Two major challenges technology has been tackling: 1. Immortality and eternal life Especially for the wealthy and powerful, everyone hopes to live forever. In recent years, breakthroughs in organ replacement technology and cellular reprogramming clinical trials have significantly extended human lifespans, but we're still far from achieving immortality. 2. Time travel, going back to the past Everyone wishes they could go back to the past to fix regrets, change the future, and make the present better—like buying 100 $BTC in 2010.