Covalent/metallic vs ionic bonds implements the high energy density vs wetware constrained distinction I was referring to, so we are mostly in agreement; that is my paradigm. But the evidence is pretty clear that “ionic bond and protein” tech does approach the Landauer limit—at least for protein computation. As for the brain, end of Moore’s Law high end chip research is very much neuromorphic (memristor crossbars, etc), and some designs do claim perhaps 10x or so greater synop/J than the brain (roughly), but they aren’t built yet. So if you had wider uncertainty in your claim, with most mass in the region of the brain being 1 to 3 OOMs from the limit, I probably wouldn’t have commented, but for me that one claim distracted from your larger valid points.
Covalent/metallic vs ionic bonds implements the high energy density vs wetware constrained distinction I was referring to, so we are mostly in agreement; that is my paradigm. But the evidence is pretty clear that “ionic bond and protein” tech does approach the Landauer limit—at least for protein computation. As for the brain, end of Moore’s Law high end chip research is very much neuromorphic (memristor crossbars, etc), and some designs do claim perhaps 10x or so greater synop/J than the brain (roughly), but they aren’t built yet. So if you had wider uncertainty in your claim, with most mass in the region of the brain being 1 to 3 OOMs from the limit, I probably wouldn’t have commented, but for me that one claim distracted from your larger valid points.