Entropy: Why the Arrow of Time Points Forward

826001492, Feb 11, 2026

Physics doesn't care if time runs forward or backward in its equations—except when it comes to entropy. The second law of thermodynamics says that in a closed system, entropy tends to increase. That gives us a direction for time: things tend to get more disordered.

Why was the past more ordered? That’s still an open question, tied to the initial conditions of the universe. What we do know is that every time you mix cream into coffee or break an egg, you’re watching entropy increase. The universe is slowly winding toward equilibrium.