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Absolute Zero: The Impossible Temperature Explained by Science

10/11/2025

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Summary

Story summary

Scientists say that absolute zero, defined as 0 Kelvin, cannot be reached because the third law of thermodynamics requires an infinite number of steps.
Refrigeration cycles and laser cooling can bring substances near absolute zero, but some heat remains.
The idea of negative temperatures is misleading because such systems are not colder than absolute zero and will release heat when placed in a normal environment.

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Story summary

Scientists say that absolute zero, defined as 0 Kelvin, cannot be reached because the third law of thermodynamics requires an infinite number of steps.
Refrigeration cycles and laser cooling can bring substances near absolute zero, but some heat remains.
The idea of negative temperatures is misleading because such systems are not colder than absolute zero and will release heat when placed in a normal environment.