Brussels, 24 Sep 2002
University science professors in the USA have come up with an inventive way to liven up lessons - by showing their students how to transmit electric signals at least four times faster than the speed of light using only basic lab equipment.
Scientists have managed to send light signals at faster than the speed of light for decades, but only using elaborate, expensive scientific equipment.
But the New Scientist online reports that physicists from the Middle Tennessee State University have managed to break that speed limit over distances of almost 120 metres using basic equipment worth the equivalent of €511.
The two professors, Jeremy Munday and Bill Robertson, constructed a 120-metre-long cable by interchanging six- to eight-metre-long lengths of two different types of coaxial cable, each of which had a different electrical resistance. They then linked the cable up to two signal generators - the first generated a fast wave, the second a slow wave. These waves then interfere with one another to produce electric pulses, which can be viewed using an oscilloscope.
Pulses - whether electrical, light or sound - can be pictured as a group of tiny intermingled waves. The energy from this 'group pulse' rises and falls over space, with a peak in the middle. The varying electrical resistances in the cable cause the waves in the pulse's rear to reflect off each other, moving the pulse's peak forward.
By observing the pulse's strength and speed using the oscilloscope, the young scientists confirmed that they sent the signal's peak speeding through the cable at more than 4 billion kph. "It really is basement science," Robertson told the New Scientist online. In fact, the apparatus is so simple, that Robertson once managed to set up from scratch in less than 40 minutes.
Dr. William Robertson
More information on this subject:
See also the EU's Young Scientist Contest which promotes this kind of innovation in education, as well as co-operation and interchange between young scientists.