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I know that matter can be converted to energy through E=mc^2.

I also know that engery can be and has been converted to information through Landauer's principle (with Maxwell's demons).

Does this mean that I can take a brick and covert it into information? (It is irrelivent if there is no known process yet)

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'Matter' can not be converted to 'energy' according to E=mc^2. Both 'matter' and 'energy' can take on different forms or if you will manifest themselfs as different elementary particles. What kind of transformations are allowed is, however, governed by other laws of physics. Now, Landauer's principle, to my knowledge, states that it takes energy to perform irreversible transformations on 'information', e.g. erase it. From that one can certainly not conclude that energy and information can be converted into one another.

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You "know" wrong.

First and foremost, the $m$ in $E=mc^2$ does not stand for matter, but for mass. Mass is a property of matter, and energy is a process of matter and also of radiation. It should be clear that you cannot convert some object or substance into one of its properties. Converting matter into energy would be like converting stone into solidity. What $E=mc^2$ says is that energy and mass are not independent properties. Especially there's not a conservation of mass independent of energy conservation, and thus massive particles ("matter" can be transformed into massless particles ("radiation", especially electromagnetic radiation, sometimes wrongly claimed to be "pure energy") provided this conversion does not violate another conservation law (e.g. an electron cannot decay into electromagnetic radiation because that would violate the conservation of charge; however an electron and a positron can annihilate into electromagnetic radiation, because that doesn't violate any conservation laws).

Now given that you're wrong about conversion of matter to energy, it will probably not be a big surprise to you that also a conversion of matter to information is not possible, and would not make sense.

Note that even if, as some people do, you consider information instead of matter to be the fundamental property of the universe, that doesn't change the fact that a conversion of matter to information does not make sense: In that case, the brick is already information, and therefore it still doesn't make sense to convert it into information.

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Yes of course. In fact we store information nowadays by reconfiguring matter. e.g., grooves on a record, arranging magnetic material on hard disk. You can take bricks to write letters.

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This is not what I am talking about. I mean can I replace matter with information (remove matter from the universe) in the same way that I can replace it with energy by touching it to antimatter. This is an issue in Information Theory. – user3465829 Apr 21 '14 at 23:46
Information needs to be encrypted into some thing physical. There is no such thing as information without Energy or matter. – user3394040 Apr 22 '14 at 15:54

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