The 22nd century
The widespread emergence of post-scarcity and resource-based economies, rapid growth of transhumanism, and major developments in space travel all mark the 22nd century. Practically all of the world's energy comes from either fusion or renewable sources now.
Artificial intelligence – having begun to merge with human intelligence in the previous century – now surpasses it, reaching whole new levels of cognitive and intellectual capability. Though lacking the raw emotions and subtle traits of organic human minds, the sheer speed and power of AI begins to profoundly alter the course of history. Almost every high-level decision by government and business now comes directly from these sentient machines, which oversee vast swathes of virtual employees, robots and other automated systems.
Developments in space during this time include numerous permanent, manned settlements on the Moon and Mars; regular crewed trips to the gas giants; huge mining operations in the asteroid fields; and various interstellar probes. Space tourism booms during this period and trips to the Moon's surface and elsewhere become relatively commonplace.
The speed and magnitude of progress now occurring, both on Earth and throughout the Solar System, is creating what earlier forecasters would have named a technological singularity. Indeed, many of the scientific discoveries in the 22nd century exceed the comprehension of "natural" unaided humans lacking the requisite brain upgrades and enhancements. The most notable breakthroughs are those in quantum physics – but wholly new fields also emerge that were untapped in the previous century.