Entanglement

Schrödinger coined a term — “entanglement” — the wave functions of any two interacting objects, including observer and observed, get wove into one.

This puts a researcher probing the subatomic world into a position similar to that of one water droplet trying to deduce the dimensions of another by touching it: Since the end result is one big droplet, the observing droplet can work out the volume of the observed (by subtracting its own initial volume from that of the big droplet) but can’t glean its original shape. Entanglement could be responsible for keeping objective reality behind a veil.