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Register a new userOn the non-locality of tripartite non-signaling boxes emerging from wirings
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It has been recently shown, that some of the tripartite boxes admitting bilocal decomposition, lead to non-locality under wiring operation applied to two of the subsystems [R. Gallego et al. Physical Review Letters 109, 070401 (2012)]. In the following, we study this phenomenon quantitatively. Basing on the known classes of boxes closed under wirings, we introduced multipartite monotones which are counterparts of bipartite ones - the non-locality cost and robustness of non-locality. We then provide analytical lower bounds on both the monotones in terms of the Maximal Non-locality which can be obtained by Wirings (MWN). We prove also upper bounds for the MWN of a given box, based on the weight of boxes signaling in a particular direction, that appear in its bilocal decomposition. We study different classes of partially local boxes and find MWN for each class, using Linear Programming. We identify also the wirings which lead to MWN and exhibit that some of them can serve as a witness of certain classes. We conclude with example of partially local boxes being analogue of quantum states that allow to distribute entanglement in separable manner.
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