A leading Italian physicist has clapped back at online trolls who made sexist remarks after she shared a video of herself wearing a low-cut dress.

Nuclear scientist and quantum mechanics expert Gabriella Greison, 51, posted a clip to her Instagram account as she prepared to travel for an academic event in Sicily.

The scientist, who is based in Milan, was shown wearing a pale green dress with a low-cut neckline as she told her followers that she was going to be a guest of honour at a graduation ceremony in the University of Messina.

But Greison's video, which has racked up thousands of views, drew sexist reactions as followers commented on her revealing outfit.

'Indecent clothing, vulgar, undignified,' one critic wrote.