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Is Information described by physics?

  1. Dec 9, 2009 #1
    My question uses this definition of information:

    - An intangible and dimensionless thing that is not energy nor matter.
    - Can be an arrangement of matter (a typed/printed letter on a page) or a pattern of energy over time (music on the radio).

    I hear physicists talk about "information" sometimes. Are there any prominent theories on information itself. Such as how it can be represented by any substance, matter, energy. Are there any attempts at formalizing the science of information itself, irrespective to its associated physical systems? Most of the time I read about "information" it is taken as a given, like some fundamental quality of reality, and used in conjunction with other theories, such as relativity which says no information can be transmitted faster than c.

    Would everyone here agree that information is not energy and it is not matter, but something independent of each? And would everyone agree that information could be theoretically understood regardless of any rules of physics? Lastly, can we agree that (our) physics governs how information is transmitted, but not the truth value of that information. I know we can agree on that one, but stretching it further: can we agree that information is something that is irrespective of physics and only realizable as a result of physics, but not utterly dependent on our particular laws of physics to be expressed.

    This is not my intention to be metaphysical, but a serious question. If something isn't matter and energy, but abstractions, what is the science that deals with this? Computer science comes close, and that is my field, but it seems much more fundamental than any of the disciplines, even mathematics. For if we could not express the simplest forms of information we wouldn't even know anything at all.

  2. jcsd
  3. Dec 9, 2009 #2
    How could you describe what a sunset was to a universe where suns could not exist, or possibly even light does not exist? Does information have any substance outside the physical system which "created" it?
  4. Dec 9, 2009 #3
    I argue that it does have substance, in that it is the only fundamental quality of any possible reality that can declare truth. The fact that truth can be represented in any medium, at any scale of reality, and any type of energy. You can write "SOL" on paper, as bits in a computer, as oscillating pulses of EM radiation, or which ever. It comes down to the observer's ability to interpret those patterns, which is what information ultimately is, to be meaningful. What allows it to be objectively substantive is that everyone with reasonable faculties can agree as to what an arrangement says if at least one person can define it as such, and as long as that pattern is preserved from entropy.

    My question is, does physics work with information itself. Is there a set of laws and predicates that handles the fundamentals of information as a concept notwithstanding the systems of reality they are enmeshed with?
  5. Dec 9, 2009 #4
    Information only exists in our minds. Since we live in this physical universe, we must use certain physical forms (patterns of matter and energy) to represent these abstractions. Now this informaiton we have inside our heads isn't true at all: it's just an interpretation. To use physics as an example, we have the theories of GR, QM, etc, and these theories do very well for us, but they only explain some of what's really going on.

    In a way, entropy and probability deal somewhat with information. Entropy talks of ordered and disordered states, but what does that mean really? Is the state where the monkeys have typed "To be or not to be, that is the question." really any different or less likely than "Zomf fk wi nhs uge o'ms sun qkk ssss uwn"? Only to us. We label some 'ordered' states as special, and group 'disordered' ones together as being the same. Granted, most of what we call 'ordered' is in a higher energy state than 'disorder', that's just an artifact of the fact that high energy states generally are more usefull to us, and they're not always higher anyway.
  6. Dec 9, 2009 #5
    I would like to think that entropy is one of the most fundamental concepts, even more so than information itself. Why? Because entropy can apply to every type of system we can conceive, whether its an ice cube or file compression information limits. Without order in a system, information would never be coherent enough--thus the fundamental presupposing of information.

    Now, addressing the subjective nature you brought up. This is a very good argument, and one that I did mention; that all information is inherently subjective. However! That information does objectively exist as an ordered pattern. It does not lose its truth value simply because we can not understand it: a book is not untrue anymore simply because you need new glasses. The book remains true, if it was originally true, until entropy makes it untrue.

    It is philosophical idealism to presume that we define the absolute or its representations. Surely you agree with my book parable? But you would argue that not even the book is true. That is incorrect. If the book were never true, it would be incomprehensible always, forever, to anyone, regardless. The only absolute untruth is maximum entropy; nothing, non-existence, maximum equilibrium.

  7. Dec 9, 2009 #6
    Well, the book can be said to only partially be true, because the informaiton it contains can only be an approximation of the universe. It is more true than the maximum entropy state, but less true than a better book, or the ultimate ordered state.

    Does the book become untrue if you need new glasses? No, but to you it becomes inaccessible and loses its meaning.
  8. Dec 9, 2009 #7
    Indeed, loses meaning, not truth value. Critical distinction and I am very pleased to see you agree on that. I mangled my own example by saying that entropy makes it untrue! I should actually sleep before doing questions!

    The real question then, is if information is fundamental? And what is fundamental? If we decide by science and physics, then it is that which is of a lower order of organization and still remains discretely identifiable; that which makes other things.

    But is information more fundamental than the science of physics? Well yes, as the science of physics is information itself. Is it more fundamental than reality itself, our universe? That depends on what the information is, and if it comes to pass that alternative realities can exist or not. I would say that if we have the facts right about reality, like that gravitation does exist, then this is a part of the absolute truth in regards to our particular reality and time. Like the book, it wouldn't stop being true simply because we removed this reality.

    So is it safe to say that information is fundamental to everything? Another way of saying this would be: if information can not be represented, then surely reality is at an end and such a universe is but a voided container of either pure entropy or nothingness -- essentially one in the same to any material or energy.

    But I didn't want to go down that philosophical deduction, even though it has made great logical sense in retrospect. I was wanting to know if there was a discipline in science that studied the nature of information specifically, outside the disciplines I am already familiar with.
  9. Dec 9, 2009 #8
    I haven't really studied it, but I thought I should point out that http://en.wikipedia.org/wiki/Information_theory" [Broken] does indeed exist as a formal field of study. You can actually derive/define entropy this way, so there really is a (presumably rigorous) connection there as well that, although as I mentioned I don't know much about it so I can't really comment intelligently.
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  10. Dec 9, 2009 #9


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  11. Dec 9, 2009 #10
    Outstanding, thank you for this.

    Thanks to all for the feedback!

  12. Dec 12, 2009 #11
    no such thing exists

    - then again mickey mouse 'exists' but he's described by physics as an image or interference patern
  13. Dec 13, 2009 #12
    i would say that information is the only thing that we know for certain exists. energy is just a way of describing certain aspects of the state of a system. the fact that it happens to be conserved makes it very useful. but its still just information about the system
  14. Dec 13, 2009 #13
    There is no interpretation of interpretations, there is no information about informations, there is no understanding of undestandings, how would you understand what understanding is, when to do so, you have to use the process 'understanding'? These are examples of circular reasoning and it might be better to treat certain concepts as 'fundamental' and stop asking further questions what they really are, or why they are the way they are. All aspects of Reality aren't really comprehensible, there is no available outside(god's) view to establish what those concepts really mean.
  15. Dec 14, 2009 #14
    That is not the same thing as defining what information is. And say that a fermion is fundamental is an assumption. It is fundamental now, but it may not be later. If that turns out to be the case, then we were wrong.

    Information is non-physical. I prefer to use the term information rather than energy; because, the word energy is enmeshed with concepts on physics. When someone says "energy is physical," what they are really saying is that it is described by physics, not that it is somehow solid or even necessarily perceptible.

    The problem is that information itself doesn't have to "exist." And I can see that you have carried this over from our other discussion on philosophy, but this wasn't a philosophical question. What I originally asked was from a physics standpoint, which is to ask, "does physics account for the concept of information itself, as an abstraction." And that answer was yes and no.

    The important distinction to make with information is that it is not synonymous with energy, by the physics formulas and definitions. It has a relationship, only in that information can describe energy, and that, in our universe, it takes energy to manifest information; however, this in no way requires that energy and information are exactly the same thing. There is nothing circular about this.

    Entropy being the absolute fundamental is self-evident. And I don't mean just the narrow thermodynamic explanation for entropy, but the broad concept of disorder. Information is the negation of that which is entropic. The laws of our Universe subsequently require that energy is needed to effect that as real. Information is, of course, physical, for us to be able to work with it and understand it, but there does exist an intangible realm of expression and abstraction, independent of the necessity that it is rooted in the laws of our particular physical reality.

    It isn't black and white. This like dynamics vs kinematics. The interplay between matter, that which is reducible, is not a physical thing, but only understandable as a temporal or spatial delta. This is a type of information, and it is this interaction to which I say, it is not tangible, but the "thing" that occurs as an interaction between the physical systems.

    [tex]\Delta[/tex]reality [tex]\rightarrow[/tex] a non-physical construct

    It isn't physical, it is an explanation of changes in a physical system.

    E != information, either.

    It takes energy to manifest information (order) in a physical system. But if you are dealing with a non-physical construct, the idea of energy as we know it, may not even remotely apply within the framework, except to explain how the system was created in the first place. It does not explain or provide details on the limits of information itself, how it changes, or how it decays. What we describe and quantize as energy in physics is therefor not synonymous with purely informational theories. It is only entropy that can apply, fundamentally to an understanding of a purely abstract informational system.

    It is also true that not every informational abstraction has to be manifested into a physical system as we know it, but can exist as a potential, or probability of emergence. While yes, ultimately, all existential information contained in this Universe, to our present knowledge, must be contained inside what we know as physical systems, that itself does not necessitate what information is. It is only a constraint for information for our particular Nature. This is particularly true of chaotic systems, where complex emergence of information occurs, leading to the perspective that information was in a potential state of all possible states at a given point of reference in the past, if one factors in contributions from other systems.
    Last edited: Dec 14, 2009
  16. Dec 14, 2009 #15
    No one knows what information is. There is no information without a perceiving mind, and this discussion is more appropriate for the philosophy forum, since no one knows how the mind works(perceives and processes information).

    Furthermore, you cannot do physics without assumptions, it simply isn't possible. You assume that an electron is fundamental and build a theory. If no experiement contradicts your assumption, then for all we know, electrons are fundamental.

    Do you have a proposition as to how to 'extract' information about what information is? I did not see you suggest a way to accomplish this.

    You have completely failed to get my point. The circular reasoning comes from demanding information about information(i have no clue how you got the idea i meant information was synonimous with energy). It isn't possible to understand what information fundamentally is, and as i suggested, it's best to treat it as a kind of fundamental but emergent capability of the human mind to put to use whatever it is that information is, and move on to phenomena we can say much more about.
  17. Dec 14, 2009 #16
    i think you are reading something mystical into his post that he never intended. i think the point is that we dont know what the fundamental nature of reality is. all we can do is describe reality. description is information.
  18. Dec 16, 2009 #17
    Thank you :smile:
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