Self-driving cars

This was meant to be the decade of the self-driving car , as governments began permitting testing on public roads. But you can’t hang up your steering wheel just yet. Car firms and tech giants have found it tricky to make self-driving cars work, while a string of crashes has dented public confidence.

Head transplants

Surgeon Sergio Canavero spent much of this decade claiming he was ready to perform a human head transplant , replacing a recipient’s body with one from a donor, and had lined up willing patients. He was heavily criticised by bioethicists, and most experts doubt the procedure is possible.

Faster-than-light neutrinos

It would have been the find of the decade. In 2011, researchers claimed to have caught ghostly particles called neutrinos breaking the speed limit of the universe . Sadly, the reality was more mundane: a loose cable and other issues had caused a measurement error.

Lab-grown meat

The world’s first burger made from lab-grown cow cells was served to food critics in 2013, at a cost of $325,000. Since then, the price has dropped as firms rush to commercialise their products, but consumer interest is waning as plant-based meat alternatives become available.

Asteroid mining

Two US firms, Planetary Resources and Deep Space Industries, attempted to kick off a solar system gold rush at the start of this decade, while Luxembourg bet millions on the concept. All have quietly retreated as asteroid mining turned out to be a pie-in-the-sky idea.