We have a guest on the show today - Ben Franta. Ben is a scientist, science historian, science writer, and activist. He studied for a PhD at Harvard working on solar cells; while he was at Harvard, he became involved in the movement to persuade that University to divest from fossil fuels. After finishing his first PhD, he moved to Stanford to take up a PhD in the History of Science, where he now studies the history of climate politics, and the influence of fossil fuel companies on that politics. His recent article in the Guardian, published on New Year's Day, explained how Edward Teller knew about global warming in 1959 and warned the fossil fuel industry - thirty years before it hit the mainstream. The second half, which you're about to hear, is mostly about climate change activism: what can we do to most effectively deal with climate change? If you enjoyed what our guest had to say, you can find his work via his LinkedIn "Benjamin Franta": https://www.linkedin.com/in/benjaminfranta/ and follow him on Twitter @BenFranta. The article that Ben referred to, which details the case for climate activism, was written by Geoffrey Supran and Ploy Achakulwisut; it's on Mashable, and it's called "How You Can Fight Climate Change."  https://mashable.com/2017/05/06/how-you-can-fight-climate-change/ As always, you can follow us on Twitter @physicspod, and go to our website at physicspodcast.com, where you'll find a donate link that will help you support the show if you're so inclined. Until next time.