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The answer to this question implies that a future change in particle A will cause an immediate related change in particle B. Does this include destruction of the particle by decay or other means (e.g. throwing it into the LHC)?

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    $\begingroup$ Good question; in the relational interpretation I would have thought so, as all interactions count as observations; I'm not so sure about others, for example the mainstream Copenhagen interpretation; this is where what we count as an observation is important. $\endgroup$ Commented Dec 3, 2017 at 22:11

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Your understanding of entanglement ist wrong. "A future change in particle A will cause an immediate related change in particle B" is not true. When one particle changes, the other doesn't. Entanglement is simply non-classical correlations. These correlations have been set up in the past - usually by interactions of the involved "particles". In that sense, you could answer your question by saying that entanglement is "static".

Since decay of a particle is a spontaneous process, when one particle is entangled to another and it decays, the other particle doesn't (or if it does, it's a coincidence). If you destroy one half of an entangled pair, the other one remains untouched.

There is a simple test to see whether something could in principle work with entanglement or not: You cannot, under no circumstances, transmit information faster than light. If the forced destruction of one particle would cause the immediate destruction of the other, you could use that to transmit information (I send the information that I destroy the particle or I don't).

The reason you cannot transmit anything faster than light is because entanglement is "just" correlations, in other word, any "weird behaviour" at later times has to be determined when the particles interacted in the past.

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