PolyP’s many faces

The many faces of superradiance

Inertial motion superradiance, the emission of radiation by an initially unexcited system moving inertially but superluminally through a medium, has long been known. Rotational superradiance, the amplification of radiation by a rotating rigid object, was recognized much later, principally in connection with black hole radiances. Here we review the principles of inertial motion superradiance and...

Predictive Coding: How Many Faces?

The Many Faces of Empathy

In 1872, Charles Darwin published The Expression of the Emotion in Man and Animals (1). In it, he sought to link certain movements, such as humans raising their eyebrows when surprised, to the concept of evolution and a link to common animal ancestry. Darwin’s impact on the psychology of the emotions continues to be felt to this day and his book is still considered a classic. One of the problem...

The Many Faces of Carbon

The Many Faces of Competition

Despite a great deal of theoretical research on competition, there has been limited empirical work assessing the type of competitive interaction that actually exists in the marketplace. The empirical work that has been conducted has suggested that there is significant variation in the type of competitive interaction across categories and across marketing instruments. Consequently, the central o...