannian signature); the cohomology spaces of these; conformally stable form spaces that we may…

We consider a vector field $X$ on a closed manifold which admits a Lyapunov one form. We assume $X$ has Morse type zeros, satisfies the Morse--Smale transversality condition and has non-degenerate closed trajectories only. For a closed one form $η$, considered as flat connection on the trivial line bundle, the differen…

Solves Calabi-Yau equation on symplectic manifolds using measurable Kahler metrics.

The paper examines parallel one forms on Riemannian and Finslerian manifolds.

Completes the space of vector-valued one-forms on manifolds.

Study quadratic one-forms on logarithmic Higgs bundles on pointed curves.

Paper verifies a conjecture about Kähler manifolds and holomorphic one-forms.

Study vortex loops as coadjoint orbits of diffeomorphisms.

The paper discusses properties of holomorphic one-forms on certain complex manifolds.

We consider 2-dimensional orientable self-shrinkers $Σ$ for the Mean Curvature Flow of polynomial volume growth immersed in $\mathbb R^n$. We look at closed one forms minimizing the norm $\int_Σ\eterm |ω|^2$ in their cohomology class. Any closed form satisfying the Euler-Lagrange equation for this minimization will be …

The paper defines vector 1-forms on Finsler manifolds and constructs connections.

Study rigid Lie affine foliations on compact manifolds.

The paper studies harmonic symmetric bilinear forms on Riemannian manifolds and proves properties of the Bourguignon Laplacian.

We present two range characterizations for the attenuated geodesic X-ray transform defined on pairs of functions and one-forms on simple surfaces. Such characterizations are based on first isolating the range over sums of functions and one-forms, then separating each sub-range in two ways, first by implicit conditions,…

The subject of this paper is the relationship among the marked length spectrum, the length spectrum, the Laplace spectrum on functions, and the Laplace spectrum on forms on Riemannian nilmanifolds. In particular, we show that for a large class of three-step nilmanifolds, if a pair of nilmanifolds in this class has the …

The subject of this paper is the relationship among the marked length spectrum, the length spectrum, the Laplace spectrum on functions, and the Laplace spectrum on forms on Riemannian nilmanifolds. In particular, we show that for a large class of three-step nilmanifolds, if a pair of nilmanifolds in this class has the …

New spectral torsion defined for rescaled Dirac operators.

Given a Lorentzian manifold $(M,g_L)$ and a timelike unitary vector field $E$, we can construct the Riemannian metric $g_R=g_L+2ω\otimesω$, being $ω$ the metrically equivalent one form to $E$. We relate the curvature of both metrics, especially in the case of $E$ being Killing or closed, and we use the relations obtain…

Study proves Kotschick's conjecture for certain compact Kähler manifolds.