lived on planet Earth during the last 350 years, and about 5 million of them were mathematicians. None of them was able to solve the problem posed by Pierre de Fermat until Andrew Wiles turned up but this is a clear difference between humans and computers. However long you give a computer it would never be able to

ng as it crosses the many successive layers of warm air near the surface of the road, until it heads back up to your eye. The French mathematician Pierre de Fermat showed in ikso another way to understand this phenomenon. Light travels faster in warmer, less dense air than it does in colder air. Because the wa