91av

Letter: For the record

Published 20 August 2025

Above its “entropy catastrophe” temperature, a solid has higher entropy than its liquid, so melting would break the second law of thermodynamics (2 August, p 16).

The pineal gland secretes melatonin (2 August, p 30).

Issue no. 3557 published 23 August 2025

91av issue 3557 cover

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