Nominal techniques arise from studying structures which are very large, indeed potentially infinite, but exhibit so many symmetries that they can be concisely represented and manipulated; roughly speaking, they ``look the same from every angle’’. Structures of this kind abound in computer science, often arising from the use of atomic data items such as identifiers. For example, variable names in programming languages are drawn from a potentially infinite set, but it does not really matter what name a programmer chooses, and there is always a fresh name to choose.
Nominal sets, a mathematical theory suitable for studying names and other data atoms with their associated notions of freshness, binding, alpha-conversion and support, have attracted significant attention in Computer Science in the past 15 years. It has influenced research fields such as automata theory, concurrency theory, formal methods, and programming language design and semantics.
At FoPSS 2019 leading experts in the field will lecture on the current state of the art in nominal techniques. Loosely based on the books Nominal Sets: Names and Symmetry in Computer Science and Slightly Infinite Sets, the topics will vary from foundations of nominal sets, to applications of nominal techniques to several branches of Theoretical Computer Science, to tutorials on software tools that use nominal techniques.