What is the technical definition of "information"? I know what information is in a colloquial sense, and I know something about it's technical definition in the field of computer science, but I don't know what physicists mean when they use the word. Is information the same thing as light? Is it analagous to light? Is it a property of light? Matter?
I guess that information is change of state that is clearly distinguishable from some "random" change of state and caries a "meaning".
Eg. If you had an entangled pair of particles on this side of galaxy and another on other side of galaxy. Now you "wiggle" (change its state) one then the other one "wiggles" too - but you didn't send any information - since the other observer cannot know if the particle changed state because of your message - or it changed state "of its own accord". Thus you would still need to notify him of you wiggling the first particle eg. via photon - thus information only moves at the speed of light :)
Bear with my awful analogy - since I really don't know anything about physics :)
I just define it for myself as "If it can transmit information, it could also be used given enough technology to send any kind of data, such as a Microsoft word document."
That definition would probably work. Have a look at Feynman's lectures on computer science. He also investigates how much energy has to be used for computing. (Or to be more precise, how much entropy has to be created.)
