In this paper, a method is described that improves the perceived "smoothness" of motion depicted on rasterised Virtual Reality displays, by utilising the powerful information already contained in the virtual-world engine. Practical implementation of this method requires a slight realignment of one's view of the nature of a rasterised display, together with modest modifications to current image generation and rasterisation hardware. However, the resulting improvement in the quality of the perceived real-time image is obtained for only modest computational and hardware cost---offering the possibility of increasing the apparent graphical capabilities of existing technology by up to an order of magnitude. (25-Oct-92, 79 pages.) [Home page entry | DVI: 398 kB | PostScript: 589 kB].
In this short note, considerations for the implementation of motion extrapolation on a pixel-by-pixel basis are discussed. (14-Jan-93, 10 pages.) [Home page entry | DVI: 46 kB | PostScript: 98 kB].
I describe a simple kitchen-table construction that allows one to get a good feel for the human field of view. (20-Nov-95, 7 pages.) [Home page entry | DVI: 34 kB | PostScript: 76 kB].
The properties of specific and universal Fermat moduli are investigated, from both a numerical and a theoretical point of view. (3-Mar-92, 16 pages.) [Home page entry | DVI: 56 kB | PostScript: 129 kB].
We show that it is possible to obtain self-consistent and physically acceptable relativistic classical equations of motion for a point-like spin-half particle possessing an electric charge and a magnetic dipole moment, directly from a manifestly covariant Lagrangian, if the classical degrees of freedom are appropriately chosen. It is shown that the equations obtained encompass the well-tested Lorentz force and Thomas-Bargmann-Michel-Telegdi spin equations, as well as providing a definite specification of the classical magnetic dipole force, whose exact form has been the subject of recent debate. Radiation reaction---the force and torque on an accelerated particle due to its self-interaction---is neglected at this stage. (21-Sep-92, 12 pages.) [Home page entry | DVI: 50 kB | PostScript: 147 kB].
The Foldy-Wouthuysen transformation of the Dirac Hamiltonian is generally taught as simply a mathematical trick that allows one to obtain a two-component theory in the low-energy limit. It is not often emphasised that the transformed representation is the only one in which one can take a meaningful classical limit, in terms of particles and antiparticles. We briefly review the history and physics of this transformation. (31-Jan-95, 6 pages.) [Home page entry | DVI: 22 kB | PostScript: 94 kB].
In this short note, I point out that [p,q] does not equal (i h-bar), contrary to the original claims of Born and Jordan, and Dirac. Rather, [p,q] is equal to something that is infinitesimally different from (i h-bar). While this difference is usually harmless, it does provide the solution of the Born-Jordan "trace paradox" of [p,q]. More recently, subtleties of a very similar form have been found to be of fundamental importance in quantum field theory. (26-May-95, 6 pages.) [Home page entry | DVI: 22 kB | PostScript: 92 kB].
We show that, in valence quark models, the relativistic corrections to the SU(6) relation for the contribution of the electric dipole moments of the quarks to the electric dipole moment of the neutron can be expressed as a multiplicative correction factor. The correction factor is evaluated in light cone wavefunction models, in the bag model, and in relativistic mean-field models, and is found to lie between 1/3 and 1. We also show that, in these models, there is a linear relation between the correction to the SU(6) value for g_A and that for the electric dipole moment. (12-Jul-92, 8 pages.) [Home page entry | DVI: 20 kB | PostScript: 112 kB].
We show analytically that g_A goes to zero in the ultrarelativistic limit for the harmonic oscillator relativistic constituent quark model. (6-Feb-94, 5 pages.) [Home page entry | DVI: 15 kB | PostScript: 96 kB].
Copyright © 1994-1995 John P. Costella
(jpc@physics.unimelb.edu.au).
Accesses since 12 September 1995: