The Eroding Artificial/Natural Distinction: Some Consequences for Ecology and Economics

Since Thomas Kuhn’s The Structure of Scientific Revolutions (1962), historians and philosophers of science have paid increasing attention to the implications of disciplinarity. In this chapter we consider restrictions posed to interdisciplinary exchange between ecology and economics that result from a particular kind of commitment to the ideal of disciplinary purity, that is, that each discipline is defined by an appropriate, unique set of objects, methods, theories, and aims. We argue that, when it comes to the objects of study in ecology and economics, ideas of disciplinary purity have been underwritten by the artificial-natural distinction. We then problematize this distinction, and thus disciplinary purity, both conceptually and empirically. Conceptually, the distinction is no longer tenable. Empirically, recent interdisciplinary research has shown the epistemological and policy-oriented benefits of dealing with models which explicitly link anthropogenic (i.e., “artificial”) and non-anthropogenic factors (i.e., “natural”). We conclude that, in the current age of the Anthropocene, it is to be expected that without interdisciplinary exchange, ecology and economics may relinquish global relevance because the distinct and separate systems to which each “pure” science was originally made to apply will only diminish over time

Implementing the three-particle quantization condition including higher partial waves

We present an implementation of the relativistic three-particle quantization condition including both $s$- and $d$-wave two-particle channels. For this, we develop a systematic expansion about threshold of the three-particle divergence-free K matrix, $\mathcal{K}_{\mathrm{df,3}}$, which is a generalization of the effective range expansion of the two-particle K matrix, $\mathcal{K}_2$. Relativistic invariance plays an important role in this expansion. We find that $d$-wave two-particle channels enter first at quadratic order. We explain how to implement the resulting multichannel quantization condition, and present several examples of its application. We derive the leading dependence of the threshold three-particle state on the two-particle $d$-wave scattering amplitude, and use this to test our implementation. We show how strong two-particle $d$-wave interactions can lead to significant effects on the finite-volume three-particle spectrum, including the possibility of a generalized three-particle Efimov-like bound state. We also explore the application to the $3\pi^+$ system, which is accessible to lattice QCD simulations, where we study the sensitivity of the spectrum to the components of $\mathcal{K}_{\mathrm{df,3}}$. Finally, we investigate the circumstances under which the quantization condition has unphysical solutions.Comment: 57 pages, 12 figures, 3 tables (v2: Made minor clarifications, updated a reference, fixed typos

A Point of Order

Paper by Stephen A. Tyle

Bound to Aim at Good Generally: A Sidgwickian Argument for Rational Impartialism

In this dissertation I defend an unorthodox theory of practical reason called Rational Impartialism. According to this view, one ought to have equal fundamental concern for the equal good of everyone. Central to my argument for Rational Impartialism are two of Henry Sidgwick’s axioms of ethics. According to the axiom of Equal Good, one ought to have equal fundamental concern for equal portions of the good. According to the axiom of Personal Irrelevance, the equal good of any two individuals is exactly similar qua portions of universal good. Sidgwick claims that from these two axioms we can deduce a principle of benevolence which is essentially the view I call Rational Impartialism. However, there are three problems with this deduction: (1) an egoist can accept the axioms but resist impartialism by insisting that ‘good’ is agent-relative, (2) if partiality towards loved ones is itself part of the good, then adherence to the axioms could be compatible with having ultimate reasons of partiality, (3) disagreement over the axiom of Equal Good seems to undermine its usefulness as a foundational ethical premise. I attempt to revive Sidgwick’s derivation of Rational Impartialism by responding to all three challenges

Entry-Level Cognitive Mathematics Skill and First-Semester Mathematics Performance as Correlates of Fall-to-Fall Retention of Community College Students

The purpose of this study was to investigate the relationship between first-semester mathematics performance and fall-to-fall retention for first-time-in-college, degree-seeking community college students. The study further refined the investigation by seeking to determine if the significance of this relationship was affected by student readiness for college-level mathematics as of the first semester of enrollment at the institution under study. The sample chosen for this study consisted of 1518 first-time-in-college, degree-seeking students enrolled in fall semester 2011 at a large, multi-campus community college in Virginia. The dependent variable was fall-to-fall retention, a commonly applied student success metric in the Virginia Community College System. The primary independent variable, first-semester mathematics performance, was tripartite, with each student having either enrolled in and successfully completed a first-semester mathematics course, enrolled in but failed to complete a first-semester mathematics course successfully, or deferred enrollment in mathematics until after the first semester. Quantitative statistical analysis was applied to determine the significance of the relationship between these variables within each of the subgroups and demographic constituencies. The study found that, regardless of readiness level, students who enrolled in and successfully completed a first-semester mathematics course experienced a fall-to-fall retention rate nearly 20% higher than that experienced by the sample taken as a whole. Meanwhile students who were unsuccessful in a first-semester mathematics class, as well as those who deferred enrollment in mathematics, experienced retention rates approximately I0% lower than that experienced by the sample overall. The study concluded that successful, first-semester enrollment in mathematics portends significantly higher fall-to-fall retention rates for degree-seeking students. However, disturbingly low success rates in both college-level and developmental-level mathematics courses suggest that first-semester enrollment in mathematics is a high-risk strategy for improving retention

SOUSA: the Swift Optical/Ultraviolet Supernova Archive

The Ultra-Violet Optical Telescope on the Swift spacecraft has observed hundreds of supernovae, covering all major types and most subtypes. Here we introduce the Swift Optical/Ultraviolet Supernova Archive (SOUSA), which will contain all of the supernova images and photometry. We describe the observation and reduction procedures and how they impact the final data. We show photometry from well-observed examples of most supernova classes, whose absolute magnitudes and colors may be used to infer supernova types in the absence of a spectrum. A full understanding of the variety within classes and a robust photometric separation of the groups requires a larger sample, which will be provided by the final archive. The data from the existing Swift supernovae are also useful for planning future observations with Swift as well as future UV observatories.Comment: Accepted for publication in the UV issue of Astrophysics and Space Science 10 pages, 6 figures SOUSA is an archive in progress with data being posted to the Swift SN website: http://swift.gsfc.nasa.gov/docs/swift/sne/swift_sn.htm

Three dimensional tracking with misalignment between display and control axes

Human operators confronted with misaligned display and control frames of reference performed three dimensional, pursuit tracking in virtual environment and virtual space simulations. Analysis of the components of the tracking errors in the perspective displays presenting virtual space showed that components of the error due to visual motor misalignment may be linearly separated from those associated with the mismatch between display and control coordinate systems. Tracking performance improved with several hours practice despite previous reports that such improvement did not take place

Influence of Season and Time of Day on Marsh Bird Detections

Call-broadcast surveys are frequently used to elicit responses of secretive marsh birds and produce greater detection rates than passive surveys. However, little is known about how detection rates of birds from these surveys differ by season and time of day. We conducted call-broadcast surveys for eight focal species at 56 wetlands throughout Iowa from 15 May–13 June 2010 (early season) and from 15 June–10 July 2010 (late season). Our focal species were Pied-billed Grebe (Podilymbus podiceps), American Bittern (Botaurus lentiginosus), Least Bittern (Ixobrychus exilis), King Rail (Rallus elegans), Virginia Rail (Rallus limicola), Sora (Porzana carolina), Common Gallinule (Gallinula chloropus), and American Coot (Fulica americana). Surveys were conducted in the early morning (30 mins before sunrise to 3 hrs after sunrise) and late evening (3 hrs before sunset to 30 mins after sunset) in accordance with the North American Marsh Bird Monitoring Protocol. We evaluated marsh bird detection rates as a function of a) time of day (morning and evening survey periods), b) season (early and late in the breeding season), and c) wetland size for four species with the greatest detection rates (Pied-billed Grebe, Least Bittern, Virginia Rail, and Sora). We also evaluated the above effects for two species groups; all eight species pooled and all rails pooled. We found significant (P \u3c 0.05) effects on the number of detections for Pied-billed Grebe in response to time of day, time of season, and wetland size; Sora, Virginia Rail, all rails, and all species had an effect of time of season only. Understanding seasonal and time-of-day differences in detection rates, as well as area dependence of secretive marsh birds, will refine existing monitoring protocols by allowing researchers to maximize detection probabilities of target species