On the necessity of complexity

Wolfram's Principle of Computational Equivalence (PCE) implies that universal complexity abounds in nature. This paper comprises three sections. In the first section we consider the question why there are so many universal phenomena around. So, in a sense, we week a driving force behind the PCE if any. We postulate a principle GNS that we call the Generalized Natural Selection Principle that together with the Church-Turing Thesis is seen to be equivalent to a weak version of PCE. In the second section we ask the question why we do not observe any phenomena that are complex but not-universal. We choose a cognitive setting to embark on this question and make some analogies with formal logic. In the third and final section we report on a case study where we see rich structures arise everywhere.Comment: 17 pages, 3 figure

Minimal tau approximation and simulations of the alpha effect

The validity of a closure called the minimal tau approximation (MTA), is tested in the context of dynamo theory, wherein triple correlations are assumed to provide relaxation of the turbulent electromotive force. Under MTA, the alpha effect in mean field dynamo theory becomes proportional to a relaxation time scale multiplied by the difference between kinetic and current helicities. It is shown that the value of the relaxation time is positive and, in units of the turnover time at the forcing wavenumber, it is of the order of unity. It is quenched by the magnetic field -- roughly independently of the magnetic Reynolds number. However, this independence becomes uncertain at large magnetic Reynolds number. Kinetic and current helicities are shown to be dominated by large scale properties of the flow.Comment: 11 pages, 12 figures, accepted by A&

Framings of nature in Planet Earth II and Wild Safari LIVE

The percentage of the world’s population living in cities continues to grow, while media technologies become ever more ubiquitous. As a result, the mass media’s role in connecting the general public to the natural world will only increase; the wildlife genre of television may have a particularly large role to play in this regard. Unfortunately, previous authors have argued that the over-dramatized depictions of nature in mainstream wildlife programs may serve to disconnect viewers from the natural world. Scholarship has also not kept up with recent developments in wildlife television, with few authors writing about hugely successful programs like Planet Earth II or innovative series such as Wild SafariLIVE. To understand how each of these programs portrays the natural world, FRAMINGS OF NATURE IN PLANET EARTH II AND WILD SAFARILIVE by Josh Gross used a three-stage model from visual anthropology to apply the most widely-cited definition of media frames to their content: identifying repeating patterns of messages, or frames, within a sample of episodes. I then drew on literature about universal human values and connectedness to nature to theorize about how the most common frames in each program, along with more general features, might influence viewers’ pro-environmental attitudes and behaviors. I found that the dominant messaging pattern in Planet Earth II is “Spectacle,” whereas Wild SafariLIVE emphasizes “Discovery and Exploration.” While both of these programs are likely to foster pro-environmental attitudes and behaviors, Wild SafariLIVE might do so more effectively

Spartan Daily, October 6, 2005

Volume 125, Issue 24https://scholarworks.sjsu.edu/spartandaily/10167/thumbnail.jp