Ricerc@Sapienza

The Einstein-Podolsky-Rosen (EPR) entanglement of a neutral K-meson (kaon) pair enjoys the peculiar quantum behaviour of mixing, charge-parity CP violation (C charge conjugation, P parity) and two non-orthogonal eigenstates of definite time evolution KL and KS with very different lifetimes. The dynamics of this "strange entanglement", experimentally accessible at the Phi-factory, makes possible the search for novel phenomena not accessible in any other system, i.e. at interference times and at decoherence times of the single partners after their disentanglement, in order to unveil the nature of the correlation between the two neutral kaons. Until now, the studies have been concentrated on the single kaon intensity distribution between the two decay times t1 and t2 with Delta t = t2-t1 > 0. Here we focus on the study of the two single time distributions, before each decay, which are physical in both senses: "from past to future", leading to the state of the living partner at time t2 from the observation of the first decay channel at t1, but also "from future to past", leading to the past state of the decayed kaon at time t1 from the observation of the second decay channel at t2.
The latter constitutes a surprising novel effect, which leads to the affirmative answer to the title: it does, the past decayed state depends on the result of the future measurement for the living partner.
This effect has been discussed for the first time in a very recent work; the deepening of its theoretical implications and its experimental investigation which might lead to its first observation are the subject of the present proposal.