Today on Trust Me, I’m An Expert, we’re bringing you the explainer episode - where we ask researchers to unpack some truly tricky topics.

The University of Queensland’s James Sherlock explains what psychology can reveal about why people like pimple popping and ingrown hair removal videos. They’re more popular online than you may realise, as a quick YouTube search for words like “pimple” or “blackhead” will attest - but be careful, they’re not for the faint of heart.

And by the time you’ve finished this episode, you’ll be able to explain quantum mechanics in a nutshell - how it affects everything from the way your jeans are cut to the headphones you’re using to hear this podcast.

Andrew White, a professor in physics at the University of Queensland, gives us a great little primer on how far quantum mechanics has come, why the research hit a wall, and what exciting breakthroughs might be just around the corner.

But first, we’ll hear from Raffaello Pantucci, a King’s College London expert on lone actor terrorism. He talks about what the research says about this troubling phenomenon, and why police never use the phrase “lone wolf” to describe it.

Trust Me, I’m An Expert, out at the start of every month, is a podcast from The Conversation, where we bring you stories, ideas and insights from the world of academic research. Find us and subscribe in Apple Podcasts, Pocket Casts or wherever you get your podcasts.

And lastly, if you like this podcast and want to help keep it on air, please consider making a contribution during our two-week donations campaign.

Kindergarten by Unkle Ho, from Elefant Traks

Hip Horns With Drums by (none given), from Free Music Archive

Somnolence by Kai Engel, from Free Music Archive

Heaven Beyond the Trees by Squire Tuck, Free Music Archive

La tapa del domingo by Circus Marcus, from Free Music Archive

PIMPLE/BLACKHEAD POPPING: REACTION WARNING, Day with James, YouTube.

CNN - The challenges of lone-wolf terrorists

Vignesh Ram - World mourns following Norway tragedy

BBC - Broadcast from Westminster terror attack

ABC News - Sept 20, 2001 - Bush declares war on terror

ABC News (via Fairfax) - Malcolm Turnbull press conference on the threat of lone-actor terror