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On quantum sets of the multicoloured-graph approach to contextuality

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 نشر من قبل Marcelo Terra Cunha
 تاريخ النشر 2021
  مجال البحث فيزياء
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It is well known that certain measurement scenarios behave in a way which can not be explained by classical theories but by quantum theories. This behaviours are usually studied by Bell or non-contextuality (NC) inequalities. Knowing the maximal classical and quantum bounds of this inequalities is interesting, but tells us little about the quantum set Q of all quantum behaviours P. Despite having a constructive description of the quantum set associated to a given inequality, the freedom to choose quantum dimension, quantum states, and quantum measurements makes the shape of such convex bodies quite elusive. It is well known that a NC-inequality can be associated to a graph and the quantum set is a combinatorial object. Extra conditions, like Bell concept of parts, may restrict the behaviours achievable within quantum theory for a given scenario. For the simplest case, CHSH inequality, the NC and Be



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