Weekly: Does loneliness really cause ill health?; A time-travelling photon; The supermassive mystery of early black holes

Episode 268 Research has long linked loneliness to surprising health conditions, including diabetes and some cancers. The assumption has been that loneliness in some way causes these issues, perhaps through increased stress or inflammation. But in a study of tens of thousands of people’s biomedical data, that link has gotten more complicated. Where does this leave the relationship between loneliness and health, and the public health programs that are trying to tackle both? Supermassive black holes are so big and existed so early in the universe’s history that astronomers are unsure how they formed. Dark matter to the rescue? Among the theories of how they formed is “direct collapse,” which a study finds may be possible with some help from decaying dark matter. But a specific type of dark matter is needed to make this theory work…so what’s next? A photon has been observed travelling in negative time. It was caught leaving a cloud of atoms before it ever entered it. How is this possible? Is this a time travelling photon? Well, somehow, no laws of physics were broken. Obviously some quirky quantum effects are in play – but what exactly is going on? Plus: How Earth may have once had a ring around it; a pair of black hole jets that are 23 million light years across; how some long-stemmed flowers have evolved to help bats pollinate them; and the discovery of a brand new, teeny tiny chameleon. Hosts Timothy Revell and Christie Taylor discuss with guests Leah Crane, Sophie Bushwick and Karmela Padavic-Callaghan. To read more about these stories, visit newscientist.com. Get 10 weeks of unlimited digital access to newscientist.com and our app for £10/$10 by visiting: https://www.newscientist.com/podcast  Hosted on Acast. See acast.com/privacy for more information. Learn more about your ad choices. Visit megaphone.fm/adchoices