Was Clarke a Voluntarist?

The distinction between voluntarism and intellectualism has recently been criticized for inaccurately characterizing early modern theories of divine freedom. In response, defenders of the distinction have argued that these labels are needed in order to account for the famous correspondence between Leibniz (intellectualist) and Clarke (voluntarist). In this paper, I argue that the voluntarism/intellectualism distinction is unable to account for the opposition between Leibniz and Clarke. In the first part, I provide an analysis of Clarke’s theory of divine freedom, and show how he employs the distinction between activity and passivity in order to account for the separation between God’s will and intellect, which ultimately safeguards God’s freedom. I also analyse Clarke’s correspondence with Leibniz, and show how Clarke deals with choice among equals, the principle of sufficient reason,and the principle of the best. In the second part, I argue on the basis of this analysis that Clarke is not a voluntarist, but should instead be interpreted as an intellectualist (if one wants to keep the labels). Therefore, the Leibniz-Clarke correspondence cannot be explained as a clash between voluntarism and intellectualism

Clarke's Rejection of Superadded Gravity in the Clarke-Collins Correspondence

In the past, experts have disagreed about whether Samuel Clarke accepted the idea that gravity is a power superadded to matter by God. Most scholars now agree that Clarke did not support superaddition. But the argumentation employed by Clarke to reject superaddition has not been studied before in detail. In this paper, I explicate Clarke's argumentation by relating it to an important discussion about the possibility of superadded gravity in the Clarke-Collins correspondence. I examine Clarke's responses to Collins and draw on his other works to reconstruct Clarke's reasons for rejecting superadded gravity

Of Clocks and Kings:Physics, Metaphysics, and the Role of God in Clarke’s Worldview

In this dissertation I examine how the English philosopher-theologian Samuel Clarke (1675--1729) attempted to reasonableness of Christianity and its compatibility with the new natural philosophy. In reaction to what he perceived as the problematic excesses of mechanical philosophy, with its looming threat of atheism, Clarke developed a series of arguments against atheism which aimed to show the shortcomings of a purely material or mechanical explanation of the universe, and demonstrate the overall `reasonability' of the Christian religion. Clarke aimed to demonstrate the `reasonableness' of Christianity by turning the `mathematical' style of reasoning of the mechanical philosophy against his atheist adversaries. Clarke's writings offer us a valuable case-study for the complex interplay of philosophy, science and religion in England at the start of the eighteenth century, and the impact of mechanical philosophy on natural theology. This dissertation aims to improve our understanding of Clarke's philosophy through careful examination of its principal components: The active role of God in the world, the perfection of God's plan, the existence of immaterial substances and powers, and the subsequent reasonability of the Christian religion. Taken together, the four chapters show Clarke's solutions to the atheist threats, and provide a coherent picture of Clarke's ideas about the nature of God and God's role in the world

Influence of X-ray Irradiation on the Properties of the Hamamatsu Silicon Photomultiplier S10362-11-050C

We have investigated the effects of X-ray irradiation to doses of 0, 200 Gy, 20 kGy, 2 MGy, and 20 MGy on the Hamamatsu silicon-photomultiplier (SiPM) S10362-11-050C. The SiPMs were irradiated without applied bias voltage. From current-voltage, capacitance/conductance-voltage, -frequency, pulse-shape, and pulse-area measurements, the SiPM characteristics below and above breakdown voltage were determined. Significant changes of some SiPM parameters are observed. Up to a dose of 20 kGy the performance of the SiPMs is hardly affected by X-ray radiation damage. For doses of 2 and 20 MGy the SiPMs operate with hardly any change in gain, but with a significant increase in dark-count rate and cross-talk probability.Comment: 21 pages,30 figure

Is variety the spice of life? An experimental investigation into the effects of species richness on self-reported mental well-being

Losses in biodiversity and trends toward urbanisation have reduced people's contact with biodiverse nature, yet the consequences for mental well-being are not well understood. Here, we demonstrate that greater plant and animal species richness in isolation causes an improvement in mental well-being. To do so, the present research experimentally manipulated species richness and assessed widely-used indicators of mental well-being. Participants viewed short videos of either high or low tree (Study 1) or bird (Study 2) species richness and reported on positive (i.e., vitality, positive affect) and negative (i.e., anxiety) indicators of mental wellbeing. Building on Study 1, Study 2 included an urban environment as a reference treatment and explored the role of giving participants information on the presented environment. We find that, in line with expectations, watching videos containing greater species richness consistently leads to higher mental well-being. We discuss findings in light of the importance of connecting people to biodiverse environments

Pattern formation during current sintering (Simulation)

Current sintering is becoming increasingly important for creating nanostructured materials from powders. Joule heating inside the sample enables the rapid densification necessary to preserve the nanostructure. However, the presence of electric fields and currents activates additional effects, such as inhomogeneous grain-growth and coarsening, thermoelectric effects, as well as dopant migration. In return, these effects influence the transport properties of the material during sintering which constitute feedback mechanisms that, ultimately, can lead to the formation of patterns. Please click Additional Files below to see the full abstract

Local DRLs and automated risk estimation in paediatric interventional cardiology

Introduction : Cardiac catheterization procedures result in high radiation doses and often multiple procedures are necessary for congenital heart disease patients. However, diagnostic reference levels (DRL) remain scarce. Our first goal was finding the optimal DRL parameter and determining appropriate DRLs. The second goal was to calculate organ doses (OD), effective doses (ED) and lifetime attributable risks (LAR) per procedure and to provide conversion factors based on dose area product (DAP). Materials and methods : DRLs are calculated for each procedure type, as the 75th percentile of the cumulative value per procedure from the corresponding parameter. All irradiation events in the DICOM Structured Reports were automatically processed and simulated using PCXMC, resulting in OD, ED and LAR. Using a Kruskal Wallis H test and subsequent pairwise comparisons, differences in median values of the DRL parameter between procedure types were assessed. Results : Linear regression showed a strong correlation and narrow confidence interval between DAP and product of body weight and fluoroscopy time (BWxFT), even when all procedures (diagnostic and interventional) are combined. Only 15% of the pairwise comparisons were statistically significant for DAP normalized to BWxFT (DAP(BWxFT)). The latter pairs contained less frequent procedure types with significant outliers. For DAP normalized to BW (DAP(BW)), 38% of the pairwise comparisons showed statistically significant differences. Conversion factors from DAP(BW) to OD and ED were reported for various weight groups, due to the higher correlation between DAP(BW) and both OD and ED than between DAP and both OD and ED. Conclusions : The P75 of DAP(BWxFT) for all procedures combined serves as an appropriate DRL value. This facilitates local DRL determination in smaller paediatric centres, which often have insufficient data to produce appropriate DRLs for different procedure types. Conversion factors are more reliable starting from DAP(BW) instead of DAP and should be used according to the appropriate BW group

Revealing the Competing Contributions of Charge Carriers, Excitons, and Defects to the Non-Equilibrium Optical Properties of ZnO

Due to its wide band gap and high carrier mobility, ZnO is an attractive material for light-harvesting and optoelectronic applications. Its functional efficiency, however, is strongly affected by defect-related in-gap states that open up extrinsic decay channels and modify relaxation timescales. As a consequence, almost every ZnO sample behaves differently, leading to irreproducible or even contradicting observations. Here, a complementary set of time-resolved spectroscopies is applied to two ZnO samples of different defect density to disentangle the competing contributions of charge carriers, excitons, and defects to the non-equilibrium dynamics after photoexcitation: Time-resolved photoluminescence, excited state transmission, and electronic sum frequency generation. Remarkably, defects affect the transient optical properties of ZnO across more than eight orders of magnitude in time, starting with photodepletion of normally occupied defect states on femtosecond timescales, followed by the competition of free exciton emission and exciton trapping at defect sites within picoseconds, photoluminescence of defect-bound and free excitons on nanosecond timescales, and deeply trapped holes with microsecond lifetimes. These findings do not only provide the first comprehensive picture of charge and exciton relaxation pathways in ZnO, but also uncover the microscopic origin of previous conflicting observations in this challenging material and thereby offer means of overcoming its difficulties