  The pathway model of Mathai (2005) mainly deals with the rectangular
matrix-variate case. In this paper the scalar version is shown to be associated
with a large number of probability models used in physics. Different families
of densities are listed here, which are all connected through the pathway
parameter 'alpha', generating a distributional pathway. The idea is to switch
from one functional form to another through this parameter and it is shown that
basically one can proceed from the generalized type-1 beta family to
generalized type-2 beta family to generalized gamma family when the real
variable is positive and a wider set of families when the variable can take
negative values also. For simplicity, only the real scalar case is discussed
here but corresponding families are available when the variable is in the
complex domain. A large number of densities used in physics are shown to be
special cases of or associated with the pathway model. It is also shown that
the pathway model is available by maximizing a generalized measure of entropy,
leading to an entropic pathway. Particular cases of the pathway model are shown
to cover Tsallis statistics (Tsallis, 1988) and the superstatistics introduced
by Beck and Cohen (2003).
