A primordial black hole in a fifth dimension may explain a record-breaking neutrino

Scientific American reports that a new paper proposes an exploding primordial black hole as the source of a neutrino detected off Sicily in 2023. The black hole may have formed from cosmic strings and sat inside a fifth dimension, which a coauthor says could explain why no photons accompanied the detection. Other scientists say the evidence is tenuous and point to possible sources such as high-energy cosmic rays or blazars.