Until the 1970s, public key cryptography was just an intriguing theoretical idea.

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The head of Nokia's research laboratory in Cambridge, Tapani Ryhanen, is keen to point out that Morph is a highly theoretical idea of what consumers might be expecting in a decade's time.

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The Germans regard this as a purely "theoretical" idea.

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But the idea remained merely theoretical for many years.

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Building on an idea floated earlier this year by theoretical physics guru and Nobel Laureate Frank Wilczek of MIT, a team led by UC Berkeley researcher Tongcang Li has created a schematic for a crystal with a fourth dimension -- movement in time.

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However, there are good theoretical reasons why an extension of unemployment benefits is not a good idea.

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