The Whole Nine Yards: Should Student-Athletes Score an Education and Compensation?

This Article analyzes whether student-athletes are adequately compensated for their contributions. It also explores whether colleges and universities have any fiduciary duty to ensure a certain modicum of academic success and career development

Liberation of specific angular momentum through radiation and scattering in relativistic black-hole accretion discs

A key component of explaining the array of galaxies observed in the Universe is the feedback of active galactic nuclei, each powered by a massive black hole's accretion disc. For accretion to occur, angular momentum must be lost by that which is accreted. Electromagnetic radiation must offer some respite in this regard, the contribution for which is quantified in this paper, using solely general relativity, under the thin-disc regime. Herein, I calculate extremised situations where photons are entirely responsible for energy removal in the disc and then extend and relate this to the standard relativistic accretion disc outlined by Novikov & Thorne, which includes internal angular-momentum transport. While there is potential for the contribution of angular-momentum removal from photons to be >~1% out to ~10^4 Schwarzschild radii if the disc is irradiated and maximally liberated of angular momentum through inverse Compton scattering, it is more likely of order 10^2 Schwarzschild radii if thermal emission from the disc itself is stronger. The effect of radiation/scattering is stronger near the horizons of fast-spinning black holes, but, ultimately, other mechanisms must drive angular-momentum liberation/transport in accretion discs.Comment: 6 pages, 2 figures. Accepted for publication in PAS

Influence of diesel fuel on seed germination

The use of plant-based systems to remediate contaminated soils has become an area of intense scientific study in recent years and it is apparent that plants which grow well in contaminated soils need to be identified and screened for use in phytoremediation technologies. This study investigated the effect of diesel fuel on germination of selected plant species. Germination response varied greatly with plant species and was species specific, as members of the same plant family showed differential sensitivity to diesel fuel contamination. Differences were also seen within plant subspecies. At relatively low levels of diesel fuel contamination, delayed seed emergence and reduced percentage germination was observed for the majority of plant species investigated. Results suggest the volatile fraction of diesel fuel played an influential role in delaying seed emergence and reducing percentage germination. In addition, the remaining diesel fuel in the soil Lidded to this inhibitory effect on germination by physically impeding water and oxygen transfer between the seed and the surrounding soil environment, thus hindering the germination response

Mutual Dimension

We define the lower and upper mutual dimensions $mdim(x:y)$ and $Mdim(x:y)$ between any two points $x$ and $y$ in Euclidean space. Intuitively these are the lower and upper densities of the algorithmic information shared by $x$ and $y$. We show that these quantities satisfy the main desiderata for a satisfactory measure of mutual algorithmic information. Our main theorem, the data processing inequality for mutual dimension, says that, if $f:\mathbb{R}^m \rightarrow \mathbb{R}^n$ is computable and Lipschitz, then the inequalities $mdim(f(x):y) \leq mdim(x:y)$ and $Mdim(f(x):y) \leq Mdim(x:y)$ hold for all $x \in \mathbb{R}^m$ and $y \in \mathbb{R}^t$. We use this inequality and related inequalities that we prove in like fashion to establish conditions under which various classes of computable functions on Euclidean space preserve or otherwise transform mutual dimensions between points.Comment: This article is 29 pages and has been submitted to ACM Transactions on Computation Theory. A preliminary version of part of this material was reported at the 2013 Symposium on Theoretical Aspects of Computer Science in Kiel, German

Explaining Low Redshift Quasar Evolution

We have developed a flexible framework for constructing physical models of quasar evolution that can incorporate a wide variety of observational constraints, such as multi-wavelength quasar luminosity functions (QLFs), estimated masses and accretion rates of active black holes, space densities of quasar host galaxies, clustering measurements, and the mass function of black holes in the local universe. In this brief contribution we focus on the observed decline in the QLF break luminosity at $z<2$, which can be explained either by a shift toward lower characteristic accretion rates at low $z$ or by preferential suppression of activity in higher mass black holes.Comment: 2 pages, 1 figure, to be published in the Proceedings of "Multiwavelength AGN Surveys", Cozumel, Dec 8 - 12, 200