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Information Is Physics

cacm.acm.org

31–40 of 78 posts

Re: Information Is Physics

#31
post #18

Earlier quoted context omitted.

I agree with you that humans are very different from optimization machines in that they have some freedom in what they choose to optimize. Alan Newell made this point a long time ago, back then attempts were made to describe humans in terms of control theory. It works up to a point, but autonomous behavior needs the faculty to set goals independently of pre-programmed optimization points as well as current situationa…

The article is bad, but the point of silly analogies to various technologies remains. Regarding the questions you addressed, my suspicion is that the brain's primary trick is to model the organism and the environment. Planning ahead, reasoning and synthesizing knowledge can all happen if you can do that. I'd argue (and of course I'm biased) that control theory is probably a better place to start thinking about the br…

Information processing as basis for human existence is not an analogy once you accept a very basic premise of what information is. It is the literal description of what is going on, even on the biological level. I've mentioned DNA, the immune system is another example.

If you want to be successful in a complex world, survive, replicate, you will profite massively if you know what is going on around you better than that other thing that wants to eat you. If you can grasp the structure of the physical world and predict its changes, you will come out on top. Information processing is an evolutionary necessity, because we are grounded in a physical world. Information is the successful way to deal with the world, because it gives the organism a choice.

Control theory is great if you want to describe real valued in- and outputs and their relationship over time. Like throwing a ball. But at some point we need to become discreet and abstract the real valued domain of space and time into symbols.

Re: Information Is Physics

#33
post #9

Earlier quoted context omitted.

Thank you for this. I spend a non-trivial amount of time telling people working in AI and machine learning (which I also do) that the brain isn't some parameter optimization machine and that analogies from whatever technology or math people are excited about aren't very useful. I wish some neuroscience education and articles like these were some part of the ML canon.

I couldn't disagree with you more. The article referenced by GP mistakes the form for the function. Just because the computer uses different technology than human tissue, doesn't mean it isn't emulating the same ultimate processes that are happening in our bodies. And even if we don't have the correct algorithms in sight today, there is every reason to believe that whatever processes are occurring in our brains and b…

> Just because the computer uses different technology than human tissue, doesn't mean it isn't emulating the same ultimate processes that are happening in our bodies

BUT: at least I think we are far from it. Very far. In the sense that we don't need more computing power of the current approaches to get e.g. AGI, we need radically new ones. And I actually don't see why this would be opposed to more neuroscience education, instead of excitement for cool but still quite limited models, and why this would be pretending that there is some "special magical non-material aspect to our existence"

How much can you compress the essential structure and complexity of an intelligent brain? It is an open question, but if in the end you can not compress it "enough", it does not have much practical consequences of it being also theoretically a mathematical object. And on top of that: we already know how to make new ones...

Re: Information Is Physics

#34
Landauer's principle intuitively: the laws of physics are reversible, and therefore two distinct states (1 or 0) always map to two distinct states (1 or 0, evolved). So how can you erase a bit - take a 1 or 0 and map them to a 0? The answer is that you have to send the 0 or 1 to the environment i.e. map 1 or 0 to (system,environment) = (0,1) or (0,0) , which manifests as the dissipation of heat.

Re: Information Is Physics

#35
post #19

I think the next step for physics could be potentially in establishing the link between abstract information and what is perceived as "real matter".

See thermal physics, which combines statistical mechanics and thermodynamics:

https://en.wikipedia.org/wiki/Thermal_physics

For a computation focused example, see Schneier's essay on strength of a 256-bit symmetric cipher:

https://www.schneier.com/blog/archives/2009/09/the_doghouse_...

Edit for completeness: rest energy converts to mass as follows: E = m*c^2

Re: Information Is Physics

#36
post #19

I think the next step for physics could be potentially in establishing the link between abstract information and what is perceived as "real matter".

So a form of Platonic realism? The abstract stuff forms the structure of matter.

Re: Information Is Physics

#38

Earlier quoted context omitted.

See also: brain as hydraulics, brain as a system of cogs, brain as a computer.[1] [1] https://aeon.co/essays/your-brain-does-not-process-informati...

Argh, that article! Those are metaphors at some level of representation!!! You could argue in the same specious way that a computer is not a computer because it is really a bunch of atoms interacting via non deterministic quantum mechanical rules so it can't really implement deterministic algorithms and error free information storage. The three conditions stated in the article basically are the set up for reinforceme…

> You could argue in the same specious way that a computer is not a computer because it is really a bunch of atoms interacting via non deterministic quantum mechanical rules so it can't really implement deterministic algorithms and error free information storage.

Jaron Lanier argues that computers and computation are cultural. Why give them a special ontological status? Yeah, we can think of the universe as computational or informational. We can also think of it as mathematical, mental or just whatever physics posits (fields, strings, higher dimensions, etc). Whatever the case, when someone like the article in the OP states that reality is X, then an ontological claim is being made. Its metaphysics.

One could instead argue that the world just is itself, and anything we say about it is our human model or best approximation. Which would be a combination of realism (the world itself) and idealism (how we make sense of it). Then it's just a matter of not mistaking the map for the territory. Instead of saying that the brain or the universe is X, we say that X is our best current map for Y. We don't say that London is a map. That would be making a category error.

Re: Information Is Physics

#39
post #22

Earlier quoted context omitted.

See also: brain as hydraulics, brain as a system of cogs, brain as a computer.[1] [1] https://aeon.co/essays/your-brain-does-not-process-informati...

> But the IP metaphor is, after all, just another metaphor With no apologies to the UNIX metaphor of "everything is a file", my favorite starting point for [pretending at] explaining intelligence/understanding/recognition has long been "everything is a metaphor" ;)

Everything is a file if you are brave enough.
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