title: Anomalous law of cooling.
abstract: We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergoes a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton's law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature may oscillate. Despite this anomalous behavior, we show that the variation of entropy remains always positive in accordance with the second law of thermodynamics.
authors.affiliation: Universidade Federal da Integração Latino-Americana, Caixa Postal 2067, 85867-970 Foz do Iguaçu, Paraná, Brazil.
authors.forename: Luciano C
authors.initials: LC
authors.lastname: Lapas
authors.affiliation: Centro de Ciências Exatas e Tecnológicas, Universidade Federal do Recôncavo da Bahia, 44380-000 Cruz das Almas, Bahia, Brazil.
authors.forename: Rogelma M S
authors.initials: RM
authors.lastname: Ferreira
authors.affiliation: Departament de Física Fonamental, Facultat de Física, Universitat de Barcelona, Av. Diagonal 647, 08028 Barcelona, Spain.
authors.forename: J Miguel
authors.initials: JM
authors.lastname: Rubí
authors.affiliation: Instituto de Física and Centro Internacional de Física da Matéria Condensada, Universidade de Brasília, Caixa Postal 04513, 70919-970 Brasília, Distrito Federal, Brazil.
authors.forename: Fernando A
authors.initials: FA
authors.lastname: Oliveira