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Is there a minimum size for an atomic bomb? Would it be possible to make a microscopic one that results in a very small explosion?

Simon McLeish
Lechlade, Gloucestershire, UK

Nuclear explosions are different from conventional explosions. A normal explosive substance uses an external detonating trigger, and smaller quantities of explosive cause smaller explosions (from bombs akin to those used in the second world war, which destroyed buildings, to the cap in a toy pistol). A nuclear bomb doesn’t work like that – at least, not a fission bomb such as the ones set off in Hiroshima and Nagasaki.

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