We have no idea how to estimate the computational capacity of the brain at the moment. We can make silly estimates like saying that 1 human neuron is equivalent

We have no idea how to estimate the computational capacity of the brain at the moment. We can make silly estimates like saying that 1 human neuron is equivalent to something in an artificial network. But this is definitely wrong, biological neurons are far more complex than this. The big problem is that we don't understand the locus of computation in the brain. What is the thing performing the meaningful unit of computation in a neuron? And what is a neuron really equivalent to? The ranges are massive. Some people say that computation is some high level property of the neuron as a whole, so they think each neuron is equivalent to just a few logic gates. These people would say that the brain has a capacity of about 1 petaFLOP/s. https://lips.cs.princeton.edu/what-is-the-computational-capacity-of-the-brain/ https://lips.cs.princeton.edu/what-is-the-computational-capa... Then there are people who think every Na, K, and Ca ion channel performs meaningful computation. They would say the brain has a capacity of 1 zettaFLOP/s. https://arxiv.org/pdf/2009.10615.pdf https://arxiv.org/pdf/2009.10615.pdf Then there are computational researchers who just want to approximate what a neuron does. Their results say that neurons are more like whole 4-8 layer artificial networks. This would place the brain well somewhere in the yottaFLOP/s range https://www.quantamagazine.org/how-computationally-complex-is-a-single-neuron-20210902/ https://www.quantamagazine.org/how-computationally-complex-i... And we're learning more about how complex neurons are all the time. No one thinks the picture above is accurate in any way. Then there are the extremists who think that there is something non-classical about our brains. That neurons individually or areas of the brain as a whole exploit some form of quantum computation. If they're right, we're not even remotely on the trajectory to matching brains, and very likely nothing we're doing today will ever pay off in that sense. Almost no one believes them. Let's say the brain is in the zettaFLOP/s range. That's 10^21 FLOP/s. Training GPT-3 took 10^23 FLOPS total over 34 days. 34 days has 2937600 seconds. 10^23/10^7 is about 10^16 FLOP/s. So by this back of the envelope computation the brain has about 4 orders of magnitude more capacity, or 1000x. This makes a lot of sense, they're using a pettaFLOP/s supercomputer basically which we already knew. We'll have zettaFLOP/s supercomputers soon, yottaFLOP/s, people are worried we're going to hit some fundamental physical limits before we get there. All of this is a simplification and there are problems with every one of these estimates. But, in some sense none of it means anything at all. You can have an extremely efficient algorithm that runs 1 million times faster than an extremely inefficient algorithm. Machines and brains do not run the same "software", the same algorithms. So comparing their hardware directly doesn't say anything at all.