title: Carnot cycle for interacting particles in the absence of thermal noise.
abstract: A thermodynamic formalism is developed for a system of interacting particles under overdamped motion, which has been recently analyzed within the framework of nonextensive statistical mechanics. It amounts to expressing the interaction energy of the system in terms of a temperature θ, conjugated to a generalized entropy s(q), with q = 2. Since θ assumes much higher values than those of typical room temperatures T ≪ θ, the thermal noise can be neglected for this system (T/θ ≃ 0). This framework is now extended by the introduction of a work term δW which, together with the formerly defined heat contribution (δ Q = θ ds(q)), allows for the statement of a proper energy conservation law that is analogous to the first law of thermodynamics. These definitions lead to the derivation of an equation of state and to the characterization of s(q) adiabatic and θ isothermic transformations. On this basis, a Carnot cycle is constructed, whose efficiency is shown to be η = 1-(θ(2)/θ(1)), where θ(1) and θ(2) are the effective temperatures of the two isothermic transformations, with θ(1)>θ(2). The results for a generalized thermodynamic description of this system open the possibility for further physical consequences, like the realization of a thermal engine based on energy exchanges gauged by the temperature θ.
authors.affiliation: Centro Brasileiro de Pesquisas Físicas, Rua Xavier Sigaud 150 22290-180, Rio de Janeiro, Rio de Janeiro, Brazil and National Institute of Science and Technology for Complex Systems, Rua Xavier Sigaud 150 22290-180, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Evaldo M F
authors.initials: EM
authors.lastname: Curado
authors.affiliation: National Institute of Science and Technology for Complex Systems, Rua Xavier Sigaud 150 22290-180, Rio de Janeiro, Rio de Janeiro, Brazil and Departamento de Física, Universidade Federal de Sergipe, 49100-000, São Cristóvão, Sergipe, Brazil.
authors.forename: Andre M C
authors.initials: AM
authors.lastname: Souza
authors.affiliation: Centro Brasileiro de Pesquisas Físicas, Rua Xavier Sigaud 150 22290-180, Rio de Janeiro, Rio de Janeiro, Brazil and National Institute of Science and Technology for Complex Systems, Rua Xavier Sigaud 150 22290-180, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Fernando D
authors.initials: FD
authors.lastname: Nobre
authors.affiliation: National Institute of Science and Technology for Complex Systems, Rua Xavier Sigaud 150 22290-180, Rio de Janeiro, Rio de Janeiro, Brazil and Instituto de Física, Universidade Federal da Bahia 40210-340, Salvador, Bahia, Brazil.
authors.forename: Roberto F S
authors.initials: RF
authors.lastname: Andrade