The New Thermodynamic Understanding of Clocks

In 2013, a masters student in physics named Paul Erker went combing through textbooks and papers looking for an explanation of what a clock is. “Time is what a clock measures,” Albert Einstein famously quipped; Erker hoped a deeper understanding of clocks might inspire new insights about the nature of time. But he found that physicists hadn’t bothered much about the fundamentals of timekeeping.

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