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Why do jewellery chains put in a box together become so tightly knotted on themselves, and each other, that it is impossible to unknot them?
David Muir
Edinburgh, UK
A jewellery chain, like everything else in the universe, is subject to the second law of thermodynamics. This states that the entropy (disorder) of an isolated system will increase over time. A box of necklaces, neatly arranged, can only become more disordered (higher entropy) through any random movement of the box, as there are billions of tangled configurations and few ordered configurations (low entropy), and probability is the driver.
As the necklaces become more tangled, there is the likelihood that loose knots can form and, once formed, friction makes it highly improbable that a loose knot will randomly untie itself. Motion in the rest of the necklace is more likely to cause tightening of any knots. It isn’t impossible to untie these knots as the correspondent suggests, but to move from a high-entropy situation to a lower-entropy state requires outside input: in this case, human effort, dexterity and patience.
When you start looking, you find that entropy is all-pervasive. The second law of thermodynamics dictates that when you open a bottle of perfume, it is much more probable that the scent molecules will spread throughout the room rather than spontaneously find themselves all back in the bottle. Likewise, glass breaks easily, but shards are unlikely to reform a recognisable article.
Conrad Jones
Llansteffan, Carmarthenshire, UK
The chains are inanimate objects, so they will only become tangled if shaken about in their box, such as in a suitcase put through an airport baggage handling system. Further, even this won’t tighten them. My guess is that this happens when their owner is rushing to dress for dinner in their posh holiday hotel, and rashly pulls on one, which tightly tangles on the others. The solution is to send your partner to the hotel bar for two toothpicks (with cocktails if you like) and, maybe using the magnifying app on your mobile phone and with a good amount of patience, use them to gently pull the chains apart. Oh, and send for room service, as this will take some time. My next tip would be to use those clever cloth jewellery bags, which at least keep items separate.
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