Quantifying causal influences in the presence of a quantum common cause
- URL: http://arxiv.org/abs/2007.01221v1
- Date: Thu, 2 Jul 2020 16:07:18 GMT
- Title: Quantifying causal influences in the presence of a quantum common cause
- Authors: Mariami Gachechiladze, Nikolai Miklin, and Rafael Chaves
- Abstract summary: We introduce a general framework able to estimate causal influences between two variables.
We show that every pure bipartite entangled state violates the classical bounds on causal influence.
- Score: 0.9176056742068814
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Quantum mechanics challenges our intuition on the cause-effect relations in
nature. Some fundamental concepts, including Reichenbach's common cause
principle or the notion of local realism, have to be reconsidered.
Traditionally, this is witnessed by the violation of a Bell inequality. But are
Bell inequalities the only signature of the incompatibility between quantum
correlations and causality theory? Motivated by this question we introduce a
general framework able to estimate causal influences between two variables,
without the need of interventions and irrespectively of the classical, quantum,
or even post-quantum nature of a common cause. In particular, by considering
the simplest instrumental scenario -- for which violation of Bell inequalities
is not possible -- we show that every pure bipartite entangled state violates
the classical bounds on causal influence, thus answering in negative to the
posed question and opening a new venue to explore the role of causality within
quantum theory.
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