What Is The Mysterious 'Global Hum' — And Is It Simply Noise Pollution?

What Is The Mysterious 'Global Hum' — And Is It Simply Noise Pollution?
Up to 4% of people are said to hear a strange low-pitched noise known as the Hum, but no source has ever been found. City life is one possible cause.

March 14, 2019 at 02:50AM
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