Manidh: 1 revision imported

2023-07-18T05:09:36Z

1 revision imported

← Older revision	Revision as of 10:39, 18 July 2023
(No difference)

wikipedia>Citation bot: Add: date. | Use this bot. Report bugs. | Suggested by Spinixster | Category:University of Bucharest alumni | #UCB_Category 524/603

2023-06-13T09:36:53Z

Add: date. | Use this bot. Report bugs. | Suggested by Spinixster | Category:University of Bucharest alumni | #UCB_Category 524/603

New page

{{short description|Romanian mathematician and poet}}
{{other people}}
{{Infobox person
| name = Ion Barbu
| image = Ion Barbu.jpg
| birth_name = Dan Barbilian
| birth_date = {{Birth date|1895|3|18}}
| birth_place = [[Câmpulung]], [[Kingdom of Romania]]
| death_date = {{Death date and age|1961|8|11|1895|3|18}}
| death_place = [[Bucharest]], [[Socialist Republic of Romania|Romanian People's Republic]]
| resting_place = [[Bellu Cemetery]], [[Sector 4 (Bucharest)|Sector 4]], [[Bucharest]], [[Romania]]
| nationality = [[Romanians|Romanian]]
| citizenship = {{plainlist|
* [[Kingdom of Romania]]
* [[Socialist Republic of Romania|Romanian People's Republic]]
}}
| education = {{plainlist|
* [[University of Groningen]]
* [[University of Tübingen]]
* [[Humboldt University of Berlin|University of Berlin]]
}}
| alma mater = [[University of Bucharest]] ([[Bachelor of Science|BS]] and [[Doctor of Philosophy|PhD]] in [[Mathematics]])
| occupation = {{plainlist|
* [[poet]]
* [[mathematician]]
}}
| years_active = 1919–1961
| era = [[Interwar period]]
| notable_works = Second game (Joc secund)
| movement = {{plainlist|
* [[Parnassianism]]
* [[Hermeticism]]
* [[Expressionism]]
}}
| spouse = Gerda Barbu
| mother = Smaranda Șoiculescu
| father = Constantin Barbilian
| module =
{{infobox scientist | embed=yes
| thesis_title = Canonical representation of the addition of hyperelliptic functions
| thesis_url =
| thesis_year = 1929
| doctoral_advisor = [[Gheorghe Țițeica]]
| academic_advisors =
| doctoral_students =
| notable_students =
| fields = Geometry
| workplaces = [[University of Bucharest]]
}}
}}
'''Ion Barbu''' ({{IPA-ro|iˈon ˈbarbu}}, [[pen name]] of '''Dan Barbilian'''; 18 March 1895 –11 August 1961) was a [[Romania]]n [[mathematician]] and [[poet]]. His name is associated with the [[Mathematics Subject Classification]] number 51C05, which is a major posthumous recognition reserved only to pioneers of investigations in an area of mathematical inquiry.<ref>{{cite web|url=https://mathscinet.ams.org/mathscinet/msc/msc2020.html?t=51Cxx|publisher=[[American Mathematical Society]]|title=MathSciNet: 51C05 (1980-now) Ring geometry (Hjelmslev, Barbilian, etc.)}}</ref>

==Early life==
Born in [[Câmpulung|Câmpulung-Muscel]], [[Argeș County]], he was the son of Constantin Barbilian and Smaranda, born Șoiculescu. He attended elementary school in Câmpulung, [[Dămienești]], and [[Stâlpeni]], and for secondary studies he went to the [[Ion Brătianu National College (Pitești)|Ion Brătianu High School]] in [[Pitești]], the [[Dinicu Golescu National College|Dinicu Golescu High School]] in Câmpulung, and finally the [[Gheorghe Lazăr National College (Bucharest)|Gheorghe Lazăr High School]] and the [[Mihai Viteazul National College (Bucharest)|Mihai Viteazul High School]] in [[Bucharest]].<ref>{{cite web|url=https://www.argesexpres.ro/index.php/cultura/32394-ion-barbu-dan-barbilian-poet-si-matematician-3|title=Ion Barbu/Dan Barbilian, poet și matematician|first=C.|last=Voiculesu|newspaper=Argeș Expres|date=March 23, 2020|access-date=May 9, 2021}}</ref> During that time, he discovered that he had a talent for mathematics, and started publishing in ''Gazeta Matematică''; it was also then that he discovered his passion for [[poetry]]. Barbu was known as "one of the greatest Romanian poets of the twentieth century and perhaps the greatest of all" according to Romanian literary critic Alexandru Ciorănescu.<ref>Alexandru Ciorănescu (1981) ''Ion Barbu'', [[Twayne]] Publishers, Boston, {{ISBN|0-8057-6432-1}}</ref> As a poet, he is known for his volume ''Joc secund'' ("Mirrored Play").<ref>[https://web.archive.org/web/20051217194821/http://www.ici.ro/romania/en/cultura/l_barbu.html Ion Barbu] from Intitutul Național de Cercetare, Romania.</ref>

He was a student at the [[University of Bucharest]] when [[World War I]] caused his studies to be interrupted by military service. He completed his degree in 1921. He then went to the [[University of Göttingen]] to study [[number theory]] with [[Edmund Landau]] for two years. Returning to Bucharest, he studied with [[Gheorghe Țițeica]], completing in 1929 his thesis, ''Canonical representation of the addition of hyperelliptic functions''.<ref>{{cite journal | last1 = Boskoff | first1 = Wladimir G. | last2 = Suceavă | first2 = Bogdan | year = 2007 | title = Barbilian spaces: the history of a geometric idea | journal = [[Historia Mathematica]] | volume = 34 | issue = 2| pages = 221–224 | doi = 10.1016/j.hm.2006.06.001 | doi-access = free }}</ref><ref>{{MathGenealogy|id=267122}}</ref>

==Achievements in mathematics==
===Apollonian metric===
In 1934, Barbilian published his article<ref>"Einordnung von Lobayschewskys Massenbestimmung in einer gewissen algemeinen Metrik der Jordansche Bereiche", ''Casopis Matematiky a Fysiky'' 64:182,3</ref> describing metrization of a region ''K'', the interior of a [[simple closed curve]] ''J''. Let ''xy'' denote the [[Euclidean distance]] from ''x'' to ''y''. Barbilian's function for the distance from ''a'' to ''b'' in ''K'' is
:<math>d(a,b) = \log \underset{p \in J}{\max} (pa/pb) + \log \underset{q \in J}{\max} (qb/qa) .</math>
At the [[University of Missouri]] in 1938 [[Leonard Blumenthal]] wrote ''Distance Geometry. A Study of the Development of Abstract Metrics'',<ref>University of Missouri Studies #13</ref> where he used the term "Barbilian spaces" for [[metric space]]s based on Barbilian's function to obtain their [[metric (mathematics)|metric]]. And in 1954 the [[American Mathematical Monthly]] published an article by [[Paul Kelly (mathematician)|Paul J. Kelly]] on Barbilian's method of metrizing a region bounded by a curve.<ref>[[Paul Kelly (mathematician)|Paul J. Kelly]] (1954) "Barbilian geometry and the Poincaré model", [[American Mathematical Monthly]] 61:311–19 {{doi|10.2307/2307467}} {{mr|id=0061397}}</ref> Barbilian claimed he did not have access to Kelly's publication, but he did read Blumenthal's review of it in [[Mathematical Reviews]] and he understood Kelly's construction. This motivated him to write in final form a series of four papers, which appeared after 1958, where the metric geometry of the spaces that today bears his name is investigated thoroughly.

He answered in 1959 with an article<ref>Dan Barbilian, "Asupra unui principiu de metrizare", ''Academia Republicii Populare Romîne. Studii și Cercetări Matematice'' '''10''' (1959), 69–116. {{MR|0107848}}</ref> which described "a very general procedure of metrization through which the positive functions of two points, on certain sets, can be refined to a distance." Besides Blumenthal and Kelly, articles on "Barbilian spaces" have appeared in the 1990s from Patricia Souza, while Wladimir G. Boskoff, Marian G. Ciucă and [[Bogdan Suceavă]] wrote in the 2000s about "Barbilian's metrization procedure".<ref>{{citation|url=https://link.springer.com/article/10.1007%2Fs10587-008-0068-x |last1=Boskoff|first1=Wladimir G.|last2= Suceavă|first2= Bogdan D.|author2-link=Bogdan Suceavă|title= Barbilian's metrization procedure in the plane yields either Riemannian or Lagrange generalized metrics|journal= Czechoslovak Mathematical Journal |volume=58|pages= 1059–1068 |year=2008|issue=4|doi=10.1007/s10587-008-0068-x|hdl=10338.dmlcz/140439|hdl-access=free|mr=2471165|s2cid=54742376}}</ref> Barbilian indicated in his paper ''Asupra unui principiu de metrizare'' that he preferred the term "[[Apollonius of Perga|Apollonian]] metric space", and articles from [[Alan F. Beardon]], [[Frederick Gehring]] and [[Kari Hag]], Peter A. Häströ, Zair Ibragimov and others use that term. According to Suceavă,<ref>{{citation|first=Bogdan|last= Suceavă|title= Distances generated by Barbilian's metrization procedure by oscillation of sublogarithmic functions|journal= Houston Journal of Mathematics|volume=37| year=2011|pages= 147–159|citeseerx=10.1.1.433.7757|mr=2786550}}</ref> "Barbilian's metrization procedure is important for at least three reasons: (1) It yields a natural generalization of Poincaré and Beltrami-Klein's hyperbolic geometries; (2) It has been studied in the context of the study of Apollonian metric; (3) Provides a large class of examples of Lagrange generalized metrics irreducible to Riemann, Finsler, or Lagrange metrics."

===Ring geometry===
Barbilian made a contribution to the [[Foundations of mathematics#Projective geometry|foundations of geometry]] with his articles in 1940 and 1941 in [[Jahresbericht der Deutschen Mathematiker-Vereinigung]] on [[projective plane]]s with coordinates from a [[ring (mathematics)|ring]].<ref>D. Barbilian (1940,1) "Zur Axiomatik der projecktiven ebenen Ringgeometrien" I,II, [[Jahresbericht der Deutschen Mathematiker-Vereinigung]] 50:179–229 {{MathSciNet|id=0003710}}, 51:34–76, {{MathSciNet|id=0005628}}</ref><ref>{{cite journal | last1 = Kvirikashvili | first1 = T.G. | year = 2008 | title = Projective geometries over rings and modular lattices | journal = Journal of Mathematical Sciences | volume = 153 | issue = 4 | pages = 495–505 | doi = 10.1007/s10958-008-9133-0 |mr=2731947| s2cid = 120567853 }}</ref> According to Boskoff and Suceavă, this work "inspired research in ring geometries, nowadays associated with his, Hjelmslev's and [[Wilhelm Klingenberg|Klingenberg]]'s names."
A more critical stance was taken in 1995 by Ferdinand D. Velkamp:
:A systematic study of projective planes over large classes of associative rings was initiated by D. Barbilian. His very general approach in [1940 and 41] remained rather unsatisfactory, however, his axioms were partly of a geometric nature, partly algebraic as pertaining to the ring of coordinates, and there were a number of difficulties which Barbilian could not overcome.<ref>{{cite journal| doi=10.1016/B978-044488355-1/50021-9 | title=Geometry over Rings | year=1995 | journal=Handbook of Incidence Geometry | pages=1033–1084 | last1 = Veldkamp | first1 = Ferdinand D. | mr = 2320101|isbn=978-0-444-88355-1 }}</ref>
Nevertheless, in 1989 John R. Faulkner wrote an article "Barbilian Planes"<ref>{{cite journal | last1 = Faulkner | first1 = John R. | year = 1989 | title = Barbilian Planes | journal = [[Geometriae Dedicata]] | volume = 30 | issue = 2| pages = 125–81 |mr=1000255 | doi=10.1007/bf00181549| s2cid = 189890461 }}</ref> that clarified terminology and advanced the study. In his introduction, he wrote:
:A classical result from projective geometry is that a [[Girard Desargues|Desarguesian]] projective plane is coordinatized by an associative [[division ring]]. A Barbilian plane is a geometric structure which extends the notion of a projective plane and thereby allows a coordinate ring which is not necessarily a division ring. There are advantages ...

===Works===
* 1956: {{lang|ro|"Teoria aritmetică a idealelor (în inele necomutative)", ''Editura Academiei Republicii Populare Romîne'' |italic=unset}}, Bucharest. {{MR|0085247}}
* 1960: {{lang|ro|"Grupuri cu operatori: Teoremele de descompunere ale algebrei", ''Editura Academiei Republicii Popular Romîne'' |italic=unset}}, Bucharest. {{MR|0125888}}

==Academic career==
In 1942, Barbilian was named professor at the [[University of Bucharest]], with some help from fellow mathematician [[Grigore Moisil]].<ref>O'Connor, John J; Edmund F. Robertson, [http://www-history.mcs.st-andrews.ac.uk/Biographies/Moisil.html "Grigore C. Moisil"], ''[[MacTutor History of Mathematics archive]]''</ref>

As a mathematician, Barbilian authored 80 research papers and studies. His last paper, written in collaboration with Nicolae Radu, appeared posthumously, in 1962, and is the last in the cycle of four works where he investigates the Apollonian metric.

==Political creed==
Barbu was mostly apolitical, with one exception: around 1940 he became a sympathizer of the fascist movement [[The Iron Guard]] (hoping to get a professorship if they came to power), dedicating some poems to one of its leaders, [[Corneliu Zelea Codreanu]]. In 1940, he also wrote a poem praising [[Hitler]].<ref>{{cite web|url=http://www.romaniaculturala.ro/articol.php?cod=100|title=Căderea poetului|publisher=[[România Literară]]|language=ro|access-date=August 30, 2013|archive-url=https://web.archive.org/web/20140429185030/http://www.romaniaculturala.ro/articol.php?cod=100|archive-date=April 29, 2014}}</ref><ref>{{cite web|url=http://adevarul.ro/cultura/istorie/riga-crypto-drogurile-legionarii-1_50ba02487c42d5a663af8f9a/index.html|title=Riga Crypto, drogurile şi legionarii|date=18 June 2011 |publisher=[[Adevarul]]|language=ro|access-date=August 30, 2013}}</ref>

==Death and legacy==
[[File:Bellu 130222 67.jpg|thumb|Grave in [[Bellu Cemetery]]]]
[[File:Casa pe Str. Carol Davila nr. 8 (Casa Ion Barbu) Bucuresti sect. 5 (detaliu 2).JPG|thumb|Commemorative plaque affixed on Barbu's house by the Bucharest City Hall in 1991]]
Ion Barbu died in [[Bucharest]] in 1961, and is buried at [[Bellu Cemetery]].

The [[Ion Barbu Theoretical High School]] in [[Pitești]], the [[Ion Barbu Technological High School]] in [[Giurgiu]], and the [[Dan Barbilian Theoretical High School]] in [[Câmpulung]] are all named after him.

== Presence in English language anthologies ==
* ''Born in Utopia - An anthology of Modern and Contemporary Romanian Poetry -'' Carmen Firan and Paul Doru Mugur (editors) with Edward Foster - Talisman House Publishers - 2006 - {{ISBN|1-58498-050-8}}
* ''Testament - Anthology of Romanian Verse - American Edition -'' monolingual English language edition - [[Daniel Ioniță (poet)|Daniel Ioniță]] (editor and principal translator) with Eva Foster, Daniel Reynaud and Rochelle Bews - Australian-Romanian Academy for Culture - 2017 - {{ISBN|978-0-9953502-0-5}}
* T''estment – 400 Years of Romanian Poetry – 400 de ani de poezie românească'' – bilingual edition – [[Daniel Ioniță (poet)|Daniel Ioniță]] (editor and principal translator) with [[Daniel Reynaud]], Adriana Paul & Eva Foster – Editura Minerva, 2019 – {{ISBN|978-973-21-1070-6}}
* ''Romanian Poetry from its Origins to the Present'' – bilingual edition English/Romanian – [[Daniel Ioniță (poet)|Daniel Ioniță]] (editor and principal translator) with [[Daniel Reynaud]], Adriana Paul and Eva Foster – Australian-Romanian Academy Publishing – 2020 – {{ISBN|978-0-9953502-8-1}} ; {{OCLC|1288167046}}

==References==
{{Reflist}}

{{Romanian modernist literature in World War II}}
{{Authority control}}

{{DEFAULTSORT:Barbu, Ion}}
[[Category:1895 births]]
[[Category:1961 deaths]]
[[Category:People from Câmpulung]]
[[Category:Gheorghe Lazăr National College (Bucharest) alumni]]
[[Category:University of Bucharest alumni]]
[[Category:Academic staff of the University of Bucharest]]
[[Category:Romanian avant-garde]]
[[Category:Romanian male poets]]
[[Category:20th-century Romanian inventors]]
[[Category:Romanian textbook writers]]
[[Category:20th-century Romanian mathematicians]]
[[Category:20th-century Romanian poets]]
[[Category:20th-century Romanian male writers]]
[[Category:Pseudonymous mathematicians]]
[[Category:Members of the Romanian Academy elected posthumously]]
[[Category:Members of the Romanian Academy of Sciences]]
[[Category:Burials at Bellu Cemetery]]
[[Category:Geometers]]
[[Category:20th-century pseudonymous writers]]

Ion Barbu - Revision history

Manidh: 1 revision imported

wikipedia>Citation bot: Add: date. | Use this bot. Report bugs. | Suggested by Spinixster | Category:University of Bucharest alumni | #UCB_Category 524/603