Ultraviolet divergence short distances. The name comes from the earliest example of such a divergence, the "ultraviolet catastrophe" first encountered in understanding blackbody radiation. According to classical physics at the end of the nineteenth century, the quantity of radiation in the form of light released at any specific wavelength should increase with decreasing wavelength—in particular, there should be considerably more ultraviolet light released from a blackbody radiator than infrared light. Measurements showed the opposite, with maximal energy released at intermediate wavelengths, suggesting a failure of classical mechanics. This problem eventually led to the development of quantum mechanics. The successful resolution of the
Ultraviolet communication in butterflies communicate their receptivity to males using their ultraviolet communication system. The ultraviolet reflection is thought to be concentrated to the ventral side of a female’s hind wing. Yoshiaki Obara determined this experimentally by comparing the number of approaches to different parts of butterfly wings. The results showed that the female’s ventral hind wing was the greatest releaser of male sexual behavior. Although ultraviolet reflectance releases the sexual behavior, the strongest reflection of UV light is not the strongest releaser for the behavior. As a result, male white cabbage butterflies must have a preference for a certain level of UV reflectance