2026.06.10 – Dr Karl Kruszelnicki – Wednesday’s with Dr Karl

1) Restaurant Problem, Feynman At a restaurant that you go to regularly, should you (A) stick to your favourite dishes that you know and love or (B) try new dishes in the hope of great and unexpected culinary delights? 2) The Lymphatic System – still largely unknown. The lymphatic system is a network spanning the entire body, consisting largely of thread-like vessels and bean-shaped nodes. Despite having been described in the first known medical scientific paper, the lymphatic system remained a mystery for millennia afterwards. Being extremely elusive and incredibly delicate, it is hard to study – the ruby-red blood system, in contrast, got far more attention. Lymphatic vessels permeate nearly every organ of our body. Only in recent decades have researchers begun to appreciate the profound role the system plays in health and illness, thanks to advances in imaging techniques and molecular beacons that shine a light on its inner workings. We are getting closer to harnessing the powerful roles of lymphatics in keeping us healthy. 3) GeoEngineering, to reduce effects of Climate Change Humanity will attempt large-scale efforts to block radiation from the sun before the end of the century, according to leading climate scientists surveyed by New Scientist, in a last-ditch bid to shield Earth’s inhabitants from the worsening impacts of climate change. Two-thirds of respondents believe we will see risky interventions to tweak the atmosphere before 2100. Worryingly, 52 per cent say this will probably be driven by a “rogue actor” – such as a private company, billionaire or nation state – highlighting widespread concern that the world is moving closer to attempting such climate-cooling interventions without any global process in place to manage decision-making or mitigate the serious risks that deployment brings.