Polarized light: Where did the magnetic field go?

[Gauss44]

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Many of the diagrams of polarized light (including TBR's) seem to show light with an electric field and a magnetic field approaching the polarizing filter, but only an electric field coming out of the filter. Where did the magnetic field* go?

*The magnetic field associated with the light that makes it through the filter.

 

[sazerac]

It's just a bad diagram. The magnetic field is still there. It has to be. You know it is still there for two reasons:

Light gets through, and light by definition is both an electric and magnetic field.

Even if the magnetic field was gone, a changing electric field creates a magnetic field. (And vice versa, a changing magnetic field creates an electric field)

 

[Gauss44]

It's just a bad diagram. The magnetic field is still there. It has to be. You know it is still there for two reasons:

Light gets through, and light by definition is both an electric and magnetic field.

Even if the magnetic field was gone, a changing electric field creates a magnetic field. (And vice versa, a changing magnetic field creates an electric field)

Thanks, that's exactly what someone else told me recently. That most of those diagrams only include the electric field. The magnetic field is still there, perpendicular as always, just not in the diagram. The magnetic field just passes right through the polarizing filter as long as it is on the same wave as the correctly oriented electric field (that makes it through).

I didn't know that previously, just figured it out thanks to you and that other person - now I've heard essentially the same thing twice. I use to wonder if the magnetic field got reoriented parallel to the electric field or removed somehow.