Variational Monte Carlo study of core-valence separation schemes for first-row atoms and positive ions /

All-electron partitioning of wave functions into products ^core^vai of core and valence parts in orbital space results in the loss of core-valence antisymmetry, uncorrelation of motion of core and valence electrons, and core-valence overlap. These effects are studied with the variational Monte Carlo method using appropriately designed wave functions for the first-row atoms and positive ions. It is shown that the loss of antisymmetry with respect to interchange of core and valence electrons is a dominant effect which increases rapidly through the row, while the effect of core-valence uncorrelation is generally smaller. Orthogonality of the core and valence parts partially substitutes the exclusion principle and is absolutely necessary for meaningful calculations with partitioned wave functions. Core-valence overlap may lead to nonsensical values of the total energy. It has been found that even relatively crude core-valence partitioned wave functions generally can estimate ionization potentials with better accuracy than that of the traditional, non-partitioned ones, provided that they achieve maximum separation (independence) of core and valence shells accompanied by high internal flexibility of ^core and Wvai- Our best core-valence partitioned wave function of that kind estimates the IP's with an accuracy comparable to the most accurate theoretical determinations in the literature.

Tourism and the precautionary principle : a survey of academic and government stakeholders

The purpose of this exploratory investigation was to provide a more precise understanding and basis from which to assess the potential role of the precautionary principle in tourism. The precautionary principle, analogous to the ideal of sustainable development, is a future-focused planning and regulatory mechanism that emphasizes pro-action and recognizes the limitations of contemporary scientific methods. A total of 100 respondents (80 tourism academics, 20 regional government tourism officials) from Canada, United States, United Kingdom, Australia and New Zealand completed the webbased survey between May and June 2003. Respondents reported their understanding of the precautionary principle, rated stakeholder involvement and education strategies, assessed potential barriers in implementation, and appraised steps of a proposed fi-amework for implementation. Due to low sub sample numbers, measures of central tendency were primarily used to compare groups, while inferential statistics were applied when warranted. Results indicated that most respondents (79%) felt the principle could be a guiding principle for tourism, while local and regional government entities were reported to have the most power in the implementation process. Findings suggested close links between the precautionary principle and sustainability, as concern for future generations was the most critical element of the principle for tourism. Overall, tourism academics were more supportive of the precautionary principle in tourism than were regional government tourism officials. Only minor variation was found in responses among regional groups across all variables. This study established basic ground for understanding the precautionary principle in tourism and has been effective in formulating more precise questions for future research.

Histogram filtering as a tool in variational Monte Carlo optimization

Optimization of wave functions in quantum Monte Carlo is a difficult task because the statistical uncertainty inherent to the technique makes the absolute determination of the global minimum difficult. To optimize these wave functions we generate a large number of possible minima using many independently generated Monte Carlo ensembles and perform a conjugate gradient optimization. Then we construct histograms of the resulting nominally optimal parameter sets and "filter" them to identify which parameter sets "go together" to generate a local minimum. We follow with correlated-sampling verification runs to find the global minimum. We illustrate this technique for variance and variational energy optimization for a variety of wave functions for small systellls. For such optimized wave functions we calculate the variational energy and variance as well as various non-differential properties. The optimizations are either on par with or superior to determinations in the literature. Furthermore, we show that this technique is sufficiently robust that for molecules one may determine the optimal geometry at tIle same time as one optimizes the variational energy.

Variational Monte Carlo estimation of the dissociation energy of CuH using correlated sampling

A new approach to treating large Z systems by quantum Monte Carlo has been developed. It naturally leads to notion of the 'valence energy'. Possibilities of the new approach has been explored by optimizing the wave function for CuH and Cu and computing dissociation energy and dipole moment of CuH using variational Monte Carlo. The dissociation energy obtained is about 40% smaller than the experimental value; the method is comparable with SCF and simple pseudopotential calculations. The dipole moment differs from the best theoretical estimate by about 50% what is again comparable with other methods (Complete Active Space SCF and pseudopotential methods).

Can Mixed Martial Arts be Ethically Defended?: Autonomy, Paternalism and the Harm Principle

Abstract Mixed Martial Arts (MMA) and the Ultimate Fighting Championship (UFC) founded in 1993 have been under scrutiny for the past two decades. Unlike boxing, the ethical status of MMA and whether it is morally defensible have rarely been analyzed in the academic literature. I argue that MMA requires such an analysis because it is inherently violent. The purpose of this study was to examine elite-level MMA by referring to the ethical concepts of autonomy, paternalism and the Harm Principle. Findings from interviews with MMA athletes as well as my personal experience of MMA were presented to establish a deeper understanding of the sport and what it means to train and compete in a sport defined as violent. The conceptual analysis and findings of MMA athletes' experiences in this investigation resulted in the conclusion that MMA is ethically defensible. Additional findings, implications and recommendations for further research were also discussed.

Online Anonymity and the Kantian Publicity Principle: Can the Internet Solve the Paradox of Tyranny?

Immanuel Kant’s publicity maxim states that other-regarding actions are wrong if their maxim is not compatible with their being made public. This has the effect of forbidding dissent or rebellion against tyranny, since rebels cannot make their intentions and plans public. However, new internet technologies offer public speech from behind the “shield” of anonymity, allowing dissent to be public but preventing reprisals from tyrants. This thesis examines not only this possibility, but the value of internet-based discursive spaces for politics, their viability as a mode for political communication, and their implications for Classical and Enlightenment approaches to politics and intellectual virtue. Anonymous internet communications favour logos-based reasoning and discourse, which, in the liberal-democratic tradition, is preferable to phronesis and its attendant elitism and chauvinism. These technologies can open new vistas for liberal-democratic politics.