Original sentence: In computer science the, the Actor model and  process calculi are two closely related approaches to the modelling of concurrent digital computation.There are many similarities between the two approaches, but also several differences (some philosophical, some technical):.There is only one Actor model; there are numerous process calculi (including CSP, CCS, and the π-calculus).physical laws; the process calculi were inspired by algebra
Edited sentence: (See Prospects for the Actor model.In computer science the Actor model is related to  process calculi models of concurrent digital computation.The Actor model differs from the process calculi in several ways:.The Actor model is closely related to the engineering concurency requirements of many-core (Platform 2015 Unveiled at IDF Spring 2005) computer architectures and Web Services.There is no global state in modeling computational steps in the Actor model (see Actor model theory, fairness and Actor model early history).There is only one Actor model whereas there are numerous process calculi.physical laws   (see Actor model early history), whereas the process calculi were inspired by algebra