There is no refractive index, because it is not refraction, as you have been told several times.

There is no refractive index, because it is not refraction, as you have been told several times.

Does variable deflective index exist there?

What is a variable deflective index?

What is a variable deflective index?

Can we define deflection angle on short part of photon path in gravitational field?

Can we define deflection angle on short part of photon path in gravitational field?

 

See post #6.

 

See post #6.

I think deflection angle of photon approaching(under some angle) to mass on short part of the photon path = r_s/r₂ - r_s/r₁

_{Can we define the travel time of photon on the part of photon path in seconds of far observer?}