Commun. Comput. Phys., 2 (2007), pp. 358-366. Majority-Vote on Undirected Barabasi-Albert Networks F. W. S. Lima 1*1 Departamento de Fisica, Universidade Federal do Piaui, 57072-970 Teresina PI, Brazil. Received 23 July 2006; Accepted (in revised version) 9 August, 2006 Communicated by Dietrich Stauffer Available online 30 September 2006 doi:10.4208/cicp.2007.v2.p358 Abstract On Barab\'asi-Albert networks with $z$ neighbours selected by each added site, the Ising model was seen to show a spontaneous magnetisation. This spontaneous magnetisation was found below a critical temperature which increases logarithmically with system size. On these networks the majority-vote model with noise is now studied through Monte Carlo simulations. However, in this model, the order-disorder phase transition of the order parameter is well defined in this system and this was not found to increase logarithmically with system size. We calculate the value of the critical noise parameter $q_{c}$ for several values of connectivity $z$ of the undirected Barab\'asi-Albert network. The critical exponentes $\beta/\nu$, $\gamma/\nu$ and $1/\nu$ were also calculated for several values of $z$. Notice: Undefined variable: ams in /var/www/html/issue/abstract/readabs.php on line 163 PACS: 05.50+q, 68.35.Rh, 05.10.Ln Key words: Monte Carlo simulation, vote, networks, nonequilibrium. *Corresponding author. Email: wel@ufpi.br (F. W. S. Lima)