Detecting Entanglement in Alice Without Measuring Bob

[shifty123]

First time poster:

Is there any math out there that prohibits the following scenario from taking place:

Alice and Bob are entangled. Is it possible to detect that Alice is entangled, without measuring Bob and without destroying the entanglement (or causing decoherence)?

Note: I am not trying to detect any joint information shared between Alice and Bob, just the state of Alice's entanglement without looking at Bob.

 

[DrChinese]

First time poster:

Is there any math out there that prohibits the following scenario from taking place:

Alice and Bob are entangled. Is it possible to detect that Alice is entangled, without measuring Bob and without destroying the entanglement (or causing decoherence)?

Note: I am not trying to detect any joint information shared between Alice and Bob, just the state of Alice's entanglement without looking at Bob.

Welcome to PhysicsForums, shifty123!

No single (or repeated) measurement on Alice will indicate the presence of entanglement. That is because entanglement is a joint state. I.e. there are no observables at the individual particle level that reflect entanglement.

 

[shifty123]

Thanks!