It's a big chunk of confirmation bias (you don't remember all the times when that doesn't happen) and all sorts of less obvious behavioral correlations, like, i

It's a big chunk of confirmation bias (you don't remember all the times when that doesn't happen) and all sorts of less obvious behavioral correlations, like, if you tend to talk to someone weekly, and it's been a week since the last time, it wouldn't be surprising to have them reaching out to you around the same time you're thinking of them. I think this also holds up with how ad tracking aims to hoover up all sorts of data to find correlations. There are probably a lot of non-obvious correlations in there, which causes ads to sometimes eerily seem to read minds. These same correlations may cause people to exhibit very similar thoughts without needing to invoke quantum entanglement.