 
 <prompt> Wetin cause Von Neumann to face opposition from im colleagues sake of im ideas. Given di last question, write one context wey contain di answer. E fit be 1 - 20 sentences. Context: <response>: Von Neumann major contribution to di atomic bomb na for di concept and design of di explosive lenses wey dem need to compress di plutonium core of di Fat Man weapon wey dem later drop for Nagasaki. While von Neumann no originate di "implosion" concept, e bin one of di people wey dey push am well well, dey encourage di development against di instincts of many of im colleagues wey feel say such design no go work. E also later come up with di idea of using more powerful shaped charges and less fissionable material to greatly increase di speed of "assembly". 