Where has today's AI passed humans, and where has it not? Math olympiads, programming, drone racing, driving, professional work, spatial reasoning and robot hands, sorted using figures from papers and primary announcements. Also: learning from little experience (ARC-AGI-3), self-improvement, and three walls that remain in the physical world. Part 2 of Is There an Upper Limit to AI Intelligence?
If an AI keeps improving itself, how far can its intelligence go? Five questions on the physical limits of computation (about 5.4×10^50 operations per second per kilogram, 10^120 over the history of the universe), on when self-improvement levels off, and on how the compute behind the September 2026 Navier–Stokes result compares. Part 1 of 2.
In 1935 the EPR paper asked whether quantum mechanics is complete, Bohr answered under the same title, and Schrödinger left behind a cat and the word entanglement. What the cat was meant to show, how Bell turned the question into an experiment in 1964, and what the loophole-free tests of 2015 settled and did not. The final part of the series The Rise of Quantum Mechanics.
At the Solvay conferences of 1927 and 1930 Einstein pressed Bohr with thought experiments, and Bohr defended the uncertainty relation. But the proceedings and letters of the time show Einstein asking something else: is the theory complete, and what happens between distant places? The movable screen, the box of light, and the question left open. Part 5 of the series The Rise of Quantum Mechanics.
In 1928 Bloch showed that an electron wave passes through a perfectly regular crystal without bumping into anything. That made insulators the puzzle. From Wilson's 1931 answer (it is how full the bands are) to a time when silicon was filed under metals, and to the solids the theory could not reach. Part 4 of the series The Rise of Quantum Mechanics.
In 1928 Dirac wrote an equation that made quantum mechanics agree with relativity. Spin came out for free — and so did unwanted answers with negative energy. From the full house and its empty seat, through the proton mix-up and the anti-electron, to the positron Anderson found in a cloud chamber in 1932. Part 3 of the series The Rise of Quantum Mechanics.