Mpemba effect
Efecto Mpemba
- Date
- 1963 (publicado en 1969) · confidence medium
- Place
- Magamba, Tanga Region, Tanzania
- Credited to
- Erasto Mpemba and Denis Osborne
- Field
- Cosmos & Earth
⚠️ Disputed: the sources disagree.
What was discovered
In 1963 the Tanzanian schoolboy Erasto Mpemba noticed that a hot ice-cream mix froze before a cold one. With Denis Osborne he published the phenomenon in 1969, now called the Mpemba effect, still without a unanimous explanation.
Aristotle, Francis Bacon and Descartes alluded to something similar; the effect is not always reproducible in water and its robust existence is debated, though shown in simple models (Lu and Raz, 2017).
What it led to
- research on faster-cooling hot water (2016-2020)
- debate over the effect in nonlinear systems
- an example of school-level citizen science