Eckehard Schoell : Time-delayed feedback control - from nano to neuro
- Nonlinear and Complex Systems ( 203 Views )We review recent developments in the control of deterministic and stochastic nonlinear dynamics by time-delayed feedback methods [1]. We point out how to overcome the alleged odd number limitation for unstable periodic orbits, and discuss the control of complex chaotic or noise-induced space-time patterns. Our findings are applied to a selection of models ranging from semiconductor nanostructures, like resonant-tunneling diodes [2], to neural systems. [1] E. Sch{\"o}ll and H.G. Schuster (Eds.): Handbook of Chaos Control (Wiley-VCH, Weinheim, 2008), second completely revised and enlarged edition. [2] E. Sch{\"o}ll, Nonlinear spatio-temporal dynamics and chaos in semiconductors (Cambridge University Press, Cambridge, 2001).
Francesco Zamponi : Jamming and hard sphere glasses
- Nonlinear and Complex Systems ( 116 Views )I will review a theory of amorphous packings of hard spheres based on the assumption that these packings are the infinite pressure limit of long-lived metastable glassy states. Technically, the theory makes use of the replica method and of standard liquid theory; it gives predictions on both the structure and the thermodynamics of amorphous states. In dimensions between two and six these predictions can be successfully compared with numerical simulations. I will finally discuss the limit of large dimension, that is relevant for information theory problems, where an exact solution is possible. Ref: G.Parisi and F.Zamponi, J.Chem.Phys. 123, 144504 (2005); arXiv:0802.2180 (to appear on Rev.Mod.Phys.)