> given that we don't yet have a mathematical model of all of physics as we know it
Yes... but that's in the area of the big bang and black holes. My understanding is that the chemistry of the brain is very well modeled.
So, unless we find unknown physics, and unless that physics behaves differently than every other known physics, humans are computable?
Do I have that right?
Let me illustrate with an example. Are you familiar with with the Collatz conjecture? It's an example of a system with only one variable, and two simple rules. Are you certain that there exists a computer program that in finite time can compute where any given integer ends up?
Now consider throwing a ball in the air. Can you even write down the rules that each of the ball's subatomic particles obeys? How can you be certain there exists a computer program that in finite time can predict where any of the particles, for any ball, ends up?
> the chemistry of the brain is very well modeled
There are models, but the fact of those models is that they do not apply to "any degree of accuracy", as you claim.
Consider the ball thrown in the air again. Is the ball affected by what happened 100 years ago, inside of a black hole 100 light years away? Why would it not be affected by that? Or if you grant that it is affected by that, do we then need a model to predict those effects before we can "evaluate" them?
EDIT regarding the below linked blog post: Did you read the rest of my comment? Did you even read the blog post you linked to?
> We certainly don’t have anything close to a complete understanding of how the basic laws actually play out in the real world — we don’t understand high-temperature superconductivity, or for that matter human consciousness
Can you try to consider my central point before replying: Are the rules governing physical reality simpler or more complex than the Collatz conjecture? Does there exist a (theoretical) computer that can "evaluate the Collatz conjecture to any degree of accuracy"?
EDIT 2: I'm not the one moving goalposts. On what grounds are you classifying the question whether a given number ends at 1 or not for the Collaz conjecture as an "inifite" computation? It's a simple boolean question, yes or no. All you have to do is build a computer that can answer yes or no for each integer. Isn't that simpler than answering the position of each atom in the ball after the throw? Each is just a function, what makes one more infinite than the other?
Also, regarding determinism, just read this article by the same guy you linked: https://preposterousuniverse.com/blog/2011/12/05/on-determin...
> For everyday-life purposes, we can’t get around the fact that quantum mechanics makes it impossible to predict the future robustly.
> There are models, but the fact of those models is that they do not apply to "any degree of accuracy", as you claim.
Are you sure?
https://preposterousuniverse.com/blog/2010/09/23/the-laws-un...
Friend, I'm not going to chase your ever changing text. Please just use the reply button.
> For everyday-life purposes, we can’t get around the fact that quantum mechanics makes it impossible to predict the future robustly.
You've moved the goalposts again. I said simulate, not predict. It is possible to simulate the entire Schrödinger wavefunction.
And PLEASE - just use the reply button. It is impossible to track every time you edit your comment.
PLEASE just stop complaining about "moving the goalposts" when the issue is your own lack of clarity of both expression and reasoning. WHAT is the distinction between "simulate" and "predict"? You said neither by the way, you said "evaluate".
> ANY physical system can be evaluated to ANY DEGREE of accuracy by a computer
It's completely SENSELESS to claim that they are distinct, because in order to EVALUATE or SIMULATE the physical system you will need a FUNCTION which COMPUTES the STATE of the system at a given point in time. The only POSSIBLE distinction between SIMULATING and PREDICTING would be the time taken for the computation, but that is COMPLETELY IRRELEVANT as long as it is finite.
Again, your own source says:
> We CERTAINLY don’t have ANYTHING CLOSE to a complete UNDERSTANDING of how the basic laws actually play out in the real world
How does that square with your claim above?
> You said neither by the way, you said "evaluate".
You are entirely correct. I was sloppy in my first comment. I should have said simulate. My sincere apologies if that's been the crux of our dispute.
> The only POSSIBLE distinction between SIMULATING and PREDICTING would be the time taken for the computation
No. The distinction is in determining which "you" is you. When simulating the wavefunction, every you is simulated.
> We CERTAINLY don’t have ANYTHING CLOSE to a complete UNDERSTANDING of how the basic laws actually play out in the real world
It's very understandable if you include his following sentence:
> But these are manifestations of the underlying laws, not signs that our understanding of the laws are incomplete
He's saying we don't understand emergent behavior produced by the laws - not that the laws themselves are incomplete. E.g. we don't know how/why a bag of neurons turns into a person.
Re: Collatz - you've moved the goalposts. Answering Collatz requires solving a halting problem. I didn't claim that I could find the end of an infinite computation. I claimed to be able to simulate a finite one.
And - you should reply to my comments rather than edit your old ones.