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Related papers: Global secondary CR invariants in dimension five

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Q-prime curvature, which was introduced by J. Case and P. Yang, is a local invariant of pseudo-hermitian structure on CR manifolds that can be defined only when the Q-curvature vanishes identically. It is considered as a secondary invariant…

Complex Variables · Mathematics 2014-02-04 Kengo Hirachi

For each invariant polynomial $\Phi$, we construct a global CR invariant via the renormalized characteristic form of the Cheng--Yau metric on a strictly pseudoconvex domain. When the degree of $\Phi$ is 0, the invariant agrees with the…

Differential Geometry · Mathematics 2020-11-16 Taiji Marugame

We study a global invariant for path structures. The invariant is obtained as a secondary invariant from a Cartan connection on a canonical bundle associated to a path structure. It is computed in examples which are defined in terms of…

Differential Geometry · Mathematics 2023-07-03 Elisha Falbel , Jose Miguel Veloso

Let $\mathrm S^3$ be the unit sphere of $\mathbb C^2$ with its standard Cauchy-Riemann (CR) structure. This paper investigates the CR geometry of curves in $\mathrm S^3$ which are transversal to the contact distribution, using the local CR…

Differential Geometry · Mathematics 2021-01-01 Emilio Musso , Lorenzo Nicolodi , Filippo Salis

In this paper we compute the first and second variation of the normalized Einstein-Hilbert functional on CR manifolds. We characterize critical points as pseudo-Einstein structures. We then turn to the second variation on standard spheres.…

Differential Geometry · Mathematics 2023-06-14 Claudio Afeltra , Jih-Hsin Cheng , Andrea Malchiodi , Paul Yang

We study two kinds of curvature invariants of Riemannian manifold equip\-ped with a complex distribution $D$ (for example, a CR-submanifold of an almost Hermitian manifold) related to sets of pairwise orthogonal subspaces of the…

Differential Geometry · Mathematics 2024-08-30 Mirjana Djorić , Vladimir Rovenski

The $Q$-prime curvature is a local pseudo-Einstein invariant on CR manifolds defined by Case and Yang, and Hirachi. Its integral, the total $Q$-prime curvature, gives a non-trivial global CR invariant. On the other hand, Marugame has…

Differential Geometry · Mathematics 2023-09-07 Yuya Takeuchi

We extend the notions of CR GJMS operators and Q-curvature to the case of partially integrable CR structures. The total integral of the CR Q-curvature turns out to be a global invariant of compact nondegenerate partially integrable CR…

Differential Geometry · Mathematics 2015-03-03 Yoshihiko Matsumoto

The Q-curvature has been playing a central role in conformal geometry since its discovery by T. Branson. It has natural analogy in CR geometry, however, the CR Q-curvature vanishes on the boundary of a strictly pseudoconvex domain in…

Differential Geometry · Mathematics 2016-11-11 Kengo Hirachi

In this paper, we give explicit formulae of the Burns-Epstein invariant and global CR invariants via renormalized characteristic forms introduced by Marugame for Sasakian $\eta$-Einstein manifolds. As an application, we show that the latter…

Differential Geometry · Mathematics 2025-02-17 Yuya Takeuchi

On a compact Kahler manifold, one can define global invariants by integrating local invariants of the metric. Assume that a global invariant thus obtained depends only on the Kahler class. Then we show that the integrand can be decomposed…

Differential Geometry · Mathematics 2017-01-04 Spyros Alexakis , Kengo Hirachi

We construct higher-dimensional analogues of the $\mathcal{I}^\prime$-curvature of Case and Gover in all CR dimensions $n\geq2$. Our $\mathcal{I}^\prime$-curvatures all transform by a first-order linear differential operator under a change…

Differential Geometry · Mathematics 2020-03-19 Jeffrey S. Case , Yuya Takeuchi

In this paper, we study on semi-invariant submanifolds of normal complex contact metric manifolds. We give the definition of such submanifolds and we obtain useful relations. Moreover, we give the integrability conditions of distributions.

Differential Geometry · Mathematics 2020-08-05 Aysel Turgut Vanli , Inan Unal

New invariants for 2-dimensional cell complexes are defined, which can be interpreted as curvature bounds. These invariants are proved to be rational and computable in a companion article. This document is a survey that collects theorems…

Group Theory · Mathematics 2024-05-16 Henry Wilton

We introduce two invariants called the secondary cuspidal curvature and the bias on $5/2$-cuspidal edges, and investigate their basic properties. While the secondary cuspidal curvature is an analog of the cuspidal curvature of (ordinary)…

Differential Geometry · Mathematics 2019-02-19 Atsufumi Honda , Kentaro Saji

We reduce CR-structures on smooth elliptic and hyperbolic manifolds of CR-codimension 2 to parallelisms thus solving the problem of global equivalence for such manifolds. The parallelism that we construct is defined on a sequence of two…

Complex Variables · Mathematics 2007-05-23 V. V. Ezhov , A. V. Isaev , G. Schmalz

A pseudo-Einstein contact form plays a crucial role in defining some global invariants of closed strictly pseudoconvex CR manifolds. In this paper, we prove that the existence of a pseudo-Einstein contact form is preserved under…

Differential Geometry · Mathematics 2020-01-22 Yuya Takeuchi

We show that any contact form whose Fefferman metric admits a nonzero parallel vector field is pseudo-Einstein of constant pseudohermitian scalar curvature. As an application we compute the curvature groups of the total space of the…

Differential Geometry · Mathematics 2007-05-23 Elisabetta Barletta , Sorin Dragomir

This is the fourth in a series of papers where we prove a conjecture of Deser and Schwimmer regarding the algebraic structure of ``global conformal invariants''; these are defined to be conformally invariant integrals of geometric scalars.…

Differential Geometry · Mathematics 2009-12-21 Spyros Alexakis

In the present paper, we study globally framed f-manifolds in the particular setting of indefinite S-manifolds for both spacelike and timelike cases. We prove that if $M = N^{\perp} \times_f N^T$ is a warped CR-submanifold such that…

Differential Geometry · Mathematics 2012-04-30 Khushwant Singh , S. S. Bhatia
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