Is Quantum Information Theory the Only Way to Handle Multipartite Entanglement?

[Mordred]

Is Quantum information theory the only theory that handles multi partite entanglement? I have been digging through the net but the only papers I have come across are quantum information theory based.

Though I don't have an issue with QIT, I would prefer to study examinations done with standardized QM or QFT operators, matrices and tensors.

If anyone knows of good links under QM/QFT would be appreciated. (I always like to cross study multiple methodologies for the same application)

 

[Mordred]

Update I am getting better hits by searching under GHZ states, in so far as to locate how to handle 3 and 4 entangled particle states. At least in these cases their are applicable experiments performed