We introduce an ACP-style discrete-time process algebra with relative timing, that features the empty process. Extensions to this algebra are described, and ample attention is paid to the considerations and problems that arise when introducing the empty process. We prove time determinacy, soundness, completeness, and the axioms of standard concurrency. 1991 Mathematics Subject Classification: 68Q10, 68Q22, 68Q55.
Jos C. M. Baeten, Jan A. Bergstra