Photons contribute electromagnetic field that accompanies the gravitational field. These two fields may be, mutually, transformed through a kind of transformation matrix dependent upon the boundary conditions of the system. In this work trial would be made to find the nature of this transformation matrix considering a super system of photon in which both fields are unified.The unification of electromagnetic and gravitational fields leads to the concept of fundamental charge.
International Letters of Chemistry, Physics and Astronomy (Volume 12)
M. C. Das and R. Misra, "A Classical Approach of Unified Field", International Letters of Chemistry, Physics and Astronomy, Vol. 12, pp. 73-84, 2013