Díaz Pernil, DanielPeña Cantillana, FranciscoGutiérrez Naranjo, Miguel Ángel2016-01-282016-01-282014978-84-940056-4-0http://hdl.handle.net/11441/33487It is well known that the polynomial complexity class of recognizer polarizationless P systems with active membranes, without dissolution and with division for elementary and non-elementary membranes is exactly the complexity class P (see [6], Th. 2). In this paper, we prove that if such P system model is endowed with antimatter and annihilation rules, then NP problems can be solved. In this way, antimatter is a frontier of tractability in Membrane Computing.application/pdfengAttribution-NonCommercial-NoDerivatives 4.0 InternacionalAttribution-NonCommercial-NoDerivatives 4.0 Internacionalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/conferenceObjectinfo:eu-repo/semantics/openAccess