## Illinois Journal of Mathematics

### Riemannian almost CR manifolds with torsion

#### Abstract

We characterize and study Riemannian almost CR manifolds admitting characteristic connections, that is, metric connections with totally skew-symmetric torsion parallelizing the almost CR structure. Natural constructions are provided of new nontrivial examples. We study the influence of the curvature of the metric on the underlying almost CR structure. A global classification is obtained under flatness assumption of a characteristic connection, provided that the fundamental $2$-form of the structure is closed (quasi Sasakian condition).

#### Article information

Source
Illinois J. Math., Volume 58, Number 3 (2014), 807-846.

Dates
Revised: 19 February 2015
First available in Project Euclid: 9 September 2015

https://projecteuclid.org/euclid.ijm/1441790391

Digital Object Identifier
doi:10.1215/ijm/1441790391

Mathematical Reviews number (MathSciNet)
MR3395964

Zentralblatt MATH identifier
1328.53036

#### Citation

Dileo, Giulia; Lotta, Antonio. Riemannian almost CR manifolds with torsion. Illinois J. Math. 58 (2014), no. 3, 807--846. doi:10.1215/ijm/1441790391. https://projecteuclid.org/euclid.ijm/1441790391

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