The C-metric as a colliding plane wave space-time

It is explicitly shown that part of the C-metric space-time inside the black hole horizon may be interpreted as the interaction region of two colliding plane waves with aligned linear polarization, provided the rotational coordinate is replaced by a linear one. This is a one-parameter generalization of the degenerate Ferrari-Ibanez solution in which the focussing singularity is a Cauchy horizon rather than a curvature singularity.Comment: 6 pages. To appear in Classical and Quantum Gravit

Adolescent Internet gambling: what do we actually know?

To date, little research has been done on the relationship between adolescent children and online gambling, especially regarding the conditions in which they can access e-gaming sites or the regularity with which they play. Professor Mark Griffiths, of Nottingham Trent University, examines how various studies, conducted in the EU and in the US, account for the links uniting adolescents and remote gaming

Adolescent gambling on the Internet: A review

Internet gambling is a relatively under-researched area. While our current knowledge remains in its infancy and the prevalence rates are relatively low, researchers and clinicians are predicting greater involvement among youth. A comprehensive search of the relevant literature was undertaken. The resulting relevant literature was classified into four areas. These were (a) the empirical studies on adolescent internet gambling, (b) online gambling-like experiences in adolescence, (c) adolescent gambling via social networking sites, and (d) adolescent gambling via online penny auction sites. Age verification in relation to prevention and regulation is also examined. It is concluded that young people appear to be very proficient in using and accessing new media and are likely to be increasingly exposed to remote gambling opportunities. These young people will therefore require education and guidance to enable them to cope with the challenges of convenience gambling in all its guises

Affect and the computer game player: the effect of gender, personality, and game reinforcement structure on affective responses to computer game-play

Previous research on computer games has tended to concentrate on their more negative effects (e.g., addiction, increased aggression). This study departs from the traditional clinical and social learning explanations for these behavioral phenomena and examines the effect of personality, in-game reinforcement characteristics, gender, and skill on the emotional state of the game-player. Results demonstrated that in-game reinforcement characteristics and skill significantly effect a number of affective measures (most notably excitement and frustration). The implications of the impact of game-play on affect are discussed with reference to the concepts of “addiction” and “aggression.

The psychology of music in gambling environments: an observational research note

Effects of the listening context on responses to music largely have been neglected despite the prevalence of music in our everyday lives. Furthermore, there has been no research on the role of music in gambling environments (e.g., casinos, amusement arcades) despite gambling's increased popularity as a leisure pursuit. An exploratory observational study in gambling arcades was carried out to investigate (i) how music is used as background music in amusement arcades, and (ii) how slot machines utilize music in their design. Results indicated that arcades often have music that caters for their customer demographics and that this may influence gambling behaviour. Furthermore, music from the slot machine itself appears to produce important impression formations about the machine (i.e., quality of the machine, familiarity, distinctiveness, and the sound of winning). It is suggested that music (whether it is in the gambling environment or in the activity itself) has the potential to be important in the acquisition, development, and maintenance of gambling behaviour. Some preliminary ideas and hypotheses to be tested are offered

Why do gamers buy 'virtual assets'? An insight in to the psychology behind purchase behaviour

The present study investigated the phenomenon of buying 'virtual assets' for game avatars. Virtual Assets are items that are bought with real-world money for an avatar in-game. Weapons, items, pets, mounts and skin customisations are the most popular examples. Using a qualitative methodology - in this case Interpretative phenomenological analysis (IPA) - six gamers that regularly bought in - game assets were interviewed. IPA was chosen because of its emphasis on lived experience, and each participant had subjective experiences of gaming and purchase behaviour. Of particular focus in this study were the superordinate themes of motivations for purchase behaviour, the resulting psychological impact on the gamer, the social benefits of gaming and virtual asset purchasing, emotional attachment, self-expression through the avatar, impulsivity versus thoughtfulness in purchase intention, and the impact of a transaction machinery on the 'game experience'. Motivations that were found to be of particular importance were item exclusivity, function, social appeal, and collectability. It was found that virtual items enable the gamer to express themselves, feel real satisfaction, and build lasting friendships. Essentially, virtual assets and gaming mostly had a very positive impact on the participant’s psychological wellbeing. Implications for gamers and games production companies are considered

Global aspects of accelerating and rotating black hole space-times

The complete family of exact solutions representing accelerating and rotating black holes with possible electromagnetic charges and a NUT parameter is known in terms of a modified Plebanski-Demianski metric. This demonstrates the singularity and horizon structure of the sources but not that the complete space-time describes two causally separated black holes. To demonstrate this property, the metric is first cast in the Weyl-Lewis-Papapetrou form. After extending this up to the acceleration horizon, it is then transformed to the boost-rotation-symmetric form in which the global properties of the solution are manifest. The physical interpretation of these solutions is thus clarified.Comment: 15 pages, 1 figure. To appear in Class. Quantum Gra

Accelerating Kerr-Newman black holes in (anti-)de Sitter space-time

A class of exact solutions of the Einstein-Maxwell equations is presented which describes an accelerating and rotating charged black hole in an asymptotically de Sitter or anti-de Sitter universe. The metric is presented in a new and convenient form in which the meaning of the parameters is clearly identified, and from which the physical properties of the solution can readily be interpreted.Comment: 5 pages. To appear in Phys. Rev.

Analysis of a Three Phase Induction Motor Directly from Maxwell's Equations

The torque developed in a three phase AC squirrel cage motor is usually expressed in terms of resistances and reactances of the stator, the rotor, and the motor as a whole. We use Maxwell's equations to find the torque in terms of geometrical parameters. This allows us to estimate the torque developed by a motor without knowing the details of its circuitry