But 1) that is an estimate of human brain computing power, based on number of neurons and possible connections. We have no idea if that is really a valid unit of computing "power." Do brain only compute things via voltage thresholds across synapses? Then yes, maybe this is an accurate estimate. But there are a whole lot of subcellular signal cascades happening at molecular levels we can't even begin to count and we have no idea whether or not those are also computing something accessible to the rest of the brain. 2) Matching the computing power of a brain doesn't mean you can emulate it. Emulating something requires knowing the target architecture and software. It is possible we can figure out exactly what a brain is doing to an accurate enough level to emulate it by the end of the century, but we certainly don't know how to do that right now, even if we had the computing power. Remote imaging techniques are not nearly good enough (because again, so many of the processes are subcellular) and you can't open up a brain without destroying it. This is actually a much broader problem in biology and we have figured out ways to partially dissect some animals while still keeping them alive long enough to figure out how a system works in vivo, but doing that with a brain is not something we have ever come remotely close to doing and there isn't really any ethical way to even think of how we can try to figure it out.
The human brain works, therefore this technique will work, it's just a matter of having enough computing power.
I will re-iterate though, we are pursuing various alternative pathways to artificial intelligence, and modern machine learning has already demonstrated super-human performance within constrained domains. It's my personal belief that we will achieve human-level general intelligence long before WBE becomes practical.
I don't believe there is anything guaranteed about "whole [human] brain emulation" in this century.
[1] This isn't quite true, because we estimate there are around 10^22 to 10^24 stars in the universe, while estimations for number of synapses range from 10^14 to 10^15.
It's not impossible that some sort of thing would happen, but anyone who tells you that it can't possibly fail to be achieved in the next 80 years is lying, either to your or to themselves.
There is a certain # of calculations/s necessary to meaningfully emulate a neuron. We currently have no idea what level of fidelity is required, but we can make guesses for each of the levels of fidelity that might be required.
The estimates that assume the highest (and likely unnecessary) level of fidelity currently top out at 2100.
For the record, I never claimed that failure was impossible, I used the phrase "on track". It's totally possible that there might be some surprise quantum weirdness going on that would be intractable to emulate with classical computers, but we've found no evidence of that to date.
Let that sink in. We know it isn’t impossible to run a general intelligence computer on 20W because every single one of us is living proof that it is possible. There is no reason why something man made shouldn’t be able to do the same thing. How to do that is of course a different matter, but it isn’t speculative that it can be done, it’s a direct consequence of our own existence.
Is this actually true? I haven't heard of this. You're saying we will have an AI as good as a grown educated adult before 2100? I can't believe this at all - do you have a citation?