Why We're Building Underground Telescopes

The video discusses the evolution of telescopes, focusing on underground telescopes designed to detect gravitational waves. Unlike traditional telescopes that collect light, these new telescopes use laser interferometry to measure space-time distortions caused by gravitational waves. The video highlights the success of LIGO and Virgo, and introduces KAGRA and the proposed Einstein Telescope, which aim to improve sensitivity and detect a wider range of frequencies. These advancements could provide insights into the universe's earliest moments and test theories of gravity.

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