How to Measure Entangled Photons in the 45/135 Basis with Wave Plates and PBS?

StevieTNZ
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In regards to measuring two photons in the 45/135 basis using 22.5 wave plates and PBS orientated in the H/V basis:

Is it with the entanglement |H>|V> - |V>|H>, with the wave plates:
H -> 45
V -> 135
so
|45>|135> - |135>|45>
And back again using a PBS:
|H>|V> - |V>|H>

So getting |H> at the PBS indicates that the photon passed a '45 degree test'? Likewise with |V> indicating the photon was tested in the |135> polarisation, and it 'passed'?

When we measure in the 45/135 basis with four photons entangled as |H>|V>|V>|H>-|V>|H>|H>|V>, how do we tell with the PBS whether we subjected each photon to a test in 45 or 135 basis, when |H>|V>|V>|H> could be |135>|45>|135>|45> or |45>|135>|45>|45>?
 
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