Relative-Zeta and Casimir energy for a semitransparent hyperplane selecting transverse modes
arXiv:1702.05296 · doi:10.1007/978-3-319-58904-6_5
Abstract
We study the relative zeta function for the couple of operators and , where is the free unconstrained Laplacian in () and is the singular perturbation of associated to the presence of a delta interaction supported by a hyperplane. In our setting the operatorial parameter , which is related to the strength of the perturbation, is of the kind , where is the free Laplacian in . Thus may depend on the components of the wave vector parallel to hyperplane; in this sense describes a semitransparent hyperplane selecting transverse modes. As an application we give an expression for the associated thermal Casimir energy. Whenever , where is the characteristic function of an interval , the thermal Casimir energy can be explicitly computed.
21 pages