A photon's point of view is not an inertial frame of reference. That is one of the
big concepts of Special Relativity. Refractive index is caused by absorption and re-emission of photons. Look at the relationship between refractive index and dielectric constant, then the (never observed) Scharnhorst effect,
http://arXiv.org/abs/gr-qc/0107091 http://arXiv.org/abs/quant-ph/0010055 Phys. Lett. B236 354 (1990)
Phys. Lett. B250 133 (1990)
J Phys A26 2037 (1993)
Light travels at lightspeed regardless of the medium. The frequency is not altered by refractive index, only the wavelength.
I thought that the reason photons often seem to decide where they are retroactivly
Don't anthropomorphize. Look up quantum eraser and quantum double eraser experiments.
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"quantum eraser" double 593 hits
Remember what Feynman said about quantum mechanics, "shut up and calculate."