If judged by their speed alone, photons are Newtonian particles. The speed of light VARIES, both in the presence and in the absence of gravity, just as does the speed of ordinary projectiles (e.g. bullets). Any relevant experiment (e.g. Michelson-Morley, Pound-Rebka, Doppler), if correctly interpreted, proves VARIABLE speed of light as per Newton's theory. Einsteinians usually teach the opposite but, curiously, tell the truth sometimes (the scientific community neither notices nor cares):

Albert Einstein Institute: "...you do not need general relativity to derive the correct prediction for the gravitational redshift. A combination of Newtonian gravity, a particle theory of light, and the weak equivalence principle (gravitating mass equals inertial mass) suffices. [...] The gravitational redshift was first measured on earth in 1960-65 by Pound, Rebka, and Snider at Harvard University..." http://www.einstein-online.info/spot...te_dwarfs.html

Yes, the Pound-Rebka experiment proved that the speed of light falling in gravity varies as per Newton's theory:

R. V. Pound and J. L. Snider, Effect of Gravity on Gamma Radiation: "It is not our purpose here to enter into the many-sided discussion of the relationship between the effect under study and general relativity or energy conservation. It is to be noted that no strictly relativistic concepts are involved and the description of the effect as an "apparent weight" of photons is suggestive. The velocity difference predicted is identical to that which a material object would acquire in free fall for a time equal to the time of flight." http://virgo.lal.in2p3.fr/NPAC/relat...iers/pound.pdf

"To see why a deflection of light would be expected, consider Figure 2-17, which shows a beam of light entering an accelerating compartment. Successive positions of the compartment are shown at equal time intervals. Because the compartment is accelerating, the distance it moves in each time interval increases with time. The path of the beam of light, as observed from inside the compartment, is therefore a parabola. But according to the equivalence principle, there is no way to distinguish between an accelerating compartment and one with uniform velocity in a uniform gravitational field. We conclude, therefore, that A BEAM OF LIGHT WILL ACCELERATE IN A GRAVITATIONAL FIELD AS DO OBJECTS WITH REST MASS. For example, near the surface of Earth light will fall with acceleration 9.8 m/s^2." http://web.pdx.edu/~pmoeck/books/Tipler_Llewellyn.pdf

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