{"id":1511,"date":"2018-10-10T19:05:55","date_gmt":"2018-10-10T16:05:55","guid":{"rendered":"http:\/\/www.akademikidea.org\/a-kitap\/?p=1511"},"modified":"2024-07-16T10:52:10","modified_gmt":"2024-07-16T07:52:10","slug":"manhattan-projesi-ve-monte-carlo","status":"publish","type":"post","link":"https:\/\/www.akademikidea.org\/a-kitap\/manhattan-projesi-ve-monte-carlo\/","title":{"rendered":"Monte Carlo Y\u00f6ntemlerin \u00d6z\u00fc"},"content":{"rendered":"<p>&nbsp;<\/p>\n<p id=\"yui_3_17_2_1_1539190980845_995\">Kumarhaneleri ile \u00fcnl\u00fc Monoca Prensli\u011fi\u2019nin bir kenti olan \u201cMonte Carlo\u201d, ilk kez 1940\u2019larda A.B.D.\u2019nin\u00a0 Los Alamos Laboratuar\u0131&#8217;nda atom bombas\u0131 \u00e7al\u0131\u015fmalar\u0131n\u0131n yap\u0131ld\u0131\u011f\u0131\u00a0 Manhattan Projesi&#8217;nde bir araya gelen\u00a0John von Neumann(1903-1957), Stanislav Ulam(1909-1986) ve Nicholas Constantine\u00a0Metropolis(1915-1999) gibi bilimciler taraf\u0131ndan, bir grup matematiksel y\u00f6ntemleri nitelendirmek i\u00e7in kullan\u0131ld\u0131. Bu y\u00f6ntemleri ayn\u0131 amaca y\u00f6nelik di\u011fer say\u0131sal y\u00f6ntemlerden ay\u0131ran temel \u00f6zellikleri, s\u00f6z konusu problemi\u00a0<i id=\"yui_3_17_2_1_1539190980845_996\">sanal bir rulet tekerle\u011fi<\/i>\u00a0ile oynanan bir t\u00fcr\u00a0 \u015fans oyununa d\u00f6n\u00fc\u015ft\u00fcrerek,\u00a0<i id=\"yui_3_17_2_1_1539190980845_997\">problemin yakla\u015f\u0131k \u00e7\u00f6z\u00fcmleri<\/i>ni \u00fcretmeleridir. Bu yakla\u015f\u0131k \u00e7\u00f6z\u00fcme,\u00a0 sanal rulet tekerle\u011finin \u00fcretti\u011fi\u00a0<i id=\"yui_3_17_2_1_1539190980845_998\">rassal say\u0131lar<\/i>dan problemin\u00a0<i id=\"yui_3_17_2_1_1539190980845_999\">\u00e7ok b\u00fcy\u00fck say\u0131larda<\/i>\u00a0\u00f6zel \u00e7\u00f6z\u00fcmleri elde edilerek,\u00a0<i id=\"yui_3_17_2_1_1539190980845_1000\">istatistik bilimi<\/i>nin temel yasas\u0131 olan\u00a0<a id=\"yui_3_17_2_1_1539190980845_1001\" href=\"http:\/\/www.akademikidea.org\/a-ders\/mod\/book\/edit.php?cmid=45&amp;id=1#_2.1_B%C3%BCy%C3%BCk_Say%C4%B1lar_Yasas%C4%B1\"><i>B\u00fcy\u00fck Say\u0131lar Yasas\u0131<\/i>(BSY)<\/a>\u2019s\u0131n\u0131n mant\u0131\u011f\u0131 ile ula\u015f\u0131l\u0131r.<\/p>\n<p>Sanal bir ger\u00e7e\u011fin do\u011frudan fiziksel bir ger\u00e7e\u011fe d\u00f6n\u00fc\u015ft\u00fcr\u00fclmesi atom bombas\u0131 \u00f6rne\u011finde oldu\u011fu gibi \u00f6ng\u00f6r\u00fclemeyen son derece sak\u0131ncal\u0131 sonu\u00e7lar do\u011furabilir. Bir zamanlar yer y\u00fcz\u00fcnde atom bombas\u0131 diye\u00a0bir \u015fey yoktu. Ancak, ge\u00e7en y\u00fczy\u0131l\u0131n ilk \u00e7eyre\u011finde, \u00e7ekirdek tepkimesiyle s\u00fcrekli enerji elde edilebilece\u011fi ger\u00e7ek deneylerle kan\u0131tlanm\u0131\u015ft\u0131. Bu s\u00fcrekli enerji yerine anl\u0131k bir enerji d\u00fc\u015f\u00fcnmek hi\u00e7 de zor de\u011fildir. On milyonluk bir b\u00fcy\u00fck\u015fehirin enerji gereksinimini y\u0131llarca sa\u011flayabilecek bir n\u00fckleer santral yerine, n\u00fckleer santral\u0131n yak\u0131t\u0131 olan\u00a01300gr kadar zenginle\u015ftirilmi\u015f uranyumdaki enerjiyi bir anda ortaya \u00e7\u0131kararak on milyonluk bir b\u00fcy\u00fck\u015fehiri yery\u00fcz\u00fcnden silecek bir bomba yapmak daha kolayd\u0131r.<\/p>\n<p>II. D\u00fcnya Sava\u015f\u0131 s\u0131ras\u0131nda d\u00fcnyay\u0131 yeniden payla\u015fmaya soyunan devletler\u00a0aras\u0131ndaki atom bombas\u0131 yar\u0131\u015f\u0131n\u0131, rakiplerine g\u00f6re daha \u00e7ok maddi ve insan kayna\u011f\u0131 ay\u0131rabilen A.B.D. kazand\u0131. Einstein\u2019\u0131n 2 A\u011fustos 1939\u2019da Ba\u015fkan Roosevelt\u2019e g\u00f6nderdi\u011fi bir mektuptan sonra, 1939\u2019dan 1945\u2019e kadar 2 milyar ABD dolar\u0131 harcanan Manhattan Projesi kapsam\u0131nda y\u00fcr\u00fct\u00fclen \u00e7al\u0131\u015fmalar\u0131n Nisan 1943 ile 1944 yaz\u0131 ortalar\u0131na kadar s\u00fcren son a\u015famas\u0131, kuramsal bilgideki bo\u015fluklar\u0131n doldurularak bir atom bombas\u0131n\u0131n tasar\u0131m\u0131 ve ger\u00e7ekle\u015ftirilmesine odakland\u0131. 6 A\u011fustos 1945\u2019te Hiroshima\u2019ya\u00a0<i>K\u00fc\u00e7\u00fck O\u011flan<\/i>\u00a0ve \u00fc\u00e7 g\u00fcn sonra da Nagasaki\u2019ye\u00a0<i>\u015ei\u015fman Adam<\/i>\u00a0at\u0131ld\u0131. Hiro\u015fima\u2019da 66 bin; Nagasaki\u2019de ise 39 bin insan bir saniye i\u00e7inde k\u00fcle d\u00f6nd\u00fc ve bir o kadar\u0131 da a\u011f\u0131r yaraland\u0131. Bombalar\u0131n d\u00fc\u015ft\u00fc\u011f\u00fc noktan\u0131n \u00e7evresindeki yar\u0131m mil \u00e7apl\u0131 \u00e7ember i\u00e7indeki her \u015fey buharla\u015ft\u0131; bir mil \u00e7apl\u0131 \u00e7ember i\u00e7inde ta\u015f ta\u015f \u00fcst\u00fcnde kalmad\u0131; iki mil \u00e7apl\u0131 \u00e7ember i\u00e7indeki yap\u0131lar\u0131n tamam\u0131 y\u0131k\u0131ld\u0131; iki bu\u00e7uk mil \u00e7apl\u0131 \u00e7ember i\u00e7inde her \u015fey yand\u0131; ve y\u0131k\u0131nt\u0131 par\u00e7alar\u0131 \u00fc\u00e7 milden daha b\u00fcy\u00fck \u00e7apl\u0131 bir \u00e7ember i\u00e7ine sa\u00e7\u0131ld\u0131. 10 A\u011fustos 1945\u2019te Japonlar teslim oldu.<\/p>\n<p>Hiro\u015fima ve Nagasaki\u2019de ger\u00e7ek deneyden hemen sonra g\u00f6zlenen atom bombas\u0131n\u0131n y\u0131k\u0131c\u0131 ve yak\u0131c\u0131 etkisi d\u0131\u015f\u0131nda \u00e7ekirdek \u0131\u015f\u0131n\u0131m\u0131n\u0131n, ba\u015fta insanlarda kan kanseri ve bitkilerde genetik de\u011fi\u015fme olmak \u00fczere yol a\u00e7t\u0131\u011f\u0131 \u00e7ok daha zararl\u0131 ve uzun s\u00fcreli sonu\u00e7lar daha sonra g\u00f6zlemlenebildi.<\/p>\n<p>Sanal bir ger\u00e7e\u011fin ayn\u0131 ko\u015fullar alt\u0131nda bir \u00e7ok kere canland\u0131r\u0131labilece\u011fini, farkl\u0131 ko\u015fullarda bu canland\u0131rman\u0131n yinelenebilece\u011fini, ve b\u00f6ylece\u00a0sanal ger\u00e7ek fiziksel bir ger\u00e7e\u011fe d\u00f6n\u00fc\u015fmeden \u00f6nce\u00a0matematiksel denklem a\u015famas\u0131ndayken \u00a0tasarlanan bir dizgenin olas\u0131 t\u00fcm sonu\u00e7lar\u0131n\u0131n \u00f6nceden g\u00f6r\u00fclebilece\u011fini, Manhattan Projesi&#8217;ndeki bilimcilerden bir olan Stanislaw Ulam fark etti:<\/p>\n<p>\u00ab\u2026\u00a0[Monte Carlo Y\u00f6ntemler]e ili\u015fkin ilk d\u00fc\u015f\u00fcncelerim ve giri\u015fimlerim, 1946\u2019da bir hastal\u0131ktan sonra iyile\u015fme d\u00f6nemimde\u00a0<i>yaln\u0131z oyunu<\/i>\u00a0oynarken akl\u0131ma gelen bir sorudan \u00e7\u0131kt\u0131: 52 kart\u0131n da\u011f\u0131t\u0131ld\u0131\u011f\u0131 bir yaln\u0131z oyununun ba\u015far\u0131yla sonu\u00e7lanma \u015fanslar\u0131 nedir? Salt bile\u015fim hesaplamalar\u0131yla tahmin etmek i\u00e7in bir s\u00fcr\u00fc zaman harcad\u0131ktan sonra, \u201csoyut d\u00fc\u015f\u00fcnceden\u201d, diyelim ki y\u00fcz kere kartlar\u0131 da\u011f\u0131t\u0131p ba\u015far\u0131l\u0131 olanlar\u0131 g\u00f6zlemek ve sayman\u0131n daha kolay bir y\u00f6ntem olup olmayaca\u011f\u0131n\u0131 merak ettim. Yeni h\u0131zl\u0131 bilgisayar d\u00f6neminin ba\u015flamas\u0131yla bunun art\u0131k yap\u0131labilir oldu\u011funu g\u00f6rd\u00fcm ve hemen \u00e7ekirdek yay\u0131n\u0131m\u0131 ve matematiksel fizi\u011fin di\u011fer sorunlar\u0131, ve daha genel olarak belli t\u00fcrevsel denklemlerle betimlenen s\u00fcre\u00e7lerin, rassal i\u015flemlerin ard\u0131ll\u0131\u011f\u0131 olarak yorumlanabilir denk s\u00fcre\u00e7lere nas\u0131l d\u00f6n\u00fc\u015ft\u00fcr\u00fclebilece\u011fi \u00fczerine d\u00fc\u015f\u00fcnmeye ba\u015flad\u0131m. Daha sonra\u2026. [1946\u2019da] d\u00fc\u015f\u00fcncemi John von Neumann\u2019a a\u00e7t\u0131m ve ger\u00e7ek hesaplamalar\u0131 planlamaya ba\u015flad\u0131k.\u00bb<\/p>\n<p>Bu d\u00fc\u015f\u00fcnce Von Neumann&#8217;\u0131n ilgisini \u00e7ekti.\u00a0 Yakla\u015f\u0131m, \u00f6zellikle n\u00f6tron zincirleme tepkimesinin \u00e7ekirdek par\u00e7alama ayg\u0131tlar\u0131ndaki davran\u0131\u015f\u0131n\u0131 ke\u015ffetmek i\u00e7in uygun g\u00f6r\u00fcn\u00fcyordu. \u00a0\u00d6zel olarak, n\u00f6tron par\u00e7alanma h\u0131zlar\u0131 tahmin edilebilir ve tasarlanmakta olan \u00e7e\u015fitli par\u00e7alan\u0131m silahlar\u0131n\u0131n davran\u0131\u015f\u0131n\u0131 ke\u015ffetmede kullan\u0131labilirdi. \u00a0Mart 1947&#8217;de, Los Alamos&#8217;taki Teorik B\u00f6l\u00fcm&#8217;\u00fcn \u00f6nderi olan\u00a0Robert Richtmyer&#8217;a, &#8220;istatistiksel yakla\u015f\u0131m\u0131n say\u0131sal bir i\u015flem i\u00e7in \u00e7ok uygun oldu\u011funu&#8221; ve kayna\u015f\u0131m ayg\u0131tlar\u0131ndaki n\u00f6tron yay\u0131n\u0131m ve art\u0131m sorunlar\u0131n\u0131n \u00e7\u00f6z\u00fclmesinde nas\u0131l kullan\u0131labilece\u011finin ana hatlar\u0131n\u0131 yazd\u0131.<\/p>\n<p>von Neumann, \u00a0n\u00f6tron yay\u0131n\u0131m\u0131n\u0131 modellemede yaln\u0131zca yar\u0131\u00e7ap\u0131 de\u011fi\u015fen \u00e7e\u015fitli nesenelerin bulundu\u011fu k\u00fcresel benze\u015fik bir geometri kulland\u0131. N\u00f6tronlar\u0131n izotropik olarak \u00fcretildi\u011fini, bilinen bir h\u0131z \u00a0izgesi oldu\u011funu, ve emilim, sa\u00e7\u0131l\u0131m, ve par\u00e7alan\u0131mlan\u0131r madde ve \u00e7evresindeki maddelerin par\u00e7alan\u0131m arakesitlerinin n\u00f6tron h\u0131z\u0131n\u0131n bir i\u015flevi ile betimlenebilece\u011fini varsayd\u0131. Son olarak da, her par\u00e7alan\u0131m s\u00fcrecindeki 2, 3, ya da 4 n\u00f6tron \u00fcretimi i\u00e7in belli olas\u0131l\u0131klarla par\u00e7alan\u0131m n\u00f6tronlar\u0131 say\u0131s\u0131n\u0131n istatistiksel \u00f6zelli\u011fine ili\u015fkin uygun bir varsay\u0131mda bulundu. Buna g\u00f6re yap\u0131lacak i\u015f, yol boyunca \u00e7e\u015fitli etkile\u015fimlerin sonu\u00e7lar\u0131n\u0131 se\u00e7mek i\u00e7in rasgele haneleri kullanarak belli bir n\u00f6tronun ge\u00e7mi\u015fini izlemekti. Bunun i\u00e7in von Neumann, hesaplamalarda her n\u00f6tronun\u00a0 maddenin neresinde oldu\u011fu, \u0131\u015f\u0131n\u0131m konumu, i\u00e7eri mi d\u0131\u015far\u0131 m\u0131 hareket etti\u011fi, h\u0131z\u0131, ve zaman\u0131 gibi \u00f6zelliklerinin i\u015flendi\u011fi 80-girdilik delikli bir bilgisayar kart\u0131 ile g\u00f6sterilebilece\u011fini d\u00fc\u015f\u00fcnd\u00fc. Kartlarda, iz uzunlu\u011fu ve y\u00f6n\u00fc, \u00e7arp\u0131\u015fma bi\u00e7imi, sa\u00e7\u0131l\u0131m sonras\u0131 h\u0131z gibi ge\u00e7mi\u015fteki bir sonraki ad\u0131m\u0131 belirlemede kullan\u0131lan &#8220;gerekli rassal de\u011ferler&#8221; de vard\u0131. \u00a0 \u0130zlenen n\u00f6tron sa\u00e7\u0131ld\u0131\u011f\u0131nda ya da bir ba\u015fka kavk\u0131ya ge\u00e7ti\u011finde yeni bir kartla yeni bir n\u00f6tron ba\u015flat\u0131l\u0131yor; n\u00f6tron bir par\u00e7alan\u0131m\u0131 tetiklediyse, \u00e7e\u015fitli n\u00f6tronlar i\u00e7in kartlar ba\u015flat\u0131l\u0131yordu. \u00a0\u0130lgilenilen ana niceliklerden biri, ba\u015flat\u0131lan her 100 n\u00f6tronun her biri i\u00e7in, \u00f6rne\u011fin \\( {10^{ &#8211; 8}} \\)\u00a0saniye sonra ka\u00e7 tane n\u00f6tron bulundu\u011funu g\u00f6steren n\u00f6tron art\u0131m h\u0131z\u0131yd\u0131.<\/p>\n<p>\u0130statistiksel benzetimin \u015fans oyunlar\u0131 benzetimine benzemesi ve Monte Carlo&#8217;nun bir kumar ve \u015fans oyunlar\u0131 merkezi olmas\u0131 nedeniyle Ulam&#8217;dan esinlenerek bu y\u00f6nteme &#8220;Monte Carlo&#8221; \u00a0s\u0131fat\u0131n\u0131\u00a0\u00a0<a href=\"http:\/\/scienceworld.wolfram.com\/biography\/Metropolis.html\">Metropolis<\/a>\u00a0 yak\u0131\u015ft\u0131rd\u0131.<\/p>\n<p><span id=\"eniac\"><strong><em><i>Monte Carlo Y\u00f6ntemin \u00d6z\u00fc<\/i><\/em><\/strong><\/span><\/p>\n<p>Monte Carlo y\u00f6ntemin \u00f6z\u00fc, ger\u00e7ek n\u00f6tron yay\u0131l\u0131m\u0131n\u0131 yakla\u015f\u0131klayan \u00f6rnekleri hesaplamak i\u00e7in her da\u011f\u0131l\u0131m\u0131n bir s\u00fcre\u00e7ler ard\u0131\u015f\u0131m\u0131ndaki \u00e7e\u015fitli maddelerin i\u00e7inde n\u00f6tronlar\u0131n yay\u0131l\u0131m\u0131 gibi belli bir s\u00fcreci yans\u0131tt\u0131\u011f\u0131 \u00e7e\u015fitli rasgele say\u0131lar\u0131n da\u011f\u0131l\u0131mlar\u0131n\u0131 kullanmaya dayan\u0131r. Olas\u0131l\u0131k da\u011f\u0131l\u0131mlar\u0131ndan rasgele \u00f6rnekleme daha \u00f6nceleri de biliniyordu. Ancak bu hesaplamalar\u0131 mekanik hesaplay\u0131c\u0131larla yapmak \u00f6yle yorucuydu ki,\u00a0 zorunluluk olmad\u0131\u011f\u0131 s\u00fcrece y\u00f6nteme \u00e7ok seyrek ba\u015fvuruluyordu. Bilgisayar bu yakla\u015f\u0131m\u0131 bir \u00e7ok fizik problemin \u00e7\u00f6z\u00fcm\u00fcnde son derece yararl\u0131 bir konuma getirdi.\u00a0 Monte Carlo y\u00f6ntemin etkinli\u011fini artt\u0131ran Metropolis&#8217;in \u00f6nem-\u00f6rneklemesi algoritmas\u0131\u00a0 gibi yeni teknikler nicel sonu\u00e7 elde etmeye y\u00f6nelik her t\u00fcrl\u00fc problemin \u00e7\u00f6z\u00fcm\u00fcnde y\u00f6ntemi daha da \u00e7ekici bir duruma getirdi.<\/p>\n<p>Bu sava\u015f zaman\u0131 d\u00f6neminde, Pennsylvania \u00dcniversitesi&#8217;ndeki \u00f6nderli\u011fini fizik\u00e7i John Mauchly ve m\u00fchendis Presper Eckert&#8217;in yapt\u0131\u011f\u0131 bilimci, m\u00fchendis, ve teknisyenlerden olu\u015fan\u00a0 bir tak\u0131m ilk elektronik bilgisayar ENIAC \u00fczerinde \u00e7al\u0131\u015f\u0131yordu. Mauchly, fizik\u00a0 laboratuvarlar\u0131ndaki\u00a0\u00a0Geiger saya\u00e7lar\u0131nda oldu\u011fu gibi\u00a0elektronik devrelerle sayma i\u015flemi yapabiliyorsa aritmetik i\u015flemlerin de yap\u0131labilece\u011fini ve di\u011fer bir \u00e7ok i\u015flem aras\u0131nda fark denklemlerinin de inan\u0131lmaz bir h\u0131zda \u00e7\u00f6z\u00fclebilece\u011fini fark etti.\u00a0 \u00a0Aberdeen&#8217;deki Balistik Ara\u015ft\u0131rma Laboratuar\u0131&#8217;nda y\u00fczlerce kollu hesap makinesi ile yap\u0131lan hesaplamalar\u0131n \u00e7\u0131kard\u0131\u011f\u0131 u\u011fultuyu ve zahmeti g\u00f6r\u00fcnce bu hesaplamalar\u0131n son derece h\u0131zl\u0131 ve g\u00fcr\u00fclt\u00fcs\u00fczce \u00fcstesinden gelecek bir bilgisayar yap\u0131m\u0131n\u0131 yetkililere \u00f6nerdi. \u0130leri Ara\u015ft\u0131rma Enstit\u00fcs\u00fc&#8217;nde Matematik Profes\u00f6r\u00fc olan John von Neumann, Aberdeen ve Los Alamos&#8217;ta da dan\u0131\u015fmand\u0131.\u00a0 Los Alamos&#8217;tayken Macar bilimci Edward Teller ve arkada\u015flar\u0131n\u0131n ortaya att\u0131\u011f\u0131 termon\u00fckleer problemle ciddi bi\u00e7imde ilgilenmi\u015fti. Monte Carlo y\u00f6ntemleri ve bu y\u00f6ntemlerin uygulanabilirli\u011fini sa\u011flayacak bilgisayarlar\u0131 tasarlayacak beyinler b\u00f6ylece bir araya geldi.<\/p>\n<p>Metropolis(1987), Monte Carlo y\u00f6ntemin en iyi a\u00e7\u0131klamas\u0131n\u0131n von Neumann&#8217;\u0131n Richtmyer&#8217;a yazd\u0131\u011f\u0131 mektupta tart\u0131\u015f\u0131lan \u00f6rnekle yap\u0131labilece\u011fini s\u00f6yl\u00fcyor:<\/p>\n<p>\u00ab&#8230;S\u0131kma\u00e7 bir madde kabu\u011fu i\u00e7inde par\u00e7alanabilen k\u00fcresel bir \u00e7ekirdek d\u00fc\u015f\u00fcn\u00fcn. N\u00f6tronlar\u0131n uzayda ve h\u0131zda bir ba\u015flang\u0131\u00e7 da\u011f\u0131l\u0131m\u0131 olsun, ancak \u0131\u015f\u0131n\u0131m ve ak\u0131\u015f devinimi g\u00f6z ard\u0131 edilsin.\u00a0 \u015eimdi ama\u00e7, sa\u00e7\u0131l\u0131m, emilim, par\u00e7alan\u0131m, ve s\u0131zman\u0131n bir sonucu b\u00fcy\u00fck bir say\u0131da bireysel n\u00f6tron zincirlerinin geli\u015fimini izlemektir.\u00a0 Her a\u015famada fiziksel ve geometrik etkenlere uygun istatistiksel olas\u0131l\u0131klara dayal\u0131 bir dizi karar verilmek zorundad\u0131r.\u00a0 \u0130lk iki karar belli bir h\u0131z ve mekansal konuma sahip bir n\u00f6tronun se\u00e7ildi\u011fi \\(t = 0\\) an\u0131nda verilir.\u00a0 Sonraki kararlar ilk \u00e7arp\u0131\u015fman\u0131n konumu ve o \u00e7arp\u0131\u015fman\u0131n do\u011fas\u0131d\u0131r.\u00a0 E\u011fer bir par\u00e7alanma belirlenmi\u015fse, a\u00e7\u0131\u011fa \u00e7\u0131kan n\u00f6tronlar\u0131n say\u0131s\u0131na karar verilmeli, ve bu n\u00f6tronlar\u0131n her biri sonunda ilkinde oldu\u011fu gibi izlenmelidir. \u00c7arp\u0131\u015fman\u0131n bir sa\u00e7\u0131l\u0131m oldu\u011funa karar verilirse, n\u00f6tronun yeni devinirli\u011fini belirlemek i\u00e7in uygun istatistikler devreye sokulur. N\u00f6tron maddesel bir s\u0131n\u0131r\u0131 a\u015farsa, yeni ortam\u0131n \u00f6l\u00e7\u00fcm\u00f6teleri ve \u00f6zellikleri g\u00f6z \u00f6n\u00fcne al\u0131n\u0131r. B\u00f6ylece, bir n\u00f6tronun kal\u0131t\u0131msal ge\u00e7mi\u015fi elde edilir. S\u00fcre\u00e7 istatistiksel a\u00e7\u0131dan ge\u00e7erli bir resim elde edilinceye kadar di\u011fer n\u00f6tronlar i\u00e7in de yinelenir.<\/p>\n<p>Tek d\u00fcze da\u011f\u0131l\u0131ml\u0131 bir s\u00f6zde-rassal say\u0131lar \u00fcreteci s\u00fcreci \u00e7al\u0131\u015ft\u0131rmak i\u00e7in gerekli temel girdiyi sa\u011flar. B\u00f6yle say\u0131lar \u00fcretmek i\u00e7in \u00e7ok\u00e7a kullan\u0131lan algoritma von Neumann&#8217;\u0131n &#8220;<i>orta-kare haneler<\/i>&#8221; idir. Burada,\u00a0<i>n<\/i>-haneli bir tam say\u0131n\u0131n karesi al\u0131narak 2<i>n<\/i>-haneli bir \u00e7arp\u0131m sonucu bulunur. Yeni bir tam say\u0131, \u00e7arp\u0131m sonucunun ortas\u0131ndaki\u00a0<i>n<\/i>-hane al\u0131narak olu\u015fturulur. Bu s\u00fcrecin \u00fcst \u00fcste yinelenmesi \u00f6zellikleri iyi bilinen bir tam say\u0131lar zinciri olu\u015fturur. A\u00e7\u0131kt\u0131r ki, say\u0131lar\u0131n bu zinciri bir H noktas\u0131ndan sonra kendisini yineler. H.Lehmer taraf\u0131ndan \u00f6nerilen b\u00f6yle bir zincirin kendisini yinelemeden \u00f6nce olas\u0131\u00a0<i>n<\/i>-haneli t\u00fcm say\u0131lar\u0131 \u00fcreten Kronecker-Weyl teoremine dayal\u0131 bir algoritma da vard\u0131r. Rassal say\u0131lar\u0131n tek d\u00fcze da\u011f\u0131l\u0131ml\u0131 bir k\u00fcmesi elde edilmi\u015fse, geriye bu say\u0131lar\u0131n istenen \u00f6zellikte tek d\u00fcze olmayan bir \\(g \\) da\u011f\u0131l\u0131ml\u0131 k\u00fcmeye d\u00f6n\u00fc\u015ft\u00fcr\u00fclmesi kal\u0131r. Bu d\u00f6n\u00fc\u015f\u00fcm\u00fc ba\u015farmak i\u00e7in gerekli \\(f \\) i\u015flevinin tek d\u00fcze olmayan \\(g \\) da\u011f\u0131l\u0131m\u0131n\u0131n yaln\u0131zca \\( f=g^{-1} \\) bi\u00e7imindeki ters i\u015flevi oldu\u011fu g\u00f6sterilebilir. \u00d6rne\u011fin n\u00f6tron fizi\u011fi \u00f6zg\u00fcr izlerin da\u011f\u0131l\u0131m\u0131n\u0131n-yani, belli bir madde i\u00e7inde belli bir enerjiye sahip n\u00f6tronlar\u0131n bir \u00e7ekirdekle \u00e7arp\u0131\u015fmadan \u00f6nce ne kadar yol alaca\u011f\u0131- \\( (0, \\infty ) \\) aral\u0131\u011f\u0131nda \u00fcstel olarak azald\u0131\u011f\u0131n\u0131 g\u00f6sterir. E\u011fer \\(x\\), \\( (0, 1)\\) a\u00e7\u0131k aral\u0131\u011f\u0131nda tek d\u00fcze da\u011f\u0131l\u0131ml\u0131 ise, o zaman \\(f = &#8211; lnx\\), tam bu \u00f6zelliklerde tek d\u00fcze olmayan bir \\(g\\) da\u011f\u0131l\u0131m\u0131 verir.<\/p>\n<p><b><i>\u00a0 \u00a0 \u00a0 \u00a0 \u00a0<\/i><\/b>\u00a0Manhattan Projesi kapsam\u0131nda kullan\u0131lmaya ba\u015flayan Monte Carlo y\u00f6ntemin uygulama alan\u0131 giderek geni\u015fledi ve uygulamadaki sorunlar y\u00f6ntemin kuramsal a\u00e7\u0131dan da zenginle\u015fmesine yol a\u00e7t\u0131. Karma\u015f\u0131k ve \u00e7ok-boyutlu t\u00fcmlevlerin hesaplanmas\u0131nda, say\u0131sal y\u00f6ntemlere g\u00f6re genellikle daha etkin bir yol olan Monte Carlo y\u00f6ntem ya da y\u00f6ntemi \u00f6nerenlerin tan\u0131mlad\u0131klar\u0131 bi\u00e7imde &#8220;olas\u0131l\u0131k da\u011f\u0131l\u0131mlar\u0131ndan rasgele \u00f6rnekleme&#8221;, istatistik\u00e7iler i\u00e7in do\u011fal olarak \u00e7ekici \u00f6zelli\u011fi olan bir y\u00f6ntemdi. \u0130statistik dilinde &#8220;rasgele \u00f6rnekleme&#8221;, ger\u00e7ek g\u00f6zlem birimlerinden olu\u015fan bir y\u0131\u011f\u0131ndan y\u0131\u011f\u0131n\u0131 temsil edecek bir g\u00f6zlem k\u00fcmesi olu\u015fturma amac\u0131 ile rasgele g\u00f6zlem birimi se\u00e7me anlam\u0131nda kullan\u0131l\u0131r. Temel ama\u00e7, g\u00f6zlem birimlerinin \u00f6l\u00e7\u00fclebilir \u00f6zellikleri olan rassal de\u011fi\u015fgenlerin beklenen de\u011ferlerini tahmin etmek ya da olas\u0131l\u0131k da\u011f\u0131l\u0131mlar\u0131n\u0131 ke\u015ffetmektir. B\u00fcy\u00fck Say\u0131lar Yasas\u0131&#8217;na g\u00f6re, \u00f6rnek \u00e7ap\u0131 b\u00fcy\u00fcd\u00fck\u00e7e \u00f6rnekteki g\u00f6zlem birimlerinden hesaplanan bir rassal de\u011fi\u015fgene ili\u015fkin \u00f6rnek istatisti\u011finin giderek s\u00f6z konusu rassal de\u011fi\u015fgenin beklenen de\u011feri ya da y\u0131\u011f\u0131n \u00f6l\u00e7\u00fcm\u00f6tesini belli bir hata pay\u0131 ile yak\u0131nsar.<\/p>\n<p>Ger\u00e7ek ya da sanal ger\u00e7ek olsun, bir dizgenin modeli kurulabiliyorsa, belirlenen konumlarda dizge say\u0131sal olarak canland\u0131r\u0131labilir ve \u00e7\u0131kt\u0131s\u0131 \u00e7\u00f6z\u00fcmlenebilir. Bir dizgenin say\u0131sal olarak canland\u0131r\u0131lmas\u0131 ya da benzetimi, dizgenin g\u00f6zlenmesine g\u00f6re her a\u00e7\u0131dan \u00e7ok daha az maliyetli ve \u00e7ok daha az zaman al\u0131c\u0131d\u0131r. Tasarlanan sanal ger\u00e7eklerin olas\u0131 durumlar\u0131 ve sonu\u00e7lar\u0131 Monte Carlo y\u00f6ntemlerle de\u011ferlendirilmeden ger\u00e7ek d\u00fcnyada uygulamaya konulamayaca\u011f\u0131 konusunda, atom bombas\u0131 deneyimi, bilim ve teknik alanlarda \u00e7al\u0131\u015fan her kes kadar son karar vericileri de uyaran \u00e7arp\u0131c\u0131 bir \u00f6rnektir. MC y\u00f6ntemlerin kayna\u011f\u0131 olarak bilinen Manhattan Projesi kapsam\u0131nda geli\u015ftirilen ilk sanal atom bombas\u0131, MC s\u0131namalardan ge\u00e7irilmeden, k\u00fc\u00e7\u00fck bir ger\u00e7e\u011fi 1944\u2019te Los Alamos \u00e7\u00f6llerinde ve as\u0131llar\u0131 da 1945\u2019te Hiro\u015fima ve Nagazaki \u00fczerinde denendi. Manhattan Projesi\u2019nin MC y\u00f6ntemlere katk\u0131s\u0131, atom bombas\u0131n\u0131n sava\u015f\u0131 sonland\u0131rma d\u0131\u015f\u0131nda \u00f6ng\u00f6r\u00fclemeyen sonu\u00e7lar\u0131 g\u00f6zlendikten sonra olmu\u015ftur. Sava\u015f sonras\u0131nda ise, t\u00fcm sanal n\u00fckleer sava\u015f benzetimleri b\u00f6yle bir sava\u015f\u0131n galibi olamayaca\u011f\u0131n\u0131 g\u00f6sterdi\u011fi i\u00e7in, so\u011fuk sava\u015f d\u00f6neminde n\u00fckleer silahlar, bu teknolojiye sahip olmayanlara \u201caba alt\u0131ndan g\u00f6sterilen\u201d ka\u011f\u0131ttan sopalara d\u00f6n\u00fc\u015ft\u00fc.\u00a0\u00a0Silahlanma yar\u0131\u015f\u0131n\u0131n hi\u00e7 kesilmedi\u011fi, hatta tekelle\u015fti\u011fi g\u00fcn\u00fcm\u00fczde, atom bombas\u0131ndan \u00e7ok daha g\u00fc\u00e7l\u00fc oldu\u011fu bilinen silahlar\u0131n bu g\u00fcne kadar canl\u0131lar \u00fczerinde denenmemi\u015f olmas\u0131, bilimcilerin ve karar vericilerin bu konuda belli bir bilin\u00e7 d\u00fczeyine geldi\u011fini g\u00f6steriyor.<\/p>\n<p>G\u00fcn\u00fcm\u00fczde tasarlanan bir dizgenin sanal ortamdan ger\u00e7ek ortama aktar\u0131lmas\u0131, MC sanal deney a\u015famas\u0131ndan ba\u015far\u0131 ile ge\u00e7ebilmesine ba\u011fl\u0131d\u0131r. Sanal bir deneyle, tasar\u0131m a\u015famas\u0131ndaki bir dizge canland\u0131r\u0131larak, istenen her ko\u015fulda dizgenin i\u015fleyi\u015fi incelenebilir. MC benzetim s\u0131namalar\u0131ndan ba\u015far\u0131 ile ge\u00e7tikten sonra, bir dizgenin ger\u00e7ek ortamda g\u00f6zlenecek davran\u0131\u015f\u0131 ile sanal deney a\u015famas\u0131ndaki davran\u0131\u015f\u0131 aras\u0131ndaki fark, dizgenin modeli ile dizgenin kendisi aras\u0131ndaki fark kadard\u0131r. Ba\u015fka bir deyi\u015fle, sanal deneyin temelini olu\u015fturan bir dizgeye ili\u015fkin modelin hatas\u0131 ne kadar az ise, s\u00f6z konusu dizgeye ili\u015fkin sanal deneyle elde edilen bilgi ile o dizgeye ili\u015fkin olarak ger\u00e7ekle\u015ftirilecek bir deneyden elde edilecek bilgi ile o kadar \u00e7ok \u00f6rt\u00fc\u015fecektir. Bu a\u00e7\u0131klamalar\u0131n \u0131\u015f\u0131\u011f\u0131nda, MC y\u00f6ntemlerin, nicel temeli olan her t\u00fcrl\u00fc kuramsal bilginin sanal verilerle s\u0131nanmas\u0131nda g\u00fcvenle kullan\u0131labilece\u011fi a\u00e7\u0131kt\u0131r.<\/p>\n<div id=\"yui_3_17_2_1_1539190980845_812\">\n<p><b>Ba\u015fvurular<\/b><\/p>\n<p>[1]\u00a0<a href=\"http:\/\/www.sciencemadness.org\/lanl1_a\/lib-www\/pubs\/00326867.pdf\" target=\"_blank\" rel=\"noopener\">Eckhart, Roger(1987)<\/a>\u00a0Stan Ulam, von Neumann, and the Monte Carlo Method,\u00a0<i>Los Alamos Science Special Issue<\/i><a href=\"http:\/\/www.akademikidea.org\/a-ders\/mod\/book\/=\" target=\"_blank\" rel=\"noopener\">,131-137.<\/a><\/p>\n<p><a href=\"http:\/\/www.akademikidea.org\/a-ders\/mod\/book\/=\" target=\"_blank\" rel=\"noopener\">[2]\u00a0<\/a><a href=\"http:\/\/permalink.lanl.gov\/object\/tr?what=info:lanl-repo\/lareport\/LA-UR-86-2600-05\" target=\"_blank\" rel=\"noopener\">Anderson, L. Herbert (1986)<\/a>\u00a0Metropolis, Monte Carlo, and the MANIAC,\u00a0<i>Los Alamos Science Special Issue<\/i>, 96-107.<\/p>\n<p>[3]\u00a0<a href=\"http:\/\/permalink.lanl.gov\/object\/tr?what=info:lanl-repo\/lareport\/LA-UR-88-9067\" target=\"_blank\" rel=\"noopener\">Metropolis, Nickolas(1987)\u00a0<\/a>The Beginning of the Monte Carlo Method, \u00a0<i>Los Alamos Science Special Issue<\/i>, 125-130.<\/p>\n<p>[4]\u00a0<a href=\"http:\/\/www.lanl.gov\/orgs\/n\/n1\/panda\/00326409.pdf\" target=\"_blank\" rel=\"noopener\">Stewar, J. E. (?)<\/a>\u00a0Principles of Total Neutron\u00a0Counting.<\/p>\n<p>[5]\u00a0<a href=\"https:\/\/books.google.com.tr\/books?id=H-w8AAAAIAAJ&amp;pg=PA1115&amp;lpg=PA1115&amp;dq=neutron+multiplication+rate&amp;source=bl&amp;ots=Nu9C38BE1z&amp;sig=PhOaG3NGv54yQBLoc4RY0Ma267g&amp;hl=tr&amp;sa=X&amp;ved=0ahUKEwiB7JiF7ZDWAhVCLZoKHZF_D-kQ6AEIQzAE#v=onepage&amp;q=neutron%20multiplication%20rate&amp;f=false\" target=\"_blank\" rel=\"noopener\">Dirac, P.A.M. (1943)\u00a0<\/a>Approximate Rate of Neutron Multiplication for a Solid of Arbitrary Shape and Uniform Density, in (ed.)\u00a0<i>Collected Works of P.A.M.Dirac 1928-1948<\/i>, Cambridge University Press, 1995, pp1115-.<\/p>\n<p>[6]\u00a0<span data-reactid=\"77\"><a href=\"https:\/\/www.researchgate.net\/publication\/231961710_Critical_conditions_in_neutron_multiplication\" target=\"_blank\" rel=\"noopener\">Peierls,\u00a0R.\u00a0(1939)<\/a>\u00a0<\/span>Critical conditions in neutron multiplication,\u00a0<span data-reactid=\"56\"><i>Mathematical Proceedings of the Cambridge Philosophical Society,<\/i>\u00a035(04):610 &#8211; 615<\/span><span data-reactid=\"61\">.<\/span><\/p>\n<p><span data-reactid=\"61\">[7]\u00a0<\/span><a href=\"http:\/\/citeseerx.ist.psu.edu\/viewdoc\/download;jsessionid=2B1D21E236ADB92DE245784848F4E276?doi=10.1.1.591.8465&amp;rep=rep1&amp;type=pdf\" target=\"_blank\" rel=\"noopener\">Robert, Chiristian(2009)\u00a0<\/a>Monte Carlo Methods in Statistics,<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>&nbsp; Kumarhaneleri ile \u00fcnl\u00fc Monoca Prensli\u011fi\u2019nin bir kenti olan \u201cMonte Carlo\u201d, ilk kez 1940\u2019larda A.B.D.\u2019nin\u00a0 Los Alamos Laboratuar\u0131&#8217;nda atom bombas\u0131 \u00e7al\u0131\u015fmalar\u0131n\u0131n yap\u0131ld\u0131\u011f\u0131\u00a0 Manhattan Projesi&#8217;nde bir araya gelen\u00a0John von Neumann(1903-1957), Stanislav Ulam(1909-1986) ve Nicholas Constantine\u00a0Metropolis(1915-1999) gibi bilimciler taraf\u0131ndan, bir grup matematiksel y\u00f6ntemleri nitelendirmek i\u00e7in kullan\u0131ld\u0131. Bu y\u00f6ntemleri ayn\u0131 amaca y\u00f6nelik di\u011fer say\u0131sal y\u00f6ntemlerden ay\u0131ran temel \u00f6zellikleri,&#8230;<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[31],"tags":[],"class_list":["post-1511","post","type-post","status-publish","format-standard","hentry","category-istatistiksel-yontemler"],"_links":{"self":[{"href":"https:\/\/www.akademikidea.org\/a-kitap\/wp-json\/wp\/v2\/posts\/1511","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.akademikidea.org\/a-kitap\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.akademikidea.org\/a-kitap\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.akademikidea.org\/a-kitap\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.akademikidea.org\/a-kitap\/wp-json\/wp\/v2\/comments?post=1511"}],"version-history":[{"count":3,"href":"https:\/\/www.akademikidea.org\/a-kitap\/wp-json\/wp\/v2\/posts\/1511\/revisions"}],"predecessor-version":[{"id":1986,"href":"https:\/\/www.akademikidea.org\/a-kitap\/wp-json\/wp\/v2\/posts\/1511\/revisions\/1986"}],"wp:attachment":[{"href":"https:\/\/www.akademikidea.org\/a-kitap\/wp-json\/wp\/v2\/media?parent=1511"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.akademikidea.org\/a-kitap\/wp-json\/wp\/v2\/categories?post=1511"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.akademikidea.org\/a-kitap\/wp-json\/wp\/v2\/tags?post=1511"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}