Astronomy

Isn't it talking about it here?

As light travels through the Universe, it interacts with the matter within it, and with electrons in particular. (Remember, light is an electromagnetic wave!) If the light is polarized in a radially-symmetric fashion, that’s an example of an E-mode (electric) polarization; if the light is polarized in either a clockwise or counterclockwise fashion, that’s an example of a B-mode (magnetic) polarization. Detecting polarization, on its own, isn’t enough to show the existence of super-horizon fluctuations, however.

Also, it is long, yes, but it doesn't repeat itself like most Ai written articles. I'd say the author is just taking their time to spell the concept our in detail. Could have been said quicker and more efficient, I'll agree on that tough.