arXiv subjects

Yassin Chebbi

Publications and source records attributed to Yassin Chebbi.

3 recordsLinked to original sources

arXiv2021

Self-adjointness of magnetic laplacians on triangulations

The notions of magnetic difference operator defined on weighted graphs or magnetic exterior derivative are discrete analogues of the notionof covariant derivative on sections of a fibre bundle and its extension on differential forms. In this paper, we extend this notion to certain 2-simplicial complexes called triangulations, in a manner compatible with changes of gauge. Then we study the magnetic Gauss-Bonnet operator naturally defined in this context and introduce the geometric hypothesis of $\chi-$completeness which ensures the essential self-adjointness of this operator. This gives also the essential self-adjointness of the magnetic Laplacian on triangulations. Finally we introduce an hypothesis of bounded curvature for the magnetic potential which permits to characterize the domain of the self-adjoint extension.

math.CO↗

arXiv2019

Spectral Gap of The Discrete Laplacian On Triangulations

Our goal in this paper is to find an estimate for the spectral gap of the Laplacian on a 2-simplicial complex consisting on a triangulation of a complete graph. An upper estimate is given by generalizing the Cheeger constant. The lower estimate is obtained from the first non-zero eigenvalue of the discrete Laplacian acting on the functions of certain sub-graphs.

math.SP↗

arXiv2018

The discrete Laplacian of a 2-simplicial complex

In this paper, we introduce the notion of oriented faces especially triangles in a connected oriented locally finite graph. This framework then permits to define the Laplace operator on this structure of the 2-simplicial complex. We develop the notion of $\chi$-completeness for the graphs, based on the cutoff functions. Moreover, we study essential self-adjointness of the discrete Laplacian from the $\chi$-completeness geometric hypothesis.

math.SP↗