Lab Home | Phone | Search
Center for Nonlinear Studies  Center for Nonlinear Studies
 Home 
 People 
 Current 
 Affiliates 
 Alumni 
 Visitors 
 Students 
 Research 
 ICAM-LANL 
 Quantum 
 Publications 
 Publications 
 2007 
 2006 
 2005 
 2004 
 2003 
 2002 
 2001 
 2000 
 <1999 
 Conferences 
 Workshops 
 Sponsorship 
 Talks 
 Colloquia 
 Colloquia Archive 
 Seminars 
 Postdoc Seminars Archive 
 Quantum Lunch 
 CMS Colloquia 
 Q-Mat Seminars 
 Q-Mat Seminars Archive 
 Archive 
 Kac Lectures 
 Dist. Quant. Lecture 
 Ulam Scholar 
 Colloquia 
 
 Jobs 
 Students 
 Summer Research 
 Student Application 
 Visitors 
 Description 
 Past Visitors 
 Services 
 General 
 PD Travel Request 
 
 History of CNLS 
 
 Maps, Directions 
 CNLS Office 
 T-Division 
 LANL 
 
Monday, November 17, 2014
3:00 PM - 4:00 PM
CNLS Conference Room (TA-3, Bldg 1690)

Colloquium

What Do Sudoku and Turbulence Have in Common?

Zoltan Toroczkai
University of Notre Dame

The mathematical structure of many number puzzles such as Sudoku is akin to hard constraint satisfaction problems lying at the basis of applications that include protein folding and the ground-state problem of glassy spin systems. We introduce an exact mapping of Sudoku into a deterministic, continuous-time (analog) dynamical system which solves any puzzle without backtracking or random restarts. (All previous algorithms use backtracking.) We also show that the difficulty of Sudoku translates into transient turbulent behavior exhibited by this dynamical system, and that the escape rate, an invariant of transient turbulent flows, provides a scalar measure of the puzzle’s difficulty that correlates well with human difficulty ratings and it can be used to define a "Richter-type" scale of puzzle hardness. Sudoku is only used as an example, the analog method presented here is applicable to all hard decision type problems (NP-complete problems) with applications both in fundamental sciences (physics, biology) and in industry (e.g., scheduling, public-key cryptography, chip design, etc).

Host: Aric Hagberg