Not doubting you, but why do you think this is so unbelievable? It seems intuitive to me that tracking CO2 levels in a shared space would act as a proxy for tra

Not doubting you, but why do you think this is so unbelievable? It seems intuitive to me that tracking CO2 levels in a shared space would act as a proxy for tracking how much of other people's breath you are breathing in. Some quick googling suggests this is a real effect. https://www.sciencedaily.com/releases/2021/04/210407143809.htm https://www.sciencedaily.com/releases/2021/04/210407143809.h...