Schoonschip '91

The symbolic manipulation program Schoonschip is being made freely available for a number of computers with Motorola 680x0 cpu’s. It can run on machines with relatively modest memory and disk resources, and is designed to run as fast as possible given the host constraints. Memory and disk utilization can be adapted to tune performance. Recently added capabilities include a system for efficient generation of diagrams, gamma algebra for continuous dimensions, algorithmic improvements for handling large problems, and an increase in the allowed number of X expressions. 1. History The first working version of Schoonschip ran on an IBM 7094 in December, 1963. A basic problem in particle physics, namely, radiative corrections to photons interacting with a charged vector boson, was successfully completed. In 1966 Schoonschip was ported to the CDC 6600 series computers; and gradually, as hard disks and file storage became available, the distribution extended to encompass virtually all existing CDC machines. Even quite recently this version was used for a very complicated calculation of higher order effects in quantum chromodynamics in the USSR. Notable applications in quantum electrodynamics include works by Kinoshita and coauthors, [1] and Remiddi and coauthors, [2] among which we cite only a few. The early version of the Schoonschip manual by H. Strubbe [3] has been the standard reference for citations of Schoonschip itself. In 1983, when microprocessors of sufficient capability became available, Schoonschip was ported to a computer built around the Motorola 68000 microprocessor, the Charles River Data Systems machine. The operating system was UNIX-like, and the port to any other machine containing a 68000 series processor and featuring a UNIX-type operating system became trivial. 2. Features It is not likely that Schoonschip will ever have the popular constituency of programs like Maple and Mathematica. It does not have a graphics interface, and has much less built-in. ⋆ It can output formulas in Fortran format, but not in TeX or PostScript format. Although there is no reason why it cannot be used for general purposes, with a few exceptions its primary role so far has been that of a scientific instrument (especially in particle physics); and it demands a certain level of mathematical expertise for its effective use. In this section, we review some of the features that are special to Schoonschip, or relatively new to it. ⋆ There does exist the beginning of a mathematics and particle physics knowledge base of Schoonschip procedures, some of which is provided in the current distribution.