Our two covers this week are the yin and yang of technological progress. Both AI-powered war and solar energy are being transformed by the head-spinning, pundit-confounding reality of exponential growth. When something doubles and doubles again, our brains find it hard to comprehend. It suddenly emerges from the background and becomes world-changing. Even as you try to catch up, it accelerates away from you.

We have reached that point with the technologies behind both our cover stories. When solar power was a tenth of its current size a decade ago, it was still seen as marginal, even by experts who knew how fast it had grown. Consider that the next ten-fold increase, over the next decade, will be equivalent to multiplying the world’s entire fleet of nuclear reactors by eight in less than the time it typically takes to build just a single one of them. Then imagine what will happen in the decade after that.