‘Are you familiar with the Millennium Prize problems?' Buhrman, who works at the National Research Institute for Mathematics and Computer Science and the UvA Institute for Logic and Language, begins telling us about his discipline with a question. As the year 2000 got underway, he says, the American Clay Institute formulated seven mathematical or physics problems. The institute put up a prize of one million dollars for the solution of each problem. ‘Clearly these were not just any problems. The first problem was recently solved. Perelman, a Russian, who found the solution is something of an exception: he refused the prize.'
Buhrman himself is working on one of the seven problems, the so-called P versus NP problem. ‘No not for the prize money. I had been working on it for much longer. It was the subject of my doctorate in 1993.' The problem is the leitmotiv of his research. ‘If you want to solve a mathematical problem with a computer program, the calculation involved takes a specific amount of time depending on the quantity of the data. Then you get your answer. Or you get no answer. That may be because arriving at an answer will take too long. Some calculations can take thousands of years to complete; so even a computer that works twice as fast won't help you much.' (UvA)