Mary Cartwright

**Dame Mary Lucy Cartwright** DBE FRS FRSE (17 Disamba 1900 - 3 Afrilu 1998)  ta kasance masanin lissafi na Burtaniya. Ta kasance ɗaya daga cikin masu gabatarwa na abin da daga baya za a san shi da Ka'idar rikici. Tare da J. E. Littlewood, Cartwright ya ga mafita da yawa ga matsalar da daga baya za a gani a matsayin misali na Tasirin malam buɗe ido.&nbsp;

## Rayuwa ta farko da ilimi

An haifi Mary Cartwright a ranar 17 ga Disamba 1900, a Aynho, Northamptonshire, inda mahaifinta William Digby ya kasance vicar. Ta hanyar kakarta Jane Holbech, ta fito ne daga mawaki John Donne da William Mompesson, Vicar na Eyam .  Tana da 'yan uwa huɗu, biyu babba da biyu ƙarami: John (an haife shi a shekara ta 1896), Nigel (an haifee a shekara ta 1895), Jane (an haifi a shekara ta 1905), da William (an haifa a shekara ta 1907).  Ta fara karatunta ne a makarantar sakandare ta Leamington (1912-1915), sannan kuma a makarantar Gravely Manor a Boscombe (1915-1916) kafin ta kammala a Makarantar Godolphin a Salisbury (1916-1919). 

Cartwright ta yi karatun lissafi a Kwalejin St Hugh, Oxford, ta kammala karatu a 1923 tare da digiri na farko. Ita ce mace ta farko da ta kai laccoci na karshe kuma ta sami na farko. Ta koyar da ɗan gajeren lokaci a Makarantar Alice Ottley a Worcester da Wycombe Abbey School a Buckinghamshire kafin ta koma Oxford a 1928 don karanta wa D.Phil. G. H. Hardy ne ke kula da Cartwright a cikin karatun digirin digirinsa. A lokacin shekara ta ilimi ta 1928-9 Hardy ya kasance a Princeton, don haka E. C. Titchmarsh ne ya ɗauki nauyin a matsayin mai kula. J. E. Littlewood ne ya bincika rubutunta "The Zeros of Integral Functions of Special Types", wanda ta sadu da shi a karo na farko a matsayin mai jarrabawa na waje a jarrabawar baki don wannan 1930 D.Phil.

A cikin 1930, an ba Cartwright kyautar Yarrow Research Fellowship kuma ta tafi Kwalejin Girton, Cambridge don ci gaba da aiki a kan batun takardar karatun digiri. Da ta halarci laccocin Littlewood, ta warware daya daga cikin matsalolin da ya gabatar. Ka'idar lissafinta, wanda yanzu aka sani da Ka'idar Cartwright, yana ba da ƙididdiga don matsakaicin modulus na aikin nazari wanda ke ɗaukar ƙimar ɗaya ba fiye da p sau a cikin faifan raka'a ba. Don tabbatar da ka'idar ta yi amfani da sabon tsarin, ta amfani da dabarar da Lars Ahlfors ya gabatar don taswirar da ta dace. Yayinda yake a Cambridge Cartwright ya halarci laccocin lissafi na Ludwig Wittgenstein . 

## Ayyuka
A cikin aikinta, Cartwright ta rubuta labarai sama da casa'in a kan ra'ayoyin lissafi daban-daban. Gudummawar da ta bayar ta kai ga batutuwa kamar jerin Dirichlet, jimlar Habila, jagororin Borel yada, ayyukan nazari na yau da kullun a kan faifan raka'a, zeros na ayyuka masu mahimmanci, matsakaicin da mafi ƙarancin tsari, da ayyuka na tsari mai iyaka a cikin kusurwa.

A shekara ta 1936, Cartwright ya zama darektan karatu a lissafi a Kwalejin Girton . A cikin 1938, ta fara aiki a kan sabon aikin da ya yi babban tasiri a kan jagorancin bincikenta. Kwamitin Binciken Rediyo na Ma'aikatar Binciken Kimiyya da Masana'antu ya samar da wata yarjejeniya game da wasu daidaitattun bambance-bambance waɗanda suka fito daga aikin rediyo da radar.[1] Sun tambayi London Mathematical Society idan za su iya taimakawa wajen samun masanin lissafi wanda zai iya aiki a kan waɗannan matsalolin kuma ta zama mai sha'awar. Matsayin da ke bayan matsalolin bai saba da Cartwright ba, don haka ta kusanci Littlewood don taimako tare da wannan bangare. Sun fara hadin gwiwa wajen nazarin daidaitattun, musamman ma Van der Pol oscillator, wanda ya ba su mamaki sosai:

## Manazarta