What is information?

[RegisterMe]

So I've been bingeing on physics / maths videos again.... Thirty years or so ago, as an undergrad on a Systems Analysis degree course, I was quite proud of myself when I defined it as "meaningful data". Nowadays? That doesn't really cut the mustard anymore. As soon as you start thinking about "stuff", which "contains" or "embodies" information, falling into a black hole pretty quickly* you get to Planck Lengths and the Holographic Principle.

But put that to one side for the moment. What is information? Does it have a physical manifestation in your brain? If so, how does it get to somebody else's? What happens when I write down the US Constitution, somebody else reads it, and from that builds an entire society? How does that fit with the the Second Law of Thermodynamics / entropy?

I'm already confused, but I'm looking forwards to the comments, questions, and discussion that will ensue .


* where "pretty quickly" means "if you're a Nobel Laureate who understands this stuff".

[Vertigo 7]

My opinion is basically separating the metaphysical from the physical. You have the physical, that which is proven or disproved, that can be represented by simplistic t/f binary means. And then there's the metaphysical - theory, conjecture, speculation, etc., which I believe, is the basis for creativity and idea.

In your example of the constitution spawning a society, how to get from A to B, I would see the constitution as a mostly metaphysical starting point of an idea where by those that believe in it would perform actions in support of that idea. Where the physical components would be the thoughts that created the constitution, (if you're referring to the US constitution) would be all of the perceived wrongs of the British empire against colonial Americans. And the metaphysical components being how they envisioned society going forward. The masses then saying "Yep, I like it" and went with it.

So, I would say, the original definition of information being "meaningful data" could be expanded to say "meaningful data that has been proven or disproved that can inform new ideas"

[Observe]

Information requires consciousness (an observer) and sense perception. I am conscious that my sense of hearing perceives a sound. This is information. Usually, evaluation follows information. We may evaluate information as good, bad or neutral. After evaluation, we will take action or no action, depending on good, bad or neutral.

Information doesn't have to be external. Thought can be a source of information. My sense of thought perceives an idea. This too is information. I may decide on a course of action based on the information this thought has conjured in my mind.

Prior to processing, information is just awareness. It is "bare truth". After we process it, information can be painted with truth or falsehood depending on our knowledge or intentions.

I am not sure if information is subject to entropy. Information is static. It is not an object. It is just a record of what has happened. The object phenomena may be subject to entropy, but the information about the phenomena is not.

Those are my two cents from one non-expert layman.

[pjknibbs]

Information requires consciousness (an observer) and sense perception.

I disagree. Information can exist if there is no-one to observe it, e.g. in the hard disk of a computer that's switched off. The act of observing is merely one method of *processing* that information.

[Gavrushka]

Information I see as data in a comprehensible format. As that's subjective, it suggests 'information' is a conversation between 'it' and the observer.

And with that established, I have to say RM's opening post was not information to me, but it did inspire a brain-spasm, a nosebleed and double glazed eyes.

I get pjknibbs post, but I think the raw data on a hard disk contains the potential to be information, but only when interpreted.

[RegisterMe]

The gold plaques on the two Voyager craft, that will likely outlast the lifespan of our species, and will likely never be observed in any way, by any other sentient being, contain information, no?

What about a hydrogen atom slipping over the event horizon?

[Alan Phipps]

Information is incoming data that you decide is useful, relevant and/or of interest to you, or that you may wish to store as it might become useful etc in the future. Information is refined rather than created by further collating and processing of the received data. Incoming data which does not meet the previous criteria is effectively 'noise' and is often immediately disposed of, ignored or forgotten.

Of course you can also decide that incoming data may become information for some other party and so store it away for their benefit.

[Gavrushka]

The gold plaques on the two Voyager craft, that will likely outlast the lifespan of our species, and will likely never be observed in any way, by any other sentient being, contain information, no?

What about a hydrogen atom slipping over the event horizon?

Well, they have the potential to be information, but who are they informing if not observed? It simply depends on how you define it. - So I'd say it's not a voice unless an ear hears it.

If there is a definitive 2019 definition of information, one that all recognised sources agree upon, I'd love to see it posted.

[Vertigo 7]

The gold plaques on the two Voyager craft, that will likely outlast the lifespan of our species, and will likely never be observed in any way, by any other sentient being, contain information, no?

What about a hydrogen atom slipping over the event horizon?

Well, they have the potential to be information, but who are they informing if not observed? It simply depends on how you define it. - So I'd say it's not a voice unless an ear hears it.

If there is a definitive 2019 definition of information, one that all recognised sources agree upon, I'd love to see it posted.

I would say that they CAN inform, not have to. Like that old saying, "If a tree falls in the woods and no one is around to hear it, does it make a sound?" As science has proven, sound permeates through solids, liquids, and gas, so unless the woods are in a vacuum, yes it does make a sound =p

[Gavrushka]

LOL, Vertigo, you git!

[Observe]

Information requires consciousness (an observer) and sense perception.

I disagree. Information can exist if there is no-one to observe it, e.g. in the hard disk of a computer that's switched off. The act of observing is merely one method of *processing* that information.

Perhaps it would be useful if we define the word information.

- knowledge communicated or received
- knowledge gained through study
- the act of informing
- from Old French informacion "advice, instruction"
- from Latin infromationem "outline, concept, idea

The computer hard disk is the same as a flower. There is potential information, but until we study the flower, we have no information about it. If we see a red rose, we now have information that the rose is red or smell it's fragrance etc. Until we observe the rose with one of our senses, there is no information about it. Until we decipher the data on a disk, it is just a collection of atoms.

We don't have knowledge about the status of Schrodinger's cat until we gather information regarding it. The information gathering, must involve a conscious observer. Even if we have a digital camera automatically dumping data to a disk, we can't proclaim it as information until we take a look at it.

We can infer information about something that we don't directly observe. We infer that the tree does make a sound when it falls in the forest with no one is around to hear it. In this case, our sense of thought informs us based on our knowledge of physics.

[red assassin]

Information has a very boring physical definition, which amounts to "the values necessary to describe the state of a system". If that system is an electron, for example, the information it carries is the parameters of its wavefunction. If that system is your hard disk, the information is the bit state of every bit in your hard disk.

Compressability matters, and so information is the same thing as entropy. If you have ten thousand quantum objects which can be in one of two states, the entropy/information content is a lot lower if they're all in the same state than if they 're randomly allocated, which you can see if you try and communicate them: in the same state I just need to say "0-9999 are all in state 0", whereas if they're randomly allocated with equal probability I need to list them each individually: "0, 1, 1, 1, 0, ...."

(Today's SMBC is very relevant to this discussion: https://www.smbc-comics.com/comic/entropy)


Of course, any other definition of information ultimately reduces to the parameters of the state vector for the atoms making up the storage medium for said information, whether those are you hard disk, a Voyager plaque or your brain, so we shouldn't need to discuss this any further.

[fiksal]

We should indeed separate physical terms from not


Information is an abstract concept that we assign.

It can be recorded via various physical means.


Entropy wise, any such organized structure can decay.

[euclid]

An interesting question, RegisterMe, and not trivial to answer. Just one of many aspects is descibed in the novel "His Master's Voice" by Stanisław Lem.

Cheers Euclid

[Star_Raider15]

If you ask me, this becomes even more complicated when you take into account there's a law in physics that says information is never actually lost, even if it enters into a black hole. You can read more about that one here: https://en.wikipedia.org/wiki/No-hiding_theorem

I'm still trying to wrap my head around that problem, but quantum physics is pretty mind boggling.

If you're looking for a more philosophical approach regarding information, I've found this short article to be pretty neat: https://hastyreader.com/the-only-thing- ... w-nothing/

[Bishop149]

Information has a very boring physical definition, which amounts to "the values necessary to describe the state of a system". If that system is an electron, for example, the information it carries is the parameters of its wavefunction. If that system is your hard disk, the information is the bit state of every bit in your hard disk.

What about the light speed barrier in the context of this question?
As I understand it "Nothing can travel faster than light" is not actually correct, more accurate would be "Information can not be transmitted faster than light". In layman's terms whilst you might find some clever work around to move something faster than light it could have no "practical" purpose because anything "practical" hinges on information of some kind. . . a message, a physical structure etc.

I terms of the definition you provided is the "state of the system" in question the point of origin of your wormhole?

[red assassin]

What about the light speed barrier in the context of this question?
As I understand it "Nothing can travel faster than light" is not actually correct, more accurate would be "Information can not be transmitted faster than light". In layman's terms whilst you might find some clever work around to move something faster than light it could have no "practical" purpose because anything "practical" hinges on information of some kind. . . a message, a physical structure etc.

I terms of the definition you provided is the "state of the system" in question the point of origin of your wormhole?

It's easy to construct systems where "something" travels faster than c. For example, one can construct electromagnetic radiation where the phase velocity is greater than c. Or in entangled particles, when a measurement is made on one particle, it affects measurements made to the other particle immediately, regardless of distance. But yes, you're correct, in no case does the thing travelling faster than c actually carry any information, so you can't do anything with it.

I'm not quite sure what you mean with your wormhole question, can you clarify?

[Bishop149]

I'm not quite sure what you mean with your wormhole question, can you clarify?

I was just using the wormhole as a quick, dirty (and probably entirely inaccurate) metaphor for FLT transit

You have the local environment at the entrance of the wormhole and from this environment a particle enters the "wormhole" passing through it faster than light (would be able to travel in non-distorted space time) to arrive at the exit.
Now you can observe the particle leaving the exit and from this you can obviously determine some information, at the very least that observation itself.
Am I right in thinking that the information you can NEVER get from such observations is anything relating to the that local environment at the entrance?
But what about incredibly basic stuff? Say the particle was a hydrogen atom, couldn't you at the very least infer "There is some hydrogen near the entrance!"

[pjknibbs]

The problem with any form of FTL is that you always end up with some frame of reference where an effect predates its cause, which is a fairly fundamental principle of physics.

[red assassin]

Yeah, pjk is right. Fundamentally you can't construct any sort of object or device which is analogous to your wormhole in that it moves something which carries information from A to B faster than c, and by definition moving an atom around carries information. Any approach that would let you do this leads to violations of causality. General relativity would have to be very significantly wrong in order for this sort of thing to be allowed.

There are generally more specific reasons that any given idea for an FTL communications system won't work, but "if you can violate causality with it it's probably not a realistic idea" is a handy rule of thumb. For quantum mechanics in particular, for example, see the no-communication theorem.