Beyond Bell: Falsifying Direct Causation

报告题目：Beyond Bell: Falsifying Direct Causation

报 告 人：Professor Valeri o Scarani, National University of Singapore

时    间：    2026年4月21日 (星期二) 11:00-12:00

地    点：    南楼 109 （South Building 109）

Abstract: According to Reichenbach's criterion, correlations may come through two structures: common cause, or direct causation. For the case of correlations obtained by measuring entangled systems, Bell famously excluded any explanation relying only on a common cause. A few years ago, we first intuited and then finally proved that direct causation can also be excluded up to the extreme case of influences with infinite speed in a preferred frame (or similar, more complex variations). More precisely, if quantum correlations were due to influence at finite (albeit superluminal) speed, then it would be possible even for observers to communicate faster than light. The argument uses three or more particles. I shall review these ideas, with the hope that some could be tested in a proof-of-principle experiment.

报告人简介：Valerio Scarani is Professor at the Department of Physics and Principal Investigator at the Centre for Quantum Technologies (currently serving as its deputy director) at the National University of Singapore. Over the years, his theoretical works has covered several areas, notably quantum cryptography and Bell nonlocality (a topic for which he has written a comprehensive treatise, Oxford University Press 2019), from foundations to collaborations with experimental groups.