Deep sleep doesn’t cut us off from the outside world as much as scientists had thought. Plus, the Greenland ice sheet can be saved if we claw back global temperatures and meet the unsung scientists behind Nobel-prizewinning quantum dots. Deep sleep doesn’t cut us off from the outside world as much as scientists had thought. Plus, the Greenland ice sheet can be saved if we claw back global temperatures and meet the unsung scientists behind Nobel-prizewinning quantum dots.