RISK: What are the chances that a particle collider’s strangelets will destroy the Earth? “Johnson and Baram are concerned that these changes might increase the possibility that the collider will generate strangelets, hypothetical particles consisting of up, down, and strange quarks. Some hypotheses suggest that strangelet production could ignite a chain reaction converting everything into strange matter.” Leading to the Earth becoming “an inert hyperdense sphere about one hundred metres across.”