  We present the basic prerequisites of electromagnetism in flat spacetime and
provide the description of electromagnetism in terms of the Faraday tensor. We
generalise electromagnetic theory to a general relativistic setting,
introducing the Einstein field equations to describe the propagation of
electromagnetic radiation in curved space-time. We investigate gravitational
redshift and derive formulae for the combined effect of gravitational redshift
and the Doppler shift in curved spacetime.
