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Landauer Limit Demonstrated

Scientists show that a 50-year-old principle limiting future CMOS computing is real: Erasing information gives off heat

4 min read

7 March 2012—Physicists in Europe have experimentally demonstrated, for the first time, that a theoretical principle limiting modern-day computing is real.

In 1961, Rolf Landauer posited that the act of erasing a bit of information gives off an amount of heat related to the temperature and Boltzmann’s constant—a total of 3 x 10-21 joules at room temperature. Among other things, the theory has been used to address the famous problem of Maxwell’s Demon, a thought experiment that suggested a minute monster could create energy for free by sorting particles by their speed, in apparent violation of the laws of thermodynamics. Prior to 1982, when IBM’s Charles Bennett applied Landauer’s theory to the problem, the thinking was that the demon’s act of making measurements produced heat, eliminating the violation. But Bennett argued that heat was produced because the demon had to erase a bit of information in its memory in order to sort each particle.

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Why Functional Programming Should Be the Future of Software Development

It’s hard to learn, but your code will produce fewer nasty surprises

11 min read
A plate of spaghetti made from code
Shira Inbar

You’d expectthe longest and most costly phase in the lifecycle of a software product to be the initial development of the system, when all those great features are first imagined and then created. In fact, the hardest part comes later, during the maintenance phase. That’s when programmers pay the price for the shortcuts they took during development.

So why did they take shortcuts? Maybe they didn’t realize that they were cutting any corners. Only when their code was deployed and exercised by a lot of users did its hidden flaws come to light. And maybe the developers were rushed. Time-to-market pressures would almost guarantee that their software will contain more bugs than it would otherwise.

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