Dirac Lecture 2 (of 4) - Quantum Electrodynamics

Can anyone help me with this question please? (UPDATE: Just Answered Aug 2014 - Big thanks to Brent Follin - PhD Student on Quora - who kindly persisted with me until I understood his answer. He supplied very Intuitive comments - Brent reminds me of this man filmed above!!!...) To solve the word’s energy crisis; find a star that’s emitted an infra-red photon. Just make sure the star you find is travelling sufficiently fast enough toward us so the photon is blue shifted into the gamma region far enough to have sufficient energy to last mankind for a millennium. It’s frequency appears to change depending on the relative velocity of the detector to the original source even though it’s detection may be millions of years later. Does this mean then that the photon has retained some information about it’s source? - it will always travel at speed C...