An ADM 3+1 formulation for Smooth Lattice General Relativity

A new hybrid scheme for numerical relativity will be presented. The scheme will employ a 3-dimensional spacelike lattice to record the 3-metric while using the standard 3+1 ADM equations to evolve the lattice. Each time step will involve three basic steps. First, the coordinate quantities such as the Riemann and extrinsic curvatures are extracted from the lattice. Second, the 3+1 ADM equations are used to evolve the coordinate data, and finally, the coordinate data is used to update the scalar data on the lattice (such as the leg lengths). The scheme will be presented only for the case of vacuum spacetime though there is no reason why it could not be extended to non-vacuum spacetimes. The scheme allows any choice for the lapse function and shift vectors. An example for the Kasner $T^3$ cosmology will be presented and it will be shown that the method has, for this simple example, zero discretisation error.Comment: 18 pages, plain TeX, 5 epsf figues, gzipped ps file also available at http://newton.maths.monash.edu.au:8000/preprints/3+1-slgr.ps.g

Differences in use and function of verbal irony between real and fictional discourse: (mis)interpretation and irony blindness

This paper presents a contrastive approach to the presence of two distinct types of verbal irony in real (natural, unscripted) versus fictional (scripted) discourse, with a special focus on irony blindness, i.e. the inability to recognize ironic utterances. Irony strategies are categorized into two general types, based on the relationship between the expressed and the intended meaning (Type 1: meaning reversal and Type 2: meaning replacement). First, the differences between these two types are discussed in terms of use, interpretation, and misinterpretation. It is found that the first type of irony strongly prevails in natural discourse, while the second type is considerably more present in fictional discourse than it is in natural discourse. At the same time, the first type of irony appears to be more at risk of misinterpretation in natural discourse, as opposed to the second type, which seems to be a safer (even though less frequently selected) option. These findings are then further analyzed in light of the discussion concerning fictional (comedic, in particular) irony blindness and the construction and role of the irony blind characters. Interestingly, the causes of fictional irony blindness are found to correlate more strongly with the (more humorous) misinterpretation of the second type of irony

Individual differences and health in chronic pain: are sex-differences relevant?

Background: Because psychological variables are known to intercorrelate, the goal of this investigation was to compare the unique association between several well-established psychological constructs in pain research and pain-related outcomes. Sex differences are considered because pain is experienced differently across sex groups. Methods: Participants were 456 consecutive chronic pain patients attending a tertiary pain clinic (mean age = 58.4 years, SD = 14.8, 63.6% women). The study design was cross-sectional. Psychological constructs included personality (NEO-Five Factor Inventory), irrational thinking (General Attitudes and Beliefs Scale), and coping (Social Problem Solving Inventory). Outcomes were pain severity and interference (Brief Pain Inventory) and physical, general, and mental health status (Short Form-36). To decide whether the bivariate analyses and the two-block, multivariate linear regressions for each study outcome (block 1 = age, sex, and pain severity; block 2 = psychological variables) should be conducted with the whole sample or split by sex, we first explored whether sex moderated the relationship between psychological variables and outcomes. An alpha level of 0.001 was set to reduce the risk of type I errors due to multiple comparisons. Results: The moderation analyses indicated no sex differences in the association between psychological variables and study outcomes (all interaction terms p > .05). Thus, further analyses were calculated with the whole sample. Specifically, the bivariate analyses revealed that psychological constructs were intercorrelated in the expected direction and mostly correlated with mental health and overall perceived health status. In the regressions, when controlling for age, sex, and pain severity, psychological factors as a block significantly increased the explained variance of physical functioning (ΔR2 = .037, p < .001), general health (ΔR2 = .138, p < .001), and mental health (ΔR2 = .362, p < .001). However, unique associations were only obtained for mental health and neuroticism (β = − 0.30, p < .001) and a negative problem orientation (β = − 0.26, p < .001). Conclusions: There is redundancy in the relationship between psychological variables and pain-related outcomes and the strength of this association is highest for mental health status. The association between psychological characteristics and health outcomes was comparable for men and women, which suggests that the same therapeutic targets could be selected in psychological interventions of pain patients irrespective of sex

Resolving Parent-Child Differences

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Productivity Differences

Many technologies used by the LDCs are developed in the OECD economies, and as such, are used to make optimal use of the skills of these richer countries' workforces. Due to differences in the supply of skills, some of tasks performed by skilled workers in the OECD economies will be carried out by unskilled workers in the LDCs. Since the technologies in these tasks are designed to be used by skilled workers, productivity in the LDCs will be low. Even when all countries have equal access to new technologies, this mismatch between skills and technology can lead to sizeable differences in total factor productivity and output per worker. Our theory also suggests that productivity differences should be highest in medium-tech sectors, and that the trade regime and the degree of intellectual property right enforcement in the LDCs have an important effect on the direction of technical change and on productivity differences.Development; Directed Technical Change; Intellectual Property Rights; Skills; Technology; Total Factor Productivity