## From reactions to observations: the directed bigraphical model

Università degli Studi di Udine

Thursday, 15 March 2007, 14:00

Cybernetica Bldg (Akadeemia tee 21), room B101

Slides from the talk [pdf]

**Abstract**: It is well-known that defining a labelled
transition system is very difficult. Traditionally, LTSs are crafted
"by hand", but the more complex is a calculus, the more difficult is
to devise its LTS. In the last years, much work has been spent in
looking for general procedures for deriving LTSs from reduction
systems (which are easier to state). In this respect, an emerging
meta-model are Milner's *bigraphs*, which allow to describe the
evolutions of systems with locations and connections. Remarkably,
these meta-models allow to derive a labelled transition system from a
reaction system via a general construction, called "relative
pullback". In this talk we will summarize the basic theory behind
relative pullbacks, and present directed bigraphs, a generalization of
original bigraphs, which allow to deal with more calculi than previous
models.

Tarmo Uustalu

Last update 21.3.2007