There's a 50% chance AI machines will accomplish virtually every task better and more cheaply than human workers in the next 45 years, and once that is achieved, AI systems will rapidly become superior to humans, according to a new study conducted by researchers at Oxford and Yale.

Timeline of advancement: The research shows that there is a 50% chance AI will automate all human jobs in the next 122 years, but in certain tasks, humans will be outperformed much sooner:

AI will surpass humans in language translation by 2024, writing high-school essays by 2026, truck driving by 2027, retail work by 2031, writing a bestselling book by 2049, and working as a surgeon by 2053, the research said.

The bottom line: Researchers believe that acceleration of high-level machine intelligence (HLMI) will happen in less than 50 years, and bring with it potentially "catastrophic" risks for society that must be prepared for.

The potential risks: In addition to possible unemployment, the study notes that the transition to a world run by AI machines would bring new challenges, "such as rebuilding infrastructure, protecting vehicle cyber-security, and adapting laws and regulations."

The study's caveats: The researchers collected data from some 352 researchers who responded to their survey, and the predictions for how fast and how drastic an intelligence explosion would arise varied by geographic region. For example, the study notes that Asian respondents expected HLMI in 30 years, while North American researchers pegged it at 74 years.