Demystifying Photons and Polarizers: Understanding Interaction and Measurement

[cragar]

Cant we shoot a photon thorough a polarizer without having the polarizer interact with it ?
Like all the ones polarized perpendicular to it will get blocked but the ones lined up will go through. But if the particle is not in a polarized state until we measure then how does this work?

 

[DrChinese]

It collapses to the polarization of the polarizer, which is arbitrary labeled H or V. A polarizing beam splitter passes both H and V, but in different output directions. A polarizing filter just passes V.

http://en.wikipedia.org/wiki/Polarizer

 

[cragar]

Ok so it is not in a state until it reaches the polarizer and it collapses it to that state.
thanks for your response.

 

[DrChinese]

Ok so it is not in a state until it reaches the polarizer and it collapses it to that state.
thanks for your response.

Also, there are times when it IS in a polarized state when it arrives a the polarizer. At that point, the polarization may be changed. Depends on whether it is in a pure state or a superposition. (A collection of particles in unknown pure states is called "mixed".)