Tendency to Maximum Complexity in a Non-Equilibrium Isolated System

The time evolution equations of a simplified isolated ideal gas, the "tetrahe- dral" gas, are derived. The dynamical behavior of the LMC complexity [R. Lopez-Ruiz, H. L. Mancini, and X. Calbet, Phys. Lett. A 209, 321 (1995)] is studied in this system. In general, it is shown that the complexity remains within the bounds of minimum and maximum complexity. We find that there are certain restrictions when the isolated "tetrahedral" gas evolves towards equilibrium. In addition to the well-known increase in entropy, the quantity called disequilibrium decreases monotonically with time. Furthermore, the trajectories of the system in phase space approach the maximum complexity.Comment: 22 pages, 0 figures. Published in Phys. Rev. E 63, 066116(9) (2001

Size Doesn't Matter: Towards a More Inclusive Philosophy of Biology

notes: As the primary author, O’Malley drafted the paper, and gathered and analysed data (scientific papers and talks). Conceptual analysis was conducted by both authors.publication-status: Publishedtypes: ArticlePhilosophers of biology, along with everyone else, generally perceive life to fall into two broad categories, the microbes and macrobes, and then pay most of their attention to the latter. ‘Macrobe’ is the word we propose for larger life forms, and we use it as part of an argument for microbial equality. We suggest that taking more notice of microbes – the dominant life form on the planet, both now and throughout evolutionary history – will transform some of the philosophy of biology’s standard ideas on ontology, evolution, taxonomy and biodiversity. We set out a number of recent developments in microbiology – including biofilm formation, chemotaxis, quorum sensing and gene transfer – that highlight microbial capacities for cooperation and communication and break down conventional thinking that microbes are solely or primarily single-celled organisms. These insights also bring new perspectives to the levels of selection debate, as well as to discussions of the evolution and nature of multicellularity, and to neo-Darwinian understandings of evolutionary mechanisms. We show how these revisions lead to further complications for microbial classification and the philosophies of systematics and biodiversity. Incorporating microbial insights into the philosophy of biology will challenge many of its assumptions, but also give greater scope and depth to its investigations

Disorder and complexity in and ideal on-equilibrium Fermi gas

A model of a non-equilibrium ideal Fermi gas has been devised which is simple enough to be treated analytically. Its properties are compared with a matching equilibrium gas and functions for “disorder” and “complexity” are defined and evaluated. The non-equilibrium entropy increases with “order” up to a certain particle number. Beyond this, the system reverts to the more usual behaviour of entropy increasing with “disorder”. But this tendency is only slight in this model

On a simple measure for complexity

A measure of “complexity” is proposed, based on appropriately defined notions of “order” and “disorder,” which has a considerable degree of flexibility in its dependence on these concepts. The possible functional dependencies which result encompass those of many earlier definitions of complexity. The proposed measure is in principle easy to calculate and has the property of an intensive thermodynamic quantity. With appropriate choices of parameters it behaves similarly to “effective measure complexity” for the logistic map. It is also a generalization of the “normalized complexity” of López-Ruiz et al., but does not suffer from “over-universality.

Ovarian Cysts and Ovarian Cancer

Ovarian cysts and tumours are a relatively common finding among women of many ages, particularly with the wider use of regular physical examinations and ultrasound. Most cysts and tumours in younger women are not malignant and can often be managed entirely within primary care. However, malignant tumours also occur. The average GP will see a new case of ovarian cancer every 4 to 5 years. Ovarian cancer is the second most common cancer of the female genital tract and the leading cause of death due to gynaecological malignancy. Ovarian cancer is frequently diagnosed at a late stage and carries a poor prognosis. Guidance published by the National Institute for Health and Clinical Excellence (NICE) in 2011 recognises this fact and recommends changes to the way in which cases are detected and managed in primary care. This article is a revision of a previous InnovAiT publication, incorporating recent changes to recommended practice

Reply to comments on "Simple measure of complexity"

We respond to the comment by Crutchfield, Feldman, and Shalizi [Comment in this issue, Phys. Rev. E 62, 2996 (2000)] and that by Binder and Perry [preceding Comment, Phys. Rev. E 62, 2998 (2000)], pointing out that there may be many maximum entropies, and therefore “disorders” and “simple complexities.” Which ones are appropriate depend on the questions being addressed. “Disorder” is not restricted to be the ratio of a nonequilibrium entropy to the corresponding equilibrium entropy; therefore, “simple complexity” need not vanish for all equilibrium systems, nor must it be nonvanishing for a nonequilibrium system