For decades, fusion energy has sat at the edge of humanity’s clean-energy imagination – a promise of virtually limitless power that always seems just out of reach. But for Xie Huasheng, a fusion theorist and plasma simulation scientist, the industry finally has a tangible way to shorten its costly trial-and-error cycle: better software.“Fusion simulation software has long faced an ‘impossible triangle’,” Xie said. Existing tools, he argued, tend to be either accurate but computationally...