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Gravitational lens is known for light bending, and gravitation can impact its frequency, but does it any impact on the polarity of this light?

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I really dislike giving one-sentence answers, but I can hardly stretch mine.

The polarization of light does not change because the Levi-Civita connection is torsion-free.

From your point of view, the light ray follows a curved path, and from the light's point of view, it follows a perfectly straight line¹. But neither you nor the ray will see any rotation of the tangent vector.

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¹ Okay, okay, light in a vacuum has no point of view, since it travels at the speed of light, but we can fix that by spraying some ideal interstellar medium in its path with the refraction index $n>1$ to derail it from the null geodesic and get its clock ticking, so it can observe what happens in space as time changes.

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