A video has gone viral of Canadian prime minister Justin Trudeau showing off his geek side by nailing a reporter's question about quantum computing.
Speaking at the Perimeter Institute in Waterloo, Ontario, where he was making a funding announcement, Mr Trudeau dared reporters to ask him about how quantum computing works during a question period.
When a reporter obliged, Mr Trudeau, a former teacher, gave a detailed and elaborate mini-lesson on the difference between normal and quantum computing, drawing laughter and applause from an audience of some of Canada's brightest theoretical physicists.
"Regular computer bit is ether a one or a zero. On or off. A quantum state can be much more complex than that because, as we know, things can be both particle and waves at the same times and the uncertainty around quantum states allows us to encode more information into a much smaller computer.
"So that's what's exciting about quantum computing," he said as the audience again burst into applause.
"Don't get me going on this or we'll be here all day. Trust me."
Mr Trudeau was welcomed to the institute by British physicist Stephen Hawking via a recorded video.