The Reaction Systems Webpage

• October 2025. Open for submissions: special issue of Natural Computing on "Theory and applications of reaction systems". Editors: Paolo Bottoni, Maciej Koutny, Ion Petre. 

• September 2025. Reaction Systems workshop: program available online at https://www.reactionsystems.org/reaction-systems-workshop-2025. The abstracts of the talks are avilable there as well. 

• March 2025. Reaction systems workshop: the 5th editionto take place in Nice, France, September 2, 2025. Details at https://www.reactionsystems.org/reaction-systems-workshop-2025.

• September 2024. Open for submissions: special issue of Natural Computing on reaction systems to be published in late 2025 - early 2026. Editors: Linda Brodo, Roberta Gori, Paolo Milazzo, Ion Petre. 

• September 2024. Reaction systems workshop: the 4th edition takes place in Pisa, Italy. Program available at https://biomedinfo.di.unipi.it/cmsb2024/detailed_program/2024-09-18.html. 

• September 2024. The email list for reaction systems available for subscription at https://www.reactionsystems.org/home. 

• September 2024. The reaction systems website launched

• June 2024. Published: special collection of Natural Computing on Reaction Systems available at https://link.springer.com/collections/efgbgebabf. 

A reaction system is a model of computation introduced by Andrzej Ehrenfeucht and Grzegorz Rozenberg, inspired by the functioning of the living cell and, in particular, by the interactions between biochemical reactions in the living cell. Since their introduction almost 20 years ago, the topic of reaction systems matured into a broad research area, guided by both biological motivations, as well as by the need to understand the concept of interactive computations. 

The key concept in this model is that the interactions are based on the mechanisms of facilitation and inhibition: the result of a reaction may facilitate some reactions (by producing their reactants) and it may inhibit some reactions (by producing their inhibitors). 

A series of workshops and schools on reaction systems was initiated, driven by the growing interest in reaction systems research. The goal of this workshop series is to provide a forum for exchanging research ideas, for initiating new collaborations, and for strengthening existing collaborations. 

• Fifth edition: Nice, France, September 2, 2025. 

• Fourth edition: Pisa, Italy, September 2024.

• Third edition: Jacksonville, Florida, USA, March 2023. 

• Second edition: Torun, Poland, June 2019. 

• First edition: Milano, Italy, June 2018. 

• Linda Brodo, Roberta Gori, Paolo Milazzo, Ion Petre. Natural Computing, special issue on “Reaction Systems”, 2025, in progress.

• Daniela Genova, Ion Petre. Natural Computing, special issue on “Reaction Systems”, vol. 23, issue 2, 2024.https://doi.org/10.1007/s11047-024-09991-4.  

• Lukasz Mikulski, Ion Petre. Special issue on Reaction Systems, Theoretical Computer Science, vol. 881, 1-15, 2021. https://www.sciencedirect.com/journal/theoretical-computer-science/vol/881/suppl/C

• Lukasz Mikulski, Ion Petre. Special issue on Reaction Systems, Journal of Membrane Computing, vol. 2, 2020. https://doi.org/10.1007/s41965-020-00047-x

A doctoral course on reaction systems was initiated by Grzegorz Rozenberg at University of Siena, Italy since 2014, hosted by Moreno Falaschi. Starting in 2024 the course was lectured by Ion Petre.