More than two full generations of Moore's law (which says that the number of transistors squeezed on to a computer chip doubles every 18 months) have passed since the tech bubble burst, as have more than three generations of fibre-optics communications technology.

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Communications capacity on fiber optics will double every 6 months.

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Rare earth elements are also used for military applications, such as advanced optics technologies, radar and radiation detection equipment, and advanced communications systems, according to a 2011 research report by the US Government Accountability Office.

BBC: US to build $120m rare earth research institute