Luca Turin, an eccentric scientist whose nose has the olfactory equivalent of perfect pitch.

Until Turin came along, most people thought scent came from a molecule’s shape. Each molecule has a unique configuration of bumps and curves. When a lemon’s citral molecule, for instance, hits the receptors in our noses, those receptors recognize the particular ridges and valleys, and can provide our brain with one clue about the identity of the fruit being sniffed.

Turin, though, doesn’t buy the shape theory. It is molecular vibrations, he insists, that are responsible for smell. A scientific polymath with a Ph.D. in physiology and biophysics from the University of London, Turin also has a rarefied hobby: perfume.
The smell industry generates $11 billion a year.

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