Quantum reality, in other words, remains ambiguous until measured. The reality of common perception is thus merely a definitive-looking veneer obscuring the internal workings of a highly uncertain cosmos. Which is where Einstein drew a line in the sand. A universe of this sort offended him; he could not accept, as he put it, that "the Old One" would so profoundly incorporate a hidden element of happenstance in the nature of reality. Einstein quipped to his quantum colleagues, "Do you really think the Moon is not there when you're not looking?" and set himself the Herculean task of reworking the laws of physics to resurrect conventional reality.
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