A Russian mathematician has rejected a $1m (£700,000) prize for solving one of the most challenging problems because he considers it unfair.
Grigory Perelman, 44, said yesterday that he told the Clay Mathematics Institute in Cambridge, Massachusetts, that he was turning down the prize for solving the Poincare conjecture, which has baffled academics for a century.
The reclusive Dr Perelman, who previously refused the prestigious Fields Medal, told Interfax news agency that he believes his contribution was no greater than that of the US mathematician Richard Hamilton, who first suggested a programme for the solution of the Poincare conjecture.
The Clay Mathematics Institute confirmed on its website that Dr Perelman had informed it of his refusal to accept the prize. The Poincare conjecture deals with shapes that exist in four or more dimensions.