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Time is not a river, but a one-way street ⚡ экспресс

Original: "Constraints on Reversing the Thermodynamic Arrow of Time from Black Hole Thermodynamics, Wormholes, and Time-Symmetric Quantum Mechanics"
· Kevin Song, John Zhang
arXiv:2512.03380 · 2025-12-03 · CC BY · ⏱ 1 min · General Relativity
Scientists have shown that even black holes and wormholes cannot reverse the flow of time.
Abstract

The thermodynamic arrow of time points from the past to the future due to the relentless growth of entropy. But can black holes, traversable wormholes, or quantum approaches with reverse causality temporarily reverse this growth? A unified informational framework ("Global Entropy Transport") shows that any local decreases in the entropy of matter and radiation are compensated by changes in horizon area and correlations. Entropy doesn't vanish—it just gets redistributed, like in a zero-sum game where a gain in one place means a loss in another. The observed arrow of time remains irreversible within semiclassical gravity.

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Time is a one-way road: events race forward with no U-turn allowed. The arrow of direction is governed by entropy — a measure of disorder, which only grows in the Universe, like a traffic jam at rush hour. You can clear one intersection, but the overall congestion only gets worse.

Even the wildest “detours” — black holes and wormholes in curved spacetime — won’t let you drive the wrong way. Scientists applied the method of global entropy accounting (Global Entropy Transport) and proved: these objects just shuffle disorder from one pocket to another, like tidying one closet but leaving the whole house a mess, while the total chaos in the Universe keeps growing.

You can clean up one corner, but the whole house gets cluttered relentlessly.

The striking conclusion: the entropy of a typical black hole is billions of times greater than that of an ordinary star — these monsters are veritable warehouses of disorder. The arrow of time is as solid as asphalt: even fanciful wormholes can’t make it show the way to the past.

🎯 The entropy of a black hole depends on the area of its surface (event horizon), not its volume — this discovery by [scientist:Jacob Bekenstein]Jacob Bekenstein[/scientist] gave rise to the idea of a holographic Universe.

🎬 In Greg Egan’s novel ‘Schild’s Ladder,’ the characters try to cheat thermodynamics, but the arrow of time remains relentless.

Scientists
Stephen HawkingJacob BekensteinAlbert EinsteinFritz ZwickyVera RubinBernhard Riemann
Tags
entropy black hole spacetime curvature
Laws
second law of thermodynamicsHawking radiationgravitational lensingBekenstein-Hawking entropyEinstein field equationsBoltzmann distribution
Original: arXiv:2512.03380 · CC BY · bridge42worlds