Answer found for why like-charged particles sometimes attract each other

Magnets

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It’s not just opposites that always attract as new research confirms an observation that has puzzled scientists for over 80 years

Similarly charged particles have been found to sometimes attract, rather than repel each other – something that contradicts textbook expectations and has important implications for chemistry and biology.1 The new results help to solve a puzzle that has bemused scientists for the best part of a century.

‘We are taught in high school that like charges repel and this oft repeated lesson is accepted as fact,’ says Seth Fraden at Brandeis University in the US, who wasn’t involved in the study. ‘But stretching over a period of decades, there have been a few rare observations of the opposite in which water-borne colloids with the same negative charge attract .’ Irving Langmuir is credited with one of the first investigations of this phenomenon in 1938.