- It took about 40 years to find it, but scientists at Hewlett-Packard said on Wednesday they discovered a fourth basic type of electrical circuit that could lead to a computer you never have to boot up.
The finding proves what until now had only been theory -- but could save millions from the tedium of waiting for a computer to find its "place," the researchers said. Basic electronics theory teaches that there are three fundamental elements of a passive circuit -- resistors, capacitors and inductors.
But in the 1970s, Leon Chua of the University of California at Berkeley, theorized there should be a fourth called a memory resistor, or memristor, for short, and he worked out the mathematical equations to prove it.
Now, a team at Hewlett-Packard led by Stanley Williams
has proven that 'memristance' exists. They developed a mathematical model and a physical example of a memristor, which they describe in the journal Nature.
"It's very different from any other electrical device," Williams said of his memristor in a telephone interview. "No combination of resistor, capacitor or inductor will give you that property."
Williams likens the property to water flowing through a garden hose. In a regular circuit, the water flows from more than one direction.