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A recent experiment shows how quantum mechanics can make heat flow from a cold body to a hot one, an apparent (though not real) violation of the second law of thermodynamics.
Time isn’t just another dimension, argues Tim Maudlin. To make his case, he’s had to reinvent geometry.
There’s more than one good way to bring order to our unruly, seemingly arbitrary calendar.
How our society defines years, months and weeks can seem frustratingly arbitrary. Can you bring order to our unruly calendar?
The effort to unify quantum mechanics and general relativity means reconciling totally different notions of time.
Insights about time’s arrow from a liquid crystal universe.
What insights can an LCD display give us about time’s arrow?
According to our best theories of physics, the universe is a fixed block where time only appears to pass.
Bizarre quantum bonds connect distinct moments in time, suggesting that quantum links — not space-time — constitute the fundamental structure of the universe.