HP makes memory from a once theoretical circuit
 

It's the tale of the lost circuit.

Thirty-seven years ago, Leon Chua, a professor at the University of California at Berkeley, mathematically theorized that scientific symmetry demands that there should be a fourth fundamental circuit. Engineers were already familiar with resistors (which resist the flow of electricity), capacitors (which store electricity), and inductors (which resist changes to the flow of electrical current), which can be combined to build more complex devices. The fourth circuit, which Chua called a "memristor" for memory resistor, would register how much current had passed.
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*Source: News.com (http://www.news.com/8301-10784_3-993...ag=nefd.lede)*

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