: : One week ago, Pranov said:"There will be a redshift due : to the gravitational field, but the photon cannot lose : speed as it travels with the speed of light. As the : photon is redshifted it losses energy and the : gravitation upon it will therefore decrease,and if you : do the calculation it is seen that it can never lose : all its energy." : Does he mean light can escape from everything? Include : black holes?

Light can't escape from black holes, becasue the escape velocity is greater than the speed of light. (This is a somewhat simplistic answer - a full answer requires some study of general relativity.)