5 research outputs found
Additive one-dimensional cellular automata are chaotic according to Devaney's definition of chaos
AbstractWe study the chaotic behavior of a particular class of dynamical systems: cellular automata. We specialize the definition of chaos given by Devaney for general dynamical systems to the case of cellular automata. A dynamical system (X,F) is chaotic according to Devaney's definition of chaos if its transition map F is sensitive to the initial conditions, topologically transitive, and has dense periodic orbits on X. Our main result is the proof that all the additive one-dimensional cellular automata defined on a finite alphabet of prime cardinality are chaotic in the sense of Devaney
Mind out of matter: topics in the physical foundations of consciousness and cognition
This dissertation begins with an exploration of a brand of dual
aspect monism and some problems deriving from the distinction between
a first person and third person point of view. I continue with an outline
of one way in which the conscious experience of the subject might arise
from organisational properties of a material substrate. With this picture to
hand, I first examine theoretical features at the level of brain organisation
which may be required to support conscious experience and then discuss
what bearing some actual attributes of biological brains might have on
such experience. I conclude the first half of the dissertation with
comments on information processing and with artificial neural networks
meant to display simple varieties of the organisational features initially
described abstractly.While the first half begins with a view of conscious experience and
infers downwards in the organisational hierarchy to explore neural
features suggested by the view, attention in the second half shifts towards
analysing low level dynamical features of material substrates and inferring
upwards to possible effects on experience. There is particular emphasis on
clarifying the role of chaotic dynamics, and I discuss relationships between
levels of description of a cognitive system and comment on issues of
complexity, computability, and predictability before returning to the topic
of representation which earlier played a central part in isolating features of
brain organisation which may underlie conscious experience.Some themes run throughout the dissertation, including an
emphasis on understanding experience from both the first person and the
third person points of view and on analysing the latter at different levels
of description. Other themes include a sustained effort to integrate the
picture offered here with existing empirical data and to situate current
problems in the philosophy of mind within the new framework, as well as
an appeal to tools from mathematics, computer science, and cognitive
science to complement the more standard philosophical repertoire
MS FT-2-2 7 Orthogonal polynomials and quadrature: Theory, computation, and applications
Quadrature rules find many applications in science and engineering. Their analysis is a classical area of applied mathematics and continues to attract considerable attention. This seminar brings together speakers with expertise in a large variety of quadrature rules. It is the aim of the seminar to provide an overview of recent developments in the analysis of quadrature rules. The computation of error estimates and novel applications also are described
Generalized averaged Gaussian quadrature and applications
A simple numerical method for constructing the optimal generalized averaged Gaussian quadrature formulas will be presented. These formulas exist in many cases in which real positive GaussKronrod formulas do not exist, and can be used as an adequate alternative in order to estimate the error of a Gaussian rule. We also investigate the conditions under which the optimal averaged Gaussian quadrature formulas and their truncated variants are internal