René Maurice Fréchet
René Maurice Fréchet ( [ʁəne mɔʁis fʁeʃɛ, moʁ-]; 2 ga Satumba 1878 - 4 ga Yuni 1973) masanin lissafi ne na Faransa. Ya ba da gudummawa sosai ga ilimin lissafi na gaba ɗaya kuma shine na farko da ya bayyana sararin ma'auni. Ya kuma ba da gudummawa da yawa ga fannin kididdiga da yiwuwar, da lissafi. Rubutun nasa ya buɗe dukkan fannin aiki a kan sararin ma'auni kuma ya gabatar da ra'ayin compactness. Ba tare da Riesz ba, ya gano ka'idar wakilci a cikin sararin Ayyukan Lebesgue square integrable. Sau da yawa ana kiransa wanda ya kafa ka'idar sararin samaniya.[1]
Tarihin rayuwa
[gyara sashe | gyara masomin]Rayuwa ta farko
[gyara sashe | gyara masomin]An haife shi ne a cikin iyalin Furotesta a Maligny ga Jacques da Zoé Fréchet . A lokacin da aka haife shi, mahaifinsa ya kasance darektan gidan marayu na Protestant a Maligny kuma daga baya aka nada shi shugaban makarantar Protestant; amma a karkashin Dokokin Jules Ferry ya rasa aikinsa. Mahaifiyarsa ta kafa gidan kwana ga baƙi a birnin Paris; kuma a lokacin da ya dace mahaifinsa ya sami matsayin koyarwa a cikin tsarin duniya.
Maurice ya halarci makarantar sakandare ta Lycée Buffon a Paris inda Jacques Hadamard ya koya masa lissafi. Hadamard ya fahimci damar saurayi Maurice kuma ya yanke shawarar koyar da shi a kan mutum. Bayan Hadamard ya koma Jami'ar Bordeaux a shekara ta 1894, Hadamard ta ci gaba da rubuta wa Fréchet, ta sa shi matsalolin lissafi kuma ta soki kuskuren da ya yi. Daga baya Fréchet ya yarda cewa matsalolin sun sa ya zauna cikin ci gaba da tsoron rashin iya warware wasu daga cikinsu, duk da cewa yana da godiya sosai ga dangantakar ta musamman da Hadamard da yake da dama don jin daɗi.
Rayuwa ta tsakiya
[gyara sashe | gyara masomin]Fréchet ya yi aiki a cibiyoyi daban-daban a lokacin aikinsa na ilimi. Daga 1907 zuwa 1908 ya yi aiki a matsayin farfesa na lissafi a Lycée a Besançon, sannan ya koma a 1908 zuwa Lycée a Nantes don zama a can na shekara guda. Bayan haka ya yi aiki a Jami'ar Poitiers tsakanin 1910 da 1919.
A shekara ta 1908 ya auri Suzanne Carrive (1881-1945). Suna da 'ya'ya hudu: Hélène, Henri, Denise da Alain .
Yaƙin Duniya na farko
[gyara sashe | gyara masomin]Fréchet yana shirin yin shekara guda a Amurka a Jami'ar Illinois, amma shirinsa ya rushe lokacin da Yaƙin Duniya na farko ya ɓarke a shekara ta 1914. An tattara shi a ranar 4 ga watan Agusta a wannan shekarar. Saboda ƙwarewarsa ta harshe daban-daban, wanda ya samu lokacin da mahaifiyarsa ta gudanar da kafa don baƙi, ya yi aiki a matsayin mai fassara ga Sojojin Burtaniya. Koyaya, wannan ba aiki ne mai aminci ba; ya shafe shekaru biyu da rabi kusa da ko a gaba. Manufofin daidaito na Faransa sun haifar da tattara malamai da yawa. Sun yi aiki a cikin rami kuma da yawa daga cikinsu sun rasa a lokacin yakin. Yana da ban mamaki cewa a lokacin hidimarsa a yaƙin, har yanzu ya sami nasarar samar da takardun lissafi masu kyau akai-akai, duk da cewa yana da ɗan lokaci kaɗan don ba da gudummawa ga lissafi.
Manazarta
[gyara sashe | gyara masomin]- ↑ Biographical Index of Former Fellows of the Royal Society of Edinburgh 1783–2002 (PDF). The Royal Society of Edinburgh. July 2006. ISBN 0-902-198-84-X. Archived from the original (PDF) on 24 January 2013. Retrieved 13 June 2016.