Global and local aspects of spectral actions

Global Aspects of Ergodic Group Actions

The study of dynamical systems has its origins in the classical mechanics of Newton and his successors. That theory concerns the behavior of solutions of certain differential equations on manifolds. The modern theory has flourished in many directions that are best described by focusing on different features of the classical systems. For example, keeping only the topological structure led to the...

Global Aspects of Ergodic Group Actions and Equivalence Relations

Gorenstein global dimensions for Hopf algebra actions

Let $H$ be a Hopf algebra and $A$ an $H$-bimodule algebra‎. ‎In this paper‎, ‎we investigate Gorenstein global dimensions for Hopf‎ ‎algebras and twisted smash product algebras $Astar H$‎. ‎Results from‎ ‎the literature are generalized‎. 

From Local Actions to Global Tasks: Stigmergy and Collective Robotics

This paper presents a series of experiments where a group of mobile robots gather 81 randomly distributed objects and cluster them into one pile. Coordination of the agents’ movements is achieved through stigmergy. This principle, originally developed for the description of termite building behaviour, allows indirect communication between agents through sensing and modification of the local env...

Integrating global and local aspects of visual occlusion.

The phenomenon of visual occlusion has frequently been studied by means of two-dimensional line drawings. These drawings may elicit various interpretations. Sometimes a mosaic of shapes is seen, sometimes a shape that partly occludes another shape. In the latter case, observers often have a clear idea about the form of the partly occluded shape. Local and global pattern aspects both seem to be ...