9 research outputs found
A Simple Cellular Automation that Solves the Density and Ordering Problems
Cellular automata (CA) are discrete, dynamical systems that perform computations
in a distributed fashion on a spatially extended grid. The dynamical behavior
of a CA may give rise to emergent computation, referring to the appearance of
global information processing capabilities that are not explicitly represented in the
system's elementary components nor in their local interconnections.1 As such, CAs
o?er an austere yet versatile model for studying natural phenomena, as well as a
powerful paradigm for attaining ?ne-grained, massively parallel computation.
An example of such emergent computation is to use a CA to determine the
global density of bits in an initial state con?guration. This problem, known as
density classi?cation, has been studied quite intensively over the past few years. In
this short communication we describe two previous versions of the problem along with their CA solutions, and then go on to show that there exists yet a third version
| which admits a simple solution
Parity Problem With A Cellular Automaton Solution
The parity of a bit string of length is a global quantity that can be
efficiently compute using a global counter in time. But is it
possible to find the parity using cellular automata with a set of local rule
tables without using any global counter? Here, we report a way to solve this
problem using a number of binary, uniform, parallel and deterministic
cellular automata applied in succession for a total of time.Comment: Revtex, 4 pages, final version accepted by Phys.Rev.
Probabilistic cellular automata with conserved quantities
We demonstrate that the concept of a conservation law can be naturally
extended from deterministic to probabilistic cellular automata (PCA) rules. The
local function for conservative PCA must satisfy conditions analogous to
conservation conditions for deterministic cellular automata. Conservation
condition for PCA can also be written in the form of a current conservation
law. For deterministic nearest-neighbour CA the current can be computed
exactly. Local structure approximation can partially predict the equilibrium
current for non-deterministic cases. For linear segments of the fundamental
diagram it actually produces exact results.Comment: 17 pages, 2 figure
Invariant Measures and Convergence for Cellular Automaton 184 and Related Processes
For a class of one-dimensional cellular automata, we review and complete the
characterization of the invariant measures (in particular, all invariant phase
separation measures), the rate of convergence to equilibrium, and the
derivation of the hydrodynamic limit. The most widely known representatives of
this class of automata are: Automaton 184 from the classification of S.
Wolfram, an annihilating particle system and a surface growth model.Comment: 18 page
On Fireflies, Cellular Systems, and Evolware
Many observers have marveled at the beauty of the synchronous flashing of fireflies that has an almost hypnotic effect. In this paper we consider the issue of evolving two-dimensional cellular automata as well as random boolean networks to solve the firefly synchronization task. The task was successfully solved by means of cellular programming based co-evolution performing computations in a completely local manner, each cell having access only to its immediate neighbor's states. An FPGA-based Evolware implementation on the BioWall's cellular tissue and different other simulations show that the approach is very efficient and easily implementable in hardware