Propagation of Photons in Spacetime

A quantum field theory QED formalism is systematically developed to describe photon propagation in spacetime as a time evolution process based on the actual physical process of propagation between emitters and detectors as applied to the reflection of photons. This development, as well as early studies by Feynman, clearly show that a practical, computational and predictive dynamical formalism in spacetime was lacking. The present one generalizes to different experimental situations and other interacting field theories as well emphasizing the practicality of the problem treated here.     

Bonding a linearly piezoelectric patch on a linearly elastic body

A rigorous study of the asymptotic behavior of the system constituted by a very thin linearly piezoelectric plate bonded on a linearly elastic body supplies various models for an elastic body monitored by a piezoelectric patch.