> First, a fusor is a bench-top nuclear fusion device. The main downside is that no one has figured out how to get more useful energy out of it then we put in. So probably not what you had in mind.
> Of course, it's also a completely ridiculous design that approximately no-one would want to use in practice. Especially when you already have more conventional nuclear fission reactors.
Right, and that's the point.
There are three logical leaps here, and proof is missing for all three.
- One, that AGI is something we can replicate in a Turing Machine.
AGI might require a specific effect in quantum mechanics to work, for example. Light refraction is completely understood, but still extremely difficult to solve for a single case -- computing power is getting there, but it took about 60 years from it being understood to us being able to compute it reasonably, and even then it's only an approximation -- our best rendering farms about around 5 F-stops. That's nowhere near the human eye's ability.
Another example, the 3-Body problem solved for N-bodies. Or how about, protein folding. Folding@Home is remarkable, but even with the combined GPUs of hundreds of volunteers, it still takes Folding@Home months, years, to calculate the folds of a single protein. The brain has billions of them.
- Two, that we will figure out the solution to Turning Machine simulation in our lifetime.
This can stand on the arguments of one. I'd just like to add that there are many really simple conjectures that are as-yet unsolved within mathematics. The Collatz conjecture is a good example here, but there are hundreds of thousands of others. Despite it being probably the simplest problem to teach, it's been about 90 years and even proof theory machines haven't made too much headway. Erdos, probably the greatest mathematician to ever have lived, stated "Mathematics may not be ready for such a problem". In that, subject experts doubt our ability to solve it within our lifetime.
Why should this be any different for an exponentially harder problem?
Perhaps a reference to the fact that it took about 150 years to go between "neurons are in the brain and influence our actions" to "we can do brain surgery, kind of...". And probably about 200 more years until we can say we actually "understand" the brain in a meaningful way?
- Three. That the resulting device will be practical, useful, and will be able to understand itself enough to replicate a better version of itself, within a reasonable timeframe.
I think you argued this sufficiently yourself! The fact that we can build something doesn't give it use. We can build machines that extract energy off of graphene. At no point does it make it useful to do so, however.
And yet, despite all of these unsolved problems, we are supposed to be able to simulate a machine to replicate the brain? In the next 20 years, no less?! Is it not unreasonable to think that this is a preposterous assertion whatever dimension you look at it through? That so many people have thrown themselves into wishful thinking, and cults at that, is beyond me.