![\"\"](\"https:\/\/bilimvegelecek.com.tr\/wp-content\/uploads\/2019\/06\/2-25-300x124.jpg\")
<\/p>\nBilim tarihinde Helenistik d\u00f6nem (M.\u00d6. 300 -M.S. 100), \u00f6zellikle ilk a\u015famas\u0131nda, bilimsel y\u00f6ntemin ger\u00e7ek anlamda i\u015flerlik kazand\u0131\u011f\u0131 ya\u00adrat\u0131c\u0131 bir ortamd\u0131r. Daha \u00f6nceki bilimsel \u00e7al\u0131\u015f\u00admalar ya M\u0131s\u0131r ve Mezopotamya’da oldu\u011fu gibi daha \u00e7ok pratik ama\u00e7lara y\u00f6nelik g\u00f6zlem ve \u00f6l\u00e7\u00adme d\u00fczeyinde kalan bir etkinlikti, ya da, Antik Grek d\u00f6neminde oldu\u011fu gibi g\u00f6zlemden \u00e7ok ku\u00adramsal d\u00fc\u015f\u00fcnmeye a\u011f\u0131rl\u0131k veren, varl\u0131\u011f\u0131n do\u011fa\u00ads\u0131n\u0131 anlamaya y\u00f6nelik metafiziksel t\u00fcrden bir u\u011fra\u015ft\u0131. Thales’den Aristoteles’e uzanan \u00fc\u00e7y\u00fcz y\u0131ll\u0131k d\u00fc\u015f\u00fcnsel aray\u0131\u015f\u0131n ba\u015fl\u0131ca hedefi ger\u00e7ekli\u00ad\u011fin asal niteli\u011fini belirlemekti. Grek d\u00fc\u015f\u00fcn\u00fcrle\u00adri aras\u0131nda olgusal ara\u015ft\u0131rmaya belki de en yat\u00adk\u0131n olan Aristoteles bile, temelde, kimi metafi\u00adziksel ilkelere dayanan b\u00fct\u00fcnc\u00fcl bir a\u00e7\u0131klama aray\u0131\u015f\u0131 i\u00e7indeydi. Ussal d\u00fc\u015f\u00fcnme ile g\u00f6zlemsel verilerin etkile\u015fimini i\u00e7eren bilimsel y\u00f6ntemin ilk yetkin \u00f6rne\u011fini Helenistik d\u00f6nemin ba\u015fta Archimedes (Ar\u015fimet) olmak \u00fczere say\u0131l\u0131 se\u00e7kin bilginlerinin \u00e7al\u0131\u015fmalar\u0131nda bulmaktay\u0131z.<\/p>\n
Ar\u015fimet, bundan \u00f6nceki yaz\u0131da ayr\u0131nt\u0131l\u0131 ola\u00adrak belirtti\u011fimiz gibi bulu\u015flar\u0131yla klasik \u00e7a\u011f\u0131n bilimde en b\u00fcy\u00fck \u00f6nc\u00fcs\u00fcd\u00fcr. \u00c7a\u011fda\u015f\u0131 Aristarkus, Kopernik’ten 1700 y\u0131l \u00f6nce, g\u00fcne\u015f-merkezli sistem hipotezini ilk ortaya s\u00fcren b\u00fcy\u00fck bir ast\u00adronomdu. Onun \u00f6ng\u00f6rd\u00fc\u011f\u00fc sistem \u00e7er\u00e7evesinde (s.62) g\u00fcne\u015f ile y\u0131ld\u0131zlar\u0131n g\u00f6ky\u00fcz\u00fcnde sabit konum\u00adlarda oldu\u011fu, arz\u0131n ise g\u00fcne\u015f \u00e7evresinde \u00e7embersel bir y\u00f6r\u00fcnge \u00e7izerek devindi\u011fi, dahas\u0131 ken\u00addi ekseni \u00e7evresinde de g\u00fcnl\u00fck d\u00f6n\u00fc\u015f i\u00e7inde ol\u00addu\u011fu t\u00fcr\u00fcnden, d\u00f6nemin yerle\u015fik anlay\u0131\u015f\u0131na ters d\u00fc\u015fen savlar ortaya koymu\u015ftu. Ayr\u0131ca, yaz\u00add\u0131\u011f\u0131 bir kitapta G\u00fcne\u015f ile Ay’\u0131n oylumlar\u0131n\u0131, d\u00fcnyadan uzakl\u0131klar\u0131n\u0131 hesaplamaya, ula\u015ft\u0131\u011f\u0131 sonu\u00e7lar\u0131 geometri y\u00f6ntemiyle ispatlamaya \u00e7a\u00adl\u0131\u015ft\u0131\u011f\u0131 g\u00f6r\u00fclmektedir.<\/p>\n
Eratosthenes’e gelince, bu \u00e7ok y\u00f6nl\u00fc bilgin i\u00e7in hi\u00e7 ku\u015fkusuz d\u00f6nemin Ar\u015fimet’ten sonra en b\u00fcy\u00fck \u00f6nc\u00fcs\u00fc diyebiliriz. Geni\u015f bilgisi, pek \u00e7ok konularda yazd\u0131\u011f\u0131 kitaplar\u0131yla daha ya\u015fam d\u00f6\u00adneminde \u00fcn kazanan Erastothenes, \u0130skenderiye b\u00fcy\u00fck k\u00fct\u00fcphanesinin y\u00f6neticisiydi. Arz\u0131n k\u00fc\u00adresel oldu\u011funu ileri s\u00fcren, g\u00fcne\u015fin d\u00fcnyadan uzakl\u0131\u011f\u0131n\u0131 92 milyon mil olarak hesaplayan (do\u011frusu 93 milyon mildir), Eratosthenes, \u00f6zel\u00adlikle co\u011frafya alan\u0131ndaki \u00e7al\u0131\u015fmalar\u0131yla tan\u0131n\u00admaktayd\u0131. Ama onu bilim tarihinde unutulmaz\u00adlar aras\u0131na sokan as\u0131l ba\u015far\u0131s\u0131, arz\u0131n \u00e7evrel \u00e7em\u00adberinin uzunlu\u011funu belirleme \u00e7al\u0131\u015fmas\u0131d\u0131r. De\u00adniz ve kara ula\u015f\u0131m\u0131n\u0131n bir ka\u00e7 bin millik a\u00e7\u0131l\u00admayla s\u0131n\u0131rl\u0131 kald\u0131\u011f\u0131 bir d\u00f6nemde arz\u0131n b\u00fcy\u00fck\u00adl\u00fc\u011f\u00fcn\u00fc belirleme kolayca ula\u015f\u0131labilecek bir ba\u00ad\u015far\u0131 de\u011fildi. Daha \u00f6nce bu y\u00f6nde u\u011fra\u015f veren pek \u00e7ok kimse olmu\u015ftu; ama hi\u00e7 biri Eratosthenes’in ula\u015ft\u0131\u011f\u0131 sonu\u00e7 \u00f6l\u00e7\u00fcs\u00fcnde ger\u00e7e\u011fe yak\u0131n bir sonu\u00e7 ortaya koyamam\u0131\u015ft\u0131. As\u0131l amac\u0131 g\u00fcne\u015f ile Ay’\u0131n boyutlar\u0131n\u0131 belirlemek, d\u00fcnyadan uzak\u00adl\u0131klar\u0131n\u0131 saptamakt\u0131. Ama bunun i\u00e7in \u00f6ncelikle arz\u0131n b\u00fcy\u00fckl\u00fc\u011f\u00fcn\u00fc hesaplamas\u0131 gerekiyordu. Elde yararlanabilece\u011fi hi\u00e7 bir optik ara\u00e7 yoktu.G\u00fc\u00e7 kayna\u011f\u0131n\u0131, uygulad\u0131\u011f\u0131 y\u00f6ntem sa\u011fl\u0131yordu. Basit btrbrant\u0131ya dayanan y\u00f6ntemin kullan\u0131m\u0131 baz\u0131 varsay\u0131m, g\u00f6zlemsel bilgi ve geometrik ku\u00adrallar gerektiriyordu. \u00d6rne\u011fin, arz\u0131n k\u00fcreselli\u011fi, daire \u00e7emberinin 360 derece oldu\u011fu, g\u00fcne\u015f \u0131\u015f\u0131n\u00adlar\u0131n\u0131n yer y\u00fcz\u00fcne paralel d\u00fc\u015ft\u00fc\u011f\u00fc, vb. Bilindi\u011fi gibi, yer y\u00fczeyi d\u00fcz de\u011fil, e\u011fme\u00e7lidir. Bu neden\u00adle g\u00fcn ortas\u0131nda g\u00fcne\u015f de\u011fi\u015fik enlemlerde bulu\u00adnan ki\u015filere, ufuktan de\u011fi\u015fik y\u00fcksekliklerde g\u00f6\u00adr\u00fcn\u00fcr. Bu g\u00f6zlemi dikkate alan Eratosthenes yakla\u015f\u0131k ayn\u0131 boylam \u00fczerine d\u00fc\u015fen iki yer se\u00ad\u00e7er. Bunlardan biri Syene (bug\u00fcnk\u00fc Asvan ba\u00adraj\u0131na yak\u0131n k\u00fc\u00e7\u00fck bir kasaba), di\u011feri d\u00f6nemin \u00fcnl\u00fc bilim merkezi \u0130skenderiye kenti idi. Syene’de yaz ortas\u0131nda g\u00fcne\u015f \u00f6\u011fle vakti tam tepede bir konumdad\u0131r; \u00f6yle ki, dik duran bir direk g\u00f6l\u00adge d\u00fc\u015f\u00fcremedi\u011fi gibi, derin bir kuyu dibinden bak\u0131ld\u0131\u011f\u0131nda g\u00fcne\u015f g\u00f6r\u00fcl\u00fcr. \u0130skenderiye’de ise durum de\u011fi\u015fiktir; Syene’nin yakla\u015f\u0131k 514 mil kuzeyinde bulunan bu kentte g\u00fcne\u015f \u0131\u015f\u0131nlan hi\u00e7 bir zaman dik d\u00fc\u015fmez. Eratosthemes bu verile\u00adre dayanarak a\u015fa\u011f\u0131daki \u015fekilde g\u00f6sterildi\u011fi \u00fcze\u00adre, \u0130skenderiye’de g\u00fcne\u015f \u0131\u015f\u0131nlar\u0131n\u0131n, arz\u0131n mer\u00adkezine dik inen bir do\u011fru \u00fczerinde olu\u015fturdu\u011fu a\u00e7\u0131y\u0131 (\u015fekilde a ile g\u00f6sterilen a\u00e7\u0131y\u0131) \u00f6l\u00e7er. Ad\u0131 ge\u00ad\u00e7en iki yerin arz\u0131n merkezinde olu\u015fturduklar\u0131 a\u00e7\u0131ya e\u015fit olan ve iki yer aras\u0131ndaki mesafeyi temsil eden bu a\u00e7\u0131 yakla\u015f\u0131k 7.5 derecedir. Her daire \u00e7emberi gibi yer k\u00fcrenin \u00e7evrel \u00e7emberi\u00adnin de 360 derece oldu\u011funu varsayan Eratosthe\u00adnes basit bir orant\u0131 i\u015flemiyle bu \u00e7emberin 24.670 mil oldu\u011funu (do\u011frusu 24.870 mildir) he\u00adsaplar. Bu kadarla kalmaz, 60 millik bir hatayla arz\u0131n \u00e7ap\u0131n\u0131 da belirler.<\/p>\n
Teknolojinin hen\u00fcz baz\u0131 basit el ara\u00e7lar\u0131n\u0131n \u00f6tesine ge\u00e7medi\u011fi bir d\u00f6nemde bu t\u00fcrden sonu\u00e7la\u00adra ula\u015fma ger\u00e7ekten ola\u011fan\u00fcst\u00fc bir zek\u00e2 ve imge\u00adlem g\u00fcc\u00fc demekti.<\/p>\n
Eratosthenes’in az\u0131msanamayacak bir ba\u015far\u0131s\u0131 da o zaman bilinen d\u00fcnyan\u0131n haritas\u0131n\u0131 \u00e7\u0131karma\u00ads\u0131. Harita \u0130ngiliz adalar\u0131 dahil Avrupa, Afrika ve Asya anakaralar\u0131n\u0131 kaps\u0131yordu. K\u00fcresel bir y\u00fcze\u00adyi d\u00fcz ka\u011f\u0131t \u00fcst\u00fcnde g\u00f6stermek kolay bir i\u015f de\u011fil\u00addi. T\u0131pk\u0131 bir portakal kabu\u011funu masa \u00fczerine d\u00fcmd\u00fcz yerle\u015ftirmek gibi. Eratosthenes enlem paralelleriyle boylam meridyenlerini kullanarak olduk\u00e7a duyarl\u0131 ve g\u00fcvenilir bir projeksiyonla g\u00fc\u00e7\u00adl\u00fc\u011f\u00fcn \u00fcstesinden gelmi\u015fti. Yapt\u0131\u011f\u0131 harita y\u00fczy\u0131l\u00adlarca denizcilikte ve ba\u015fka alanlarda kullan\u0131ld\u0131.<\/p>\n
Eratosthenes, geli\u015ftirdi\u011fi bir y\u00f6ntemle, g\u00fcne\u00ad\u015fin \u00f6\u011fle vaktindeki y\u00fcksekli\u011fine bakarak herhan\u00adgi bir yerin enlemini hesaplayabiliyordu (Boylam\u0131n hesaplanmas\u0131 aradan ikibin y\u0131ll\u0131k bir s\u00fcrenin ge\u00e7mesini beklemi\u015ftir). Onun ilgin\u00e7 bir sav\u0131 da fiziksel co\u011frafya ile ilgilidir. Hint ve Atlas okyanuslar\u0131ndaki gel-git devinimleri aras\u0131ndaki yak\u0131n benzerli\u011fi g\u00f6z \u00f6n\u00fcne alarak, iki okyanusun asl\u0131nda birle\u015fik oldu\u011funu, \u00fc\u00e7 anakaran\u0131n (Avrupa, Asya ve Afrika) da bir ada olu\u015fturdu\u011funu ileri s\u00fcrer. Dahas\u0131, kimi kaynaklara g\u00f6re, Eratosthenes daha ileri giderek Atlantik \u00f6tesi yeni bir anakaran\u0131n varl\u0131\u011f\u0131ndan bile s\u00f6z etmi\u015ftir. Ona g\u00f6re, okyanusun \u00f6te yakas\u0131n\u00adda bilinen d\u00fcnyay\u0131 dengeleyen bir ba\u015fka d\u00fcn\u00adyan\u0131n varl\u0131\u011f\u0131 b\u00fcy\u00fck bir olas\u0131l\u0131kt\u0131.<\/p>\n
Roma y\u00f6netiminde zamanla \u0130skenderiye’deki parlak bilim me\u015falesi s\u00f6nmeye y\u00fcz tutar. O d\u00f6nemin bilim \u00f6nc\u00fclerinin son temsilcisi Hero’nun matematik, fizik ve teknolojideki ba\u015far\u0131lar\u0131m, kendisinden 300 y\u0131l \u00f6nce ya\u015fam\u0131\u015f Eratosthenes’e bor\u00e7lu oldu\u011funu s\u00f6ylemi\u015f olmas\u0131 b\u00fcy\u00fck bilginin bilim d\u00fcnyas\u0131ndaki kal\u0131c\u0131 et\u00adkisini yans\u0131tmaktad\u0131r.<\/p>\n
Eratosthenes 81 ya\u015f\u0131nda \u00f6ld\u00fc\u011f\u00fcnde en k\u00fc\u00e7\u00fck bir mal varl\u0131\u011f\u0131 yoktu; ama b\u0131rakt\u0131\u011f\u0131 d\u00fcnya do\u011fdu\u011fundaki d\u00fcnyadan bilgi birikimi ve ara\u015ft\u0131rma y\u00f6ntemi bak\u0131m\u0131ndan \u00e7ok daha zengindi.<\/p>\n
Kaynak: <\/strong>Cemal Y\u0131ld\u0131r\u0131m, Bilimin \u00d6nc\u00fcleri, Bilim ve Gelecek Kitapl\u0131\u011f\u0131,28.Bask\u0131,2014,s.64-69<\/p>\n","protected":false},"excerpt":{"rendered":" Bilim tarihinde Helenistik d\u00f6nem (M.\u00d6. 300 -M.S. 100), \u00f6zellikle ilk a\u015famas\u0131nda, bilimsel y\u00f6ntemin ger\u00e7ek anlamda i\u015flerlik kazand\u0131\u011f\u0131 ya\u00adrat\u0131c\u0131 bir ortamd\u0131r. Daha \u00f6nceki bilimsel \u00e7al\u0131\u015f\u00admalar ya M\u0131s\u0131r ve Mezopotamya’da oldu\u011fu gibi daha \u00e7ok pratik ama\u00e7lara y\u00f6nelik g\u00f6zlem ve \u00f6l\u00e7\u00adme d\u00fczeyinde kalan bir etkinlikti, ya da, Antik Grek d\u00f6neminde oldu\u011fu gibi g\u00f6zlemden \u00e7ok ku\u00adramsal d\u00fc\u015f\u00fcnmeye a\u011f\u0131rl\u0131k veren, […]<\/p>\n","protected":false},"author":429,"featured_media":34921,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[3845],"tags":[1116,787,482,4953,288,795,4954],"class_list":["post-34919","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bilimin-onculeri","tag-arsimet","tag-ay","tag-bilim","tag-eratoshenes","tag-fizik","tag-gunes","tag-oprik"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t