W ash ak ie ▁County , ▁Wy oming ▁Category : 1 9 2 9 ▁establish ments ▁in ▁Wy oming <0x0A> </s> ▁The ▁Fr isch – Pe ier ls ▁memor and um ▁was ▁the ▁first ▁technical ▁ex position ▁of ▁a ▁practical ▁nuclear ▁weapon . ▁It ▁was ▁written ▁by ▁exp atri ate ▁German ▁phys ic ists ▁Otto ▁Fr isch ▁and ▁Rudolf ▁Pe ier ls ▁in ▁March ▁ 1 9 4 0 ▁while ▁they ▁were ▁both ▁working ▁for ▁Mark ▁O li ph ant ▁at ▁the ▁University ▁of ▁B irmingham ▁in ▁Britain ▁during ▁World ▁War ▁II . ▁ ▁The ▁memor and um ▁contained ▁the ▁first ▁calculations ▁about ▁the ▁size ▁of ▁the ▁critical ▁mass ▁of ▁f iss ile ▁material ▁needed ▁for ▁an ▁atomic ▁bomb . ▁It ▁revealed ▁for ▁the ▁first ▁time ▁that ▁the ▁amount ▁ ▁required ▁might ▁be ▁small ▁enough ▁to ▁incorpor ate ▁into ▁a ▁bomb ▁that ▁could ▁be ▁delivered ▁by ▁air . ▁It ▁also ▁anticip ated ▁the ▁strateg ic ▁and ▁moral ▁imp lications ▁of ▁nuclear ▁weapons . ▁ ▁It ▁helped ▁send ▁both ▁Britain ▁and ▁America ▁down ▁a ▁path ▁which ▁led ▁to ▁the ▁MA UD ▁Committee , ▁the ▁T ube ▁Al lo ys ▁project , ▁the ▁Manh attan ▁Project , ▁and ▁ultimately ▁the ▁atomic ▁bomb ings ▁of ▁H iro sh ima ▁and ▁Nag as aki . ▁ ▁Background ▁ ▁Rudolf ▁Pe ier ls ▁▁ ▁Rudolf ▁Pe ier ls ▁was ▁born ▁in ▁Berlin ▁in ▁ 1 9 0 7 . ▁He ▁studied ▁physics ▁at ▁the ▁University ▁of ▁Berlin , ▁at ▁the ▁University ▁of ▁Mun ich ▁under ▁Arnold ▁Sommer feld