Wheeler's delayed choice experiment.

Wheeler's delayed choice experiment is a double-slit experiment in which they change the setup while quanta traverse it, trying to understand when quanta change behaviour along the journey. Also, there's the quantum eraser experiment, and even a delayed choice quantum eraser experiment, in which some information (like which-way information) is acquired, but gets discarded later on, with no real consequences for the final pattern detected.

Quantum objects seem to be aware of all the changes, evolutions and configurations of the measurement setup since emitted, adapting their appearance to wave or particle “retroactively”. But we should remember that all the landmarks, checkpoints and obstacles they traversed are present for them when they get detected, just as if they were omniscient of everything that happened during their journey (because they are!) The spacetime interval we see doesn't exist for them but, at the same time, the actions we performed during that interval were part of what made them exist.

Entities sharing carriers feel connected, even when they get detected by different observers at different times and places. In a sense, any carrier detected has an associated volume of space where all events happening there “conspired” to make it exist at detection point. When this happens, it's as if the observer was dealing with emission point directly, with no considerations of time or distance involved. That's why two causally separated carriers can keep consistency even when they can't communicate: observers are interacting directly with the entanglement event when they deal with the related carriers.

After an interaction, we use our common sense (based on space and time) to try to understand how they knew all rearrangements and adapted their behaviour. The answers is they knew about the whole setup at once (be it a lab or a galactic cluster) because all the conditions that made them appear as they did were met.

Measurements and detections are fundamental parts of events, interactions and exchanges. Each detected entity tells the story of the whole spacetime interval that took place. If anything happening during the emission-absorption interval had been a bit different, then the carrier wouldn't be exactly the one perceived.

The same redundant spacetime information gets encoded once and again inside the massive number of matter interactions being detected at any given time. They all converge, “crystalizing” into a coherent image of the universe. A consistent causal reality. For each observer. Each time.