Professor teaches children inside secrets of computers

Chirstopher Bishop, a computer science professor at the University of Edinburgh in Scotland, told children attending his Royal Institution Christmas Lecture on Friday that the formidable enemy of computers obstructing the machines' development is the heat generated from microchips inside.

The Royal Institution Christmas Lecture is an annual event in Britain held since 1825 to convey the appeal of science to children. Since 1990, the lecture also has been delivered in Japan each summer.

The theme of this year's event was to discover the secrets of computers. In the lecture, titled "Breaking the Speed Limit," held at Bunkyo Civic Hall in Tokyo, Bishop said computers have roughly doubled in performance every two years or so over the past 50 years.

Bishop said such amazing improvements have been made possible because of microprocessors that perform complex calculations in less than a nanosecond, or one-billionth of a second.

"But a couple of years ago we hit a big problem, which threatened to stop further growth in the speed of microprocessors," Bishop said.

According to Bishop, microprocessors are made of millions of switches called transistors, and when transistors switch between on and off, they use power and produce heat. Increasing microprocessor speed also means they produce more heat per unit area.

"If we continued to double the speed of processors every two years, then within 10 years the heat density would equal that at the surface of the sun," Bishop said.

Visitors enjoyed the lecture, which also featured various experiments.

Tomomi Shibazaki, 16, of Iruma, Saitama Prefecture, who attended the lecture with a friend, said: "I was wondering why my computer becomes hot when I use it. I'm glad I was able to learn the reason why at today's lecture."

The event was organized by The Yomiuri Shimbun, the British Council and the Japan Science and Technology Agency.