Physics tricks could make for one-way soundproofing

One-way mirrors, which many of us know from watching police procedurals on TV, seem a bit magical–how does the mirror know which light to let through and which to reflect? The truth is, it doesn’t. The one-way mirror and its smaller cousin, the mirrored sunglass lens, rely on lighting imbalances for efficacy.

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Physics tricks could make for one-way soundproofing