When an observer gazes directly at a rigid spherical object moving at constant speed along a line directed at the head, both monocular and binocular retinal image correlates of time to collision (TTC) are available provided that the object is not too small. The monocular correlate is not available for very small objects and is invalid for rotating aspherical objects, while the binocular correla...

The recorded music industry is essentially a creation of the 20th century, starting soon after the invention of the first recorded sounds. Computer technology and the seemingly free distribution of music through so-called “peer-to-peer” systems such as Napster and its descendents threaten to destroy this industry, or at the very least, disrupt its current revenue model. Proponents of computer f...