Quantum entanglement is a topic that often gets mangled in the popular press (much my to my torment), so it’s nice when a physicist writes about it.
[H]ere’s the problem: the first measurement does not cause anything to happen with the second system: they cannot be in communication in any way, because the distance between them is arbitrary. In other words, they could be separated by several parsecs without changing the outcome, so if they were actually passing information, that would be in violation of relativity. You can’t send signals faster than light using entanglement as a result: the only way you could kinda-sorta communicate is if you had two groups of researchers who agreed in advance on what the settings of their instruments would be before they parted company; no new information would be available, since the real communication takes place at light-speed or slower, before the measurements are even performed.
Fair warning: at the end of the post, under the heading of “What Entanglement Is Not”, the discussion loops back into the “everything is connected” kerfuffle.