Can information be turned into energy?

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These articles are part of our Information about information project. We asked Seth Lloyd, an expert on information at the Massachusetts Institute of Technology, the question above and here is an answer. We also bring you two related articles from FQXi who are our partners on this project. Happy reading!

Satanic science — There's no doubt that information is power, but could it be converted into physical energy you could heat a room with or run a machine on? In the 19th century James Clerk Maxwell invented a hypothetical being — a "demon" — that seemed to be able to do just that. The problem was that the little devil blatantly contravened the laws of physics. What is Maxwell's demon and how was it resolved?

If Maxwell's demon could work, then it would blatantly contravene the second law of thermodynamics. The law says that the entropy, a measure of the information in a system, never decreases as long as the system is left alone. Here are two articles from the FQXi website that further explore the role of the second law and its links to entropy and information theory.

The curious case of the quantum arrow of time — The second law of thermodynamics is often used to explain why time has a direction. It's the higher entropy — the greater disorder — that distinguishes the future from the past. But could there be another explanation for time's arrow, one that works at the level of individual particles? And could it be found using the theory of information?

Why did nature choose quantum theory? — To create energy from information you would need to break the second law of thermodynamics — that's impossible in the real world, but could theories that do break it shed light on why nature is the way it is?


In Richard Feynman's book "Five Easy Pieces", Feynman describes a particular picture of particles emmited after a collision in which he points out a particular particle path that he says is a meson travelling backwards in time.

In my humble opinion, if Feynman is right, then the second law of thermodynamics is not always true.

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