title: Theory of Casimir Forces without the Proximity-Force Approximation.
abstract: We analyze both the attractive and repulsive Casimir-Lifshitz forces recently reported in experimental investigations. By using a kinetic approach, we obtain the Casimir forces from the power absorbed by the materials. We consider collective material excitations through a set of relaxation times distributed in frequency according to a log-normal function. A generalized expression for these forces for arbitrary values of temperature is obtained. We compare our results with experimental measurements and conclude that the model goes beyond the proximity-force approximation.
authors.affiliation: Interdisciplinary Center for Natural Sciences, UNILA, P.O. Box 2067, 85867-970 Foz do Iguaçu, Brazil.
authors.forename: Luciano C
authors.initials: LC
authors.lastname: Lapas
authors.affiliation: Departament de Física Fonamental, Facultat de Física, Universitat de Barcelona, Avinguda Diagonal 647, 08028 Barcelona, Spain.
authors.forename: Agustín
authors.initials: A
authors.lastname: Pérez-Madrid
authors.affiliation: Departament de Física Fonamental, Facultat de Física, Universitat de Barcelona, Avinguda Diagonal 647, 08028 Barcelona, Spain.
authors.forename: J Miguel
authors.initials: JM
authors.lastname: Rubí