Unquenched Studies Using the Truncated Determinant Algorithm

A truncated determinant algorithm is used to study the physical effects of the quark eigenmodes associated with eigenvalues below 420 MeV. This initial high statistics study focuses on coarse ($6^4$) lattices (with O($a^2$) improved gauge action), light internal quark masses and large physical volumes. Three features of full QCD are examined: topological charge distributions, string breaking as observed in the static energy and the eta prime mass.Comment: Lattice2001(confinement); 3pgs(Latex), 4figs.(ps

Can Collimated Extraterrestrial Signals be Intercepted?

The Optical Search for Extraterrestrial Intelligence (OSETI) attempts to detect collimated, narrowband pulses of electromagnetic radiation. These pulses may either consist of signals intentionally directed at the Earth, or signals between two star systems with a vector that unintentionally intersects the Solar System, allowing Earth to intercept the communication. But should we expect to be able to intercept these unintentional signals? And what constraints can we place upon the frequency of intelligent civilisations if we do? We carry out Monte Carlo Realisation simulations of interstellar communications between civilisations in the Galactic Habitable Zone (GHZ) using collimated beams. We measure the frequency with which beams between two stars are intercepted by a third. The interception rate increases linearly with the fraction of communicating civilisations, and as the cube of the beam opening angle, which is somewhat stronger than theoretical expectations, which we argue is due to the geometry of the GHZ. We find that for an annular GHZ containing 10,000 civilisations, intersections are unlikely unless the beams are relatively uncollimated. These results indicate that optical SETI is more likely to find signals deliberately directed at the Earth than accidentally intercepting collimated communications. Equally, civilisations wishing to establish a network of communicating species may use weakly collimated beams to build up the network through interception, if they are willing to pay a cost penalty that is lower than that meted by fully isotropic beacons. Future SETI searches should consider the possibility that communicating civilisations will attempt to strike a balance between optimising costs and encouraging contact between civilisations, and look for weakly collimated pulses as well as narrow-beam pulses directed deliberately at the Earth.Comment: 12 pages, 7 figures, accepted for publication in JBI

Spatio-temporal Constraints on the Zoo Hypothesis, and the Breakdown of Total Hegemony

The Zoo Hypothesis posits that we have not detected extraterrestrial intelligences (ETIs) because they deliberately prevent us from detecting them. While a valid solution to Fermi's Paradox, it is not particularly amenable to rigorous scientific analysis, as it implicitly assumes a great deal about the sociological structure of a plurality of civilisations. Any attempt to assess its worth must begin with its most basic assumption - that ETIs share a uniformity of motive in shielding Earth from extraterrestrial contact. This motive is often presumed to be generated by the influence of the first civilisation to arrive in the Galaxy. I show that recent work on inter-arrival time analysis, while necessary, is insufficient to assess the validity of the Zoo Hypothesis (and its related variants). The finite speed of light prevents an early civilisation from exerting immediate cultural influence over a later civilisation if they are sufficiently distant. I show that if civilisation arrival times and spatial locations are completely uncorrelated, this strictly prevents the establishment of total hegemony throughout the Galaxy. I finish by presenting similar results derived from more realistic Monte Carlo Realisation simulations (where arrival time and spatial locations are partially correlated). These also show that total hegemony is typically broken, even when the total population of civilisations remains low. In the terminology of previous studies of solutions to Fermi's Paradox, this confirms the Zoo Hypothesis as a "soft" solution. However, an important question to be resolved by future work is the extent to which many separate hegemonies are established, and to what extent this affects the Zoo Hypothesis.Comment: 14 pages, 10 figures, accepted for publication in the International Journal of Astrobiolog

Current Developments in Services for People with Intellectual Disabilities

[Taken from Executive Summary] This literature review is the culmination of the Saskatchewan Community Living Division jurisdictional study which began in the autumn of 2003. Following a brief survey of developments in providing services to people with intellectual disabilities (hitherto the People) for creating the questionnaire for this study, information was gleaned from the provinces and territories on their services. The CLD Jurisdictional Project was completed in the spring of 2005. Subsequently, a thorough search and examination of pertinent resources for serving this People and for policy development was conducted. From over 800 documents about 350 were selected for this literature review. The material is recorded in the following chapters: Public Consultation and Policy Development; Social Philosophy: the philosophical influence on contemporary social issues; Definition of disabilities; Needs assessment systems; Human Rights; Advocacy; Community services & Deinstitutionalization; Issues and Influences; Citizenship; Inclusion; Self-determination; Person-centered planning; Supports; Respite; Individualized funding; Canadian governmental initiatives; Provincial Services

Physical Effects of Infrared Quark Eigenmodes in LQCD

A truncated determinant algorithm is used to study the physical effects of the quark eigenmodes associated with eigenvalues below 400 MeV. This initial study focuses on coarse lattices (with O(a^2) improved gauge action), light internal quark masses and large physical volumes. Four bellwether full QCD processes are discussed: topological charge distributions, the eta prime propagator, string breaking as observed in the static energy and the rho decay into two pions.Comment: LATTICE99(Confinement); 3pgs(Latex), 4figs.(eps

Radiation scales and the solar constant

Radiation measurement and solar constant determinatio