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> On a small scale, planar waves can be modeled like flat sheets of paper traveling through space without any angular momentum (no twisting motion).

They certainly have angular momentum, it just depends on the choice of origin. If you pick an origin along the peak ray of the plane wave, there will be no twist around that point. Just like with a particle traveling in free space.

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Unfortunately, I don’t know enough to intelligently comment on this. I was largely under the guidance of my professor. However, I can tell you that in my modeling I used the paraxial approximation and that the light was linearly polarized. It was my understanding that only circularly polarized light carried intrinsic angular momentum (https://en.wikipedia.org/wiki/Spin_angular_momentum_of_light...).

Also, I would agree with you that in a uniform electric field, a single E vector in isolation would appear to produce a torque on a point some distance away. But if the rest of the field is considered, the net torque at that point would be zero, right?

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