NASH_LETTERS1.PDF

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DEPARTMENT OF M ATHEMATICS 
MASSAC 
' 
HU SETTS INSTITUTE 0 
CAMBRIDGE 
F TECHNOLOGY 
39, MASS. 

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MASSACHUSETTS INSTITUT·E OF TECHNOLOGY 
CAMBRIDGE 39, MASS. 
J 
DEPARTMENT OF MATHEMATICS 

The &s devote th keyr Coantainin ¢ brts of ome! oe nm tS FT MarimvMn_ sha rhe prmeess tf on ane jy Ul Si meee swell Cn i CONS | the. ce : . iis suet: to bemg brkey we, chovld, assure Hat ee Hwmes the Ley heiy Knows ory ing. bt the ke Used, and, i+ we. Cee rhe key prea this mlocmation . We see jmnmed.tactely that— BH IN principle. the enen yeeds ittle mberrwaha to begin TO Veoy | jock. de dovwy.— the. process . Esseitha//, aS Soom 4s 5 i bits of Aicip ME Sse apne hon fous mitbed— the, ae [§ es detemined, « This Is no secusit On A prachca| ke should vot fos long . But phig oF bog aise consid oe …

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pn MOST ks: os ars AG IV Cob see . 7 meet 1“ as Ni oy peel st “All thereby ah eames Pipher, 2 - where He gs aptly Jeet portioas ot the ra pect COM plexly with each other on the Voqomuaetot sheit u | fimeafe effets the opp enciphemg , TF the Ss, re Cowpl lown— mcweas eS oe ire de AP the Fe pee in ots with. rte cose st S! hae wk TAIS <a Con jecture , assum tout Is 2457 +e ap % ai ! anor it Is gps foas ible to design. ach irre os eHectvel on breakable : cipny more. S$ aes i  aghe freokmg shake shold. becanre & 1 Se ferns , A ete.

| The hotupe of this conjecture 1S is Such Hur L prs pate “arte fox acpecal type phe, Now do L expect it fo be prover. Bot nis does not destoy its sign ifance_, The. pro bebilrty sh the tsvth Sh te cm jecture p~ be. guessed at ate hese oF experience, wit cipher, aid dedphs mf LF palihed- opi img Mceline +6 hejieve m de entia|/ com pecfture the Fo thnk we Ge US.) cor “not afbed. wt +0 wake vse iis rr. Also we haul Hy te keepe toack fF tle pm Z. ess sk Foes nations pfowords imbeeatable’” wypes oF ciphacs. Since the U.S. presumably does ys Wark ote nations fo use “eiphes we Gunot expect te break …