Editing Christopher Langton (section)

==Artificial life==

Langton made numerous contributions to the field of artificial life, both in terms of simulation and computational models of given problems and to philosophical issues. Early on, he identified the problems of information, computation and reproduction as intrinsically connected with complexity and its basic laws. Inspired by ideas coming from physics, particularly [[phase transition]]s, he developed several key concepts and quantitative measures for [[cellular automata]] and suggested that critical points separating order from disorder could play a very important role in shaping complex systems, particularly in biology. These ideas were also explored simultaneously, albeit with different approximations, by [[James P. Crutchfield]] and [[Per Bak]] among others.

While a graduate student at the [[University of Michigan]], Langton created the [[Langton's ant|Langton ant]] and [[Langton's loops|Langton loop]], both simple artificial life simulations, in addition to his lambda parameter, a dimensionless measure of complexity and computation potential in [[cellular automata]], given by a chosen state divided by all the possible states.<ref>{{Cite web|title=Introduction to the Edge of Chaos|url=http://godel.hws.edu/xJava/CA/EdgeOfChaos.html|access-date=2021-02-27|website=godel.hws.edu}}</ref> For a 2-state, 1-r neighborhood, 1D cellular automata the value is close to 0.5. For a 2-state, [[Moore neighborhood]], 2D cellular automata, like [[Conways Life|Conway's Life]], the value is 0.273.