Louis Nirenberg

Louis Nirenberg (Fabrairu 28, 1925 - Janairu 26, 2020) masanin lissafi ne na Kanada-Amurka, wanda aka dauke shi daya daga cikin fitattun masu lissafi na karni na 20. 

Kusan dukkanin ayyukansa sun kasance a fagen ƙididdigar bambance-bambance. Yawancin gudummawar da ya bayar yanzu ana ɗaukar su a matsayin mahimmanci ga filin, kamar ƙa'idarsa mai ƙarfi don ƙididdigar bambancin bambancin tsari na biyu da kuma Newlander-Nirenberg theorem a cikin lissafi mai rikitarwa. An dauke shi a matsayin mutum mai tushe a fagen nazarin lissafi, tare da yawancin ayyukansa suna da alaƙa da nazarin bincike mai rikitarwa da bambancin lissafi.

 Tarihin rayuwa 
An haifi Nirenberg a Hamilton, Ontario ga baƙi Yahudawa na Ukraine. Ya halarci Makarantar Sakandare ta Baron Byng da Jami'ar McGill, inda ya kammala BS a fannin lissafi da kimiyyar lissafi a shekarar 1945. Ta hanyar aikin bazara a Majalisar Bincike ta Kasa ta Kanada, ya sadu da matar Ernest Courant Sara Paul. Ta yi magana da mahaifin Courant, sanannen masanin lissafi Richard Courant, don shawara game da inda Nirenberg ya kamata ya nemi don nazarin ilimin lissafi. Bayan tattaunawarsu, an gayyaci Nirenberg don shiga makarantar digiri a Cibiyar Courant ta Kimiyya ta Lissafi a Jami'ar New York. A shekara ta 1949, ya sami digirin digirinsa a lissafi, a karkashin jagorancin James Stoker . A cikin aikinsa na digiri, ya warware "matsalar Weyl" a cikin bambancin lissafi, wanda ya kasance sanannen matsala tun 1916.

Bayan digirin digirinsa, ya zama farfesa a Cibiyar Courant, inda ya kasance har zuwa sauran aikinsa. Ya kasance mai ba da shawara ga daliban PhD 45, kuma ya buga takardu sama da 150 tare da wasu marubuta, gami da haɗin gwiwa tare da Henri Berestycki, Haïm Brezis, Luis Caffarelli, da Yanyan Li, da sauransu da yawa. Ya ci gaba da gudanar da bincike na lissafi har zuwa shekara 87. A ranar 26 ga watan Janairun 2020, Nirenberg ya mutu yana da shekaru 94. Caffarelli, Luis A.; Li, YanYan. Preface [Dedicated to Louis Nirenberg on the occasion of his 85th birthday. Part I]. Discrete Contin. Dyn. Syst. 28 (2010), no. 2, i–ii. doi:10.3934/dcds.2010.28.2i 

An san aikin Nirenberg sosai, gami da kyaututtuka da girmamawa masu zuwa:

 Nasarorin lissafi 
Nirenberg an san shi musamman saboda hadin gwiwar da ya yi tare da Shmuel Agmon da Avron Douglis inda suka fadada Ka'idar Schauder, kamar yadda aka fahimta a baya don daidaitattun bambance-bambance na biyu, zuwa tsarin tsarin tsarin elliptic gaba ɗaya. Tare da Basilis Gidas da Wei-Ming Ni ya yi amfani da ka'idar mafi girma don tabbatar da daidaituwa na mafita da yawa na daidaitattun bambance-bambance. Nazarin sararin aikin BMO ya fara ne daga Nirenberg da Fritz John a cikin 1961; yayin da John ya gabatar da shi ne a cikin nazarin kayan sassauci, an kuma yi amfani da shi ga wasannin sa'a da aka sani da martingales.[1] Ayyukansa na 1982 tare da Luis Caffarelli da Robert Kohn sun ba da gudummawa sosai ga wanzuwar Navier-Stokes da santsi, a fagen injiniyan ruwa na lissafi.

Sauran nasarorin sun hada da warware Matsalar Minkowski a cikin nau'o'i biyu, rashin daidaito na Gagliardo-Nirenberg, Newlander-Nirenberg theorem a cikin lissafi mai rikitarwa, da ci gaban masu aiki daban-daban tare da Joseph Kohn.

 Manazarta 

Rukuni:Mutattun 2020
Rukuni:Haifaffun 1925
Rukuni:Shafuka masu fassarorin da ba'a duba ba