As fireflies with less light intensity move towards
high intensity fireflies which depends on attractiveness and light absorption.
The attractiveness is relative; it is seen in the eyes of the beholder or
judged by the other fireflies. Light intensity decreases with the distance from
its source, and it is also absorbed in the media, so we should allow the
attractiveness to vary with the degree of absorption. In the simplest form, the
light intensity I(r) varies according to the inverse square law I(r)
= Is/r2. For a given medium with a fixed γ, I between two fireflies f and h varies with rfh between them i.e.