The bicomplex quantum Coulomb potential problem

Generalizations of the complex number system underlying the mathematical formulation of quantum mechanics have been known for some time, but the use of the commutative ring of bicomplex numbers for that purpose is relatively new. This paper provides an analytical solution of the quantum Coulomb potential problem formulated in terms of bicomplex numbers. We define the problem by introducing a bicomplex hamiltonian operator and extending the canonical commutation relations to the form [X_i,P_k] = i_1 hbar xi delta_{ik}, where xi is a bicomplex number. Following Pauli's algebraic method, we find the eigenvalues of the bicomplex hamiltonian. These eigenvalues are also obtained, along with appropriate eigenfunctions, by solving the extension of Schrodinger's time-independent differential equation. Examples of solutions are displayed. There is an orthonormal system of solutions that belongs to a bicomplex Hilbert space.Comment: Clarifications; some figures removed; version to appear in Can. J. Phy

Reactor power systems for manned earth orbital applications

Design requirements for reactor power system of manned earth orbital space statio

PARAMETERS OF BALL RELEASE IN WHEELCHAIR BASKETBALL FREE THROW SHOOTING

The purpose of this study was to identify the relationship between ball release parameters and player classification in wheelchair basketball free throw shooting. Utilizing three-dimensional (3D) video data collected during international competition, parameters of ball release associated with performance of the dean swish were examined. Significant differences were identified between the four player classes. The upper classes (3 & 4) tended to release the ball from a greater height, with less speed and a smaller angle of projection. The lower classes used a technique that demanded greater accuracy, but still managed to achieve free throw shooting percentages similar to the upper classes (3 & 4) who did not appear to utilize their height advantage

THE EFFECT OF WRIST RESTRAINTS ON WHEELING BIOMECHANICS

High intracarpal pressures created by hyperextension of the wrist during wheelchair propulsion is a suggested cause of median nerve dysfunction at the wrist/hand (Burnham & Steadward, 1994). An injury survey conducted by Burnham, Higgins & Steadward (1994) found that the wrist and hand were the most common sites of injury reported by wheelchair basketball players. The purpose of this study was to assess whether various forms of hand/wrist protection (visco-elastic padded glove, wrist splint, glove and splint) could effectively reduce the hyperextension seen at the wrist during wheelchair propulsion, thus potentially reducing the conditions predisposing to carpal tunnel syndrome. In addition, an evaluation of the various forms of hand/wrist protection and their effects on wheeling mechanics was also undertaken. The wheeling performances of thirteen subjects with prior wheeling experience were recorded using two SVHS videorecorders positioned to obtain a front and side view. Each subject propelled a standard wheelchair basketball chair mounted to a set of wheelchair rollers under four different conditions (no splint, visco-elastic padded glove on the palms, wrist splint, and glove and splint together). Under each of the conditions the subjects wheeled for thirty seconds both at their average speed and at their maximum speed. Reflective markers were placed on the joint centers of the shoulder and elbow, on the styloid processes of the radius and ulna, and on the distal ends of the 2nd and 5th metacarpals of the right limb to facilitate subsequent digitizing. Twelve points surrounding the activity space were filmed prior to testing and later utilized for calibration using the DLT method for three-dimensional coordinate data reconstruction, followed by smoothing of the data using a cubic spline. Three-dimensional joint angular displacement-time histories for the elbow and wrist were determined using the 3D coordinate data and the dot product identity. Data were analyzed using an one way AN OVA followed by Scheffe post hoc comparisons where appropriate. No differences were found to be significant between the conditions for the elbow angle, however significant differences were revealed for the wrist extension and wrist range of motion angles. Both splint conditions (splint, glove &splint) were significantly different from the non-restraint conditions (no splint, glove). The data suggest that the splints significantly reduced the amount of wrist extension as compared to the no restraint conditions. No significant differences were found between the conditions for maximum wheeling speed. Within the limitations of this study, it can be concluded that the wrist restraints significantly reduced wrist extension during wheeling and that the restraints did not significantly affect wheeling mechanics as suggested by the consistent elbow-angle time histories and wheeling speeds. REFERENCES Burnham, R & Steadward, R (1994). Upper extremity peripheral nerve entrapments among wheelchair athletes: prevalence, location, and risk factors. Archives of Physical Medicine and Rehabilitation, 75, 519 524. Burnham, R, Higgins, J. & Steadward, R. (1994). Wheelchair basketball injuries. Palaestra, 10(2), 43-49

Free fields via canonical transformations of matter-coupled 2D dilaton gravity models

It is shown that the 1+1-dimensional matter-coupled Jackiw-Teitelboim model and the model with an exponential potential can be converted by means of appropriate canonical transformations into a bosonic string theory propagating on a flat target space with an indefinite signature. This makes it possible to consistently quantize these models in the functional Schroedinger representation thus generalizing recent results on CGHS theory.Comment: 15 pages, Late

A triangulation study of young Women’s motivations for sending nudes to men

Women frequently send sexualized nude images to men (i.e., nudes), but women’s motivations for sending nudes are unclear because there are methodological limitations in the ways that cyber sexual activity has been defined and measured. To address these gaps in the literature, we employed a mixed method triangulation design to assess young women’s motivations for sending nudes to men, and how motivations compare when measured qualitatively and quantitatively. Across our qualitative and quantitative data, we found that women endorsed a plethora of motivations for sending nudes to men—far more than any one approach captured. The open-ended responses revealed positive sexual motives otherwise missing from the quantitative scales, which tended to overrepresent negative motivations. We also identified several critical discrepancies between endorsement of similar motivations in the qualitative versus quantitative responses, especially when it came to the idea of sending nudes for fun. Based on these findings, we suggest future researchers consider using more specific, and less stigmatizing language when assessing women’s motivations for sending nudes