Maelin comments on Decoherence as Projection

[Maelin]

So I was following this post all the way through, right up until I got to this part:

There are ways to use a polarizer to split a beam into two components, rather than absorbing a component and transmitting a component.

It isn’t explained what actually occurs here and I’ve been unable to decypher the following paragraphs as a result. Could this be clarified, please?

[[deleted]]

Combine a beam splitter with two polarizing filters.

EDIT: I read the relevant paragraph, and what I described above probably doesn’t work. However, not all is lost: there is a device that more precisely does what Eliezer says: Beam-splitting polarizers.