William Feller (1906-1970)
Darko Zubrinic, 2006 [in Croatian]
Extemded summary. William Feller (Zagreb, July 7th, 1906 - New York, January 14th, 1970), outstanding Croatian - American mathematician, born in Croatia as Vilibald Srecko Feller. As a student he simplified the name to Vilim. At the University of Zagreb studied mathematics for the first two years (i.e. the first four semesters out of eight, 1923-1925), and then continued his studies in Göttingen where he earned his doctorate in 1926 under Richard Courant. He prepared a part of his thesis already as a student in Zagreb. Professor in Kiel (Germany, 1928-1933), Copenhagen (Denmark, 1933-1934), Stockholm, and Lund (Sweden, 1934-1939). In 1938 he married Clara Nielsen.
Since 1939 lived in the USA, employed at Universities of Brown, Cornell, and since 1950 at Princeton University as a Eugen Higgins Professor of mathematics. Feller wrote the review of A.N. Kolmogorov's famous book Grundbegriffe der Wahrscheinlichkeitsrechnung (Foundations of Probability Theory) for Zentralblatt für Mathematik in 1934. One of initiators of editing Mathematical Reviews (1939), and one of its first executive directors (1944-1945). One of the founders of Probability Theory as a scientific discipline, best known for his two volume monograph An Introduction to Probability Theory and Its Applications, which is considered as one of the finest mathematical textbooks of the 20th century. It was translated into Russian (with foreword to Volume 1 written by Kolmogorov), Chinese, Castellano, Polish, and Hungarian. About hundred and fifty mathematical notions bear his name: Feller process, Feller transition function, Feller semigroup, Feller's property, Feller Brownian motions, Feller's test for explosions, Lindeberg-Feller condition, Feller operator, Feller potential, Feller measures, indefinite Krein-Feller differential operators, Kolmogorov-Feller equation, etc.
At the International Congress of Mathematicians held in 1958 in Edinburgh, Feller delivered a plenary talk "Some new connections between probability and classical analysis." In 1966 he was elected to the international scientific committee which had to choose candidates for the 1966 Fields Medal at the International Congress of Mathematicians in Moscow. Feller had 17 PhD students. Member of several national academies: former Yugoslav (since 1990 Croatian) Academy of Sciences and Arts in Zagreb, Royal Danish Academy of Sciences, National Academy of Sciences (USA), American Academy of Arts and Sciences, Boston, and of prestigeous scientific organizations: Royal Statistical Society, London, and The London Mathematical Society (honorary member). Recipient of the 1969 National Medal of Science by the president of the USA (posthumously in 1970). An asteroid was named after him in 1996: 21276 Feller (1996 TF5).
On July 17th 1953 William Feller delivered a lecture in Zagreb in Croatian language, under the title "Matematicka teorija difuzije" (Mathematical theory of diffusion). He was in touch with his relatives in Zagreb, as well as with his colleagues at the University of Zagreb. During the post WWII period Feller visited Zagreb on four occasions: in 1953, 1956, 1957 and 1958. According to Vladimir Vranić, professor of mathematics at the University of Zagreb and a personal friend of Feller, "not only that Vilim Feller did not hide his Croatian descent, but he was also proud of it."
William Feller – version française abrégé
William Feller (né à Zagreb le 7 juillet 1906, mort à New York le 14 janvier 1970) fut un mathématicien distingué. Ses prénoms de baptême furent Vilibald, Srećko et ce n’est qu’en rentrant à l’université qu’il raccourcît ses prénoms en Vilim. Après deux ans d’études des mathématiques à l’université de Zagreb il continua à l’université de Göttingen où il obtint le doctorat ès mathématiques en 1926 (à l’âge de 22 ans !) sous la direction de Richard Currant. William rédigea certaines parties de sa thèse de doctorat pendant ses études à Zagreb.
Il fut professeur à Kiel en Allemagne (1928-1933), Copenhague en Danemark (1933-1934), Stockholm et Lund en Suède (1934-1939). En 1939 il épousa Clara Nielsen. Puis en 1939 il s’installa aux Etats Unis où il enseigna aux universités Brown, Cornel et en 1950 à l’université de Princeton.
En 1934 Feller a écrit pour Zentralblatt für Mathematik la revue de fameux Grundbegriffeder Wahrscheinlichkeitsrechnung (Les Bases de la Théorie de Probabilité) d’A.N. Kolmogorov.
En 1939 il était un des fondateurs de «Mathematical Reviews» et entre 1944 et 1945 il en devint le directeur exécutif.
En tant qu’un des fondateurs de la théorie de probabilité moderne comme une discipline scientifique il est le plus connu par son œuvre en deux volumes «An Introduction to Probability Theory And Its Application». Cette monographie est considérée parmi les textes mathématiques les plus remarquables de 20eme siècle. Elle a été traduite en Russe (avec l’avant-propos au premier volume écrit par Kolmogorov), Chinois, Espagnol, Polonais et Hongrois.
Il existe environ 150 références qui portent le nom de Feller : Le Processus Feller, La fonction de transition Feller, Le Semi-group de Feller, la propriété de Feller, les mouvements Feller- Brown, le test d’explosion Feller, la condition Lindenberg – Feller, l’operateur Feller, le potentiel Feller, les mesures Feller, les opérateurs différentiels indéfini de Krein-Feller, L’équation de Kolmogorov-Feller etc.
Au congrès international des mathématiciens à Edinburgh en 1958 Feller a présenté un discours plénière «Quelques connections nouvelles entre la probabilité et l’analyse classique» (Some new connections between probability and classical analysis).
Au congrès international des mathématiciens qui a eu lieu en 1966 à Moscou il a été élu membre de comité scientifique international pour l’élection des candidats pour la médaille «Fields». Feller a proposé 17 étudiants préparant leur thèse de doctorat.
Il a été membre de plusieurs Académies nationales : L’ex Yougoslave (maintenant Croate) Académie des Sciences et Arts à Zagreb, L’Académie royale des sciences de Danemark, L’Académie Nationale des Sciences des Etats Unis, L’Académie américaine des arts et sciences à Boston. Aussi a-t-il été le membre de plusieurs autres organisations scientifiques prestigieuses telles que La Société royale des statistiques à Londres, La Société des mathématiciens de Londres (membre honoraire).
A titre posthume en 1970 il a reçu du président des Etats Unis la médaille des Sciences pour l’année 1969. En 1996 un astéroïde (21276 Feller – 1996 TF5) a été nommé à son honneur.
Le 17 juillet 1953 William Feller a présenté à Zagreb une conférence en langue croate sous le titre : «La théorie mathématique de diffusion».
Il garda toujours le contact avec sa famille et ses collègues de l’Université de Zagreb. Après la seconde guerre mondiale Feller s’est rendu à Zagreb quatre fois : en 1953, 1956, 1957 et 1958.
Selon Vladimir Vranić, le professeur des mathématiques à l’Université de Zagreb, «non seulement William Feller ne cacha ses origines Croates mais il en fut fier»
J. Dieudonné, le mathématicien français de renommé et membre du groupe Bourbaki dans son livre «Le Panorama des Mathématiques Pures – Vu Par N. Bourbaki» (Academic Press, New York, London 1982) nota que les bases principales de la théorie de probabilité sont liées aux noms suivants : J. Bernoulli (1654-1705), A. de Moivre (1667-1754), P. Laplace (1749-1827), D. Poisson (1781-1840), P. Čebišev (1821-1894), A. Markov (1856-1922), E. Borel (1871-1956), N. Wiener (1894-1959), P. Lévy (1886-1971), A. Kolmogorov (1903-1987), A. Hinčin (1894-1959). W. Feller (1906-1970), J. Doob (1910-2004) et G. Hunt (n. 1916).
Traduit du croate par Nikola Zdenković.
By the end 2011 the following monograph about William Feller has been published as a bilingual, Croatian-English edition:
Darko Žubrinić: William Feller - Distinguished Croatian-American Mathematician, Graphis, Zagreb 2011
The book is accompanied with 109 photos, printed on 140 pp, hardcover.
Contact. The book can be ordered using at the Graphis publisher in Zagreb:
tel. +385 1 2322 975
Preface, Summary and Extended Summary, p vii-xii
1. Origins and Youth of William Feller, p 1
2. In Germany and Scandinavia, p 31
3. Arrival to the USA, p 41
4. Feller's Monograph, p 53
5. The Importance of Feller's Scientific Work, p 73
6. Remembering William Feller, p 95
7. Echo of Feller's Opus in the Monograph Literature, p 107
8. An Illustration of Feller's Way of Writing, p 117
9. The Feller's Family Vault on the Mirogoj Graveyard in Zagreb, p 121
Literature (37 titles), p 125
List of 109 Photographs, p 129
Index, p 133
Predstavljanje knjige na Fakultetu elektrotehnike i računarstva Sveučilišta u Zagrebu 2012.
Vilim Feller was a son of world's famous pharmacist Eugen Viktor Feller (Lviv, Lamberg 1871 - Zagreb 1936), who built the family house with pharmacy and laboratories (on the photo below) and the farmaceutical factory, both in Donja Stubica near Zagreb in 1901.
His father initiated the industrial production of Elsa fluid and its variants (soaps, shampoos, shaving creams, balsams, hygienic and cosmetic products, elixirs, etc.), which was a world wide success, sold in the whole of Europe, Asia (Japan and China), Africa (Egypt), and in the USA. See [Fatovic-Ferencic and Ferber-Bogdan] for more information.
Eugen Viktor Feller, Vilim's
Eugen Viktor Feller married Ida Oehmichen (1870-1938; Oemichen is her father's second name, and her mother's second name is Pelc or Peltz), of Austrian descent, with whom he had twelve children, among them Vilim Feller. Eugen Viktor's father was David Feller, of Jewish descent, who lived first in Lviv (or Lavov, Lemberg), and then moved to Austria-Hungary, while his mother was Elizabeta (Elsa) Holzer, of Austrian descent. We may note that Viktor Eugen gave the name of Elsa fluid in honour of his beloved mother Elsa.
The family of Eugen Viktor Feller contributed to the urban shaping of the city of Zagreb by building three important houses:
The house of Feller's at
Tomislavov trg 4,
Zagreb, built in 1904, by H
Vilim Feller was born on 7 July, 1906 in Zagreb, in time of greatest prosperity of the family. His parents gave him the name of Vilibald Srecko Feller (the Croatian name Srecko is Felix in English). This can be seen in the register of births, Ilica 25, Zagreb (many thanks to prof. Marta Zdenkovic for this information). His address is indicated at Jurisiceva 1, that is, at Elsa fluid dom. The name of Vilibald was given to him according to St Vilibald, ie. St. Willibald, whose feastday is on 7 July. See more information about Sv. Vilibald in Croatian.
He was baptised on 19th July, 1906 in the church of St. Marko in the Upper Town in Zagreb, by rev. Petar Mrzljak. His godparents were Dr. Miroslav Müller, a physician in the town of Osijek, and his wife Marija. Entering the University of Zagreb in 1923 he changed his name to Vilim Feller.
He was the youngest one of eight brothers, and he also had four sisters (three sisters were born after him):
The huge and hard working family lived happily in Jurjevska 31a, Zagreb, in a beautifully organized house. It was projected by Viktor Eugen's half-brother Mathias Feller, an architect from Munich, Germany. It is interesting that this family building, surrounded with a cultivated park and rare plants, had among others an oval room for music and concerts (Musik-Zimmer). Today the house and the park are in a sad shape, devastated since 1945 during the ex-Yugoslav Communist period.
Vilibald Srecko Feller (bottom
youngest among eight brothers:
When young Vilibald Srecko Feller was at the age of a secondary school pupil, as a gifted child he had regular private lessons in mathematics from dr. Stanko Vlögel, professor of mathematics and engineering mechanics at the University of Zagreb.
I express my sincere gratitude to dr. Mirna Flögel-Mrsic, professor of biochemistry at the University of Zagreb, for this information (2006). Late professor Stanko Vlögel was her uncle.
Feller finished his secondary schooling in 1923 at the First Gymnasium in Zagreb. He had private lessons, and went to annual exams to that gymansium.
Feller enrolled for the study of mathematics at the University of Zagreb in the academic year 1923/1924. Here is the Matriculation Form issued by the University of Zagreb in 1925, during the second year of his studies of mathematics in Zagreb (during the second semester of the academic year1924/1925), published in [Science in Croatia 2, p. 109]. We underline the fact that the regular study of mathematics lasted for four years. Having completed his studies of mathematics in Zagreb in just two years, Feller continued at the University of Göttingen in Germany. According to the obituary published in [The Annals of Math. Statistics], Feller finished his studies at the University of Zagreb with a degree equivalent to today's Master of Science!
The content of the 1925 Matriculation Form, filled in by Vilim Feller personally, is as follows:Matriculation Form
Now there comes the list of lectures that he attended, with the coresponding names of the lecturers:
As we see, young Feller had altogether 29 working hours of lectures weekly (5 days), that is, at the pace of nearly 6 hours each working day.
A few words about Feller's professors in Zagreb. It is to be noted Dr. Vladimir Varicak at that time was already an established scientist of international reputation, one of the leading European specialists in Einstein's theory of relativity. His very much cited book "Darstellung der Relativitätstheorie im dreidimensionalen Lobatschefskijschen Raume" had been published in Zagreb in 1924 (follow the link for more information), when Feller was on the first year of study of mathematics in Zagreb. Also Stanko Hondl was known as an excellent professor of physics, whose lectures had strong emphasis on concrete experiments.
Dr. Hondl was a successor of professor Vinko Dvorzak, outstanding Czech physicist (and a student of Ernst Mach), who founded the study of physics at the University of Zagreb in 1875. It is very probable that Feller also attanded Hondl's special courses on the theory of relativity and atomic physics, as well as at other professors. Hondl spent an academic year specializing in physics in Göttingen and Berlin (1894-1896), where he also attended lectures delivered by Max Planck. It is very probable that Hondl wrote a recommendation letter for Feller to continue his studies in Göttingen. We mention that also Marije Kiseljak, who lectured Calculus, spent the academic year 1913/14 in Göttingen [Glasnik Mat. Fiz. Astr., 2, 1947, p. 205-209].
founded in 1669, where Feller studied from 1923 till 1925
Feller's professor Stjepan Bohnicek was a specialist in number theory. He studied mathematics and physics in Vienna, and published among others an extensive paper of almost 60 pages in Mathematische Annalen (Zur Theorie des relativbiquadratischen Zahlkörper, Mathematische Annalen, 63 (1906), 85-144). All this shows that young Feller had good professors, and obtained a solid grounding in mathematics and physics during his studies in Zagreb, which resulted with an equivalent of the title of Master of Science at the very young age of 19.
Here are two more matriculation forms filled in by Vilim Feller (2nd and 3rd semsester, University of Zagreb, 1924 and 1925):
In [Science in Croatia 2, p. 109], in an article by Academician Sibe Mardesic, we can see the names of some other lectures, including mathematical, attended by Feller during the first three semesters (we also exploited the data from the above two matriculation forms; many thanks to Professor Sibe Mardesic):
A very condensed Repetitorium of Differential and Integral Calculus (in Croatian) by Dr. Marije Kiseljak, 1925, from which the program of Mathematical Analysis for students of mathematics at the University of Zagreb could be seen in time when Feller was a student
But young Vilim Feller needed much stronger scientific environment. In 1925, after two years of study of mathematics in Zagreb, Feller entered the University of Göttingen, the strongest mathematical center in the world at that time. It is natural to assume that this happened under the advice (and recommendation) of his professors in Zagreb. Already the next year, in 1926 (November 3rd), he defended his doctoral thesis Über algebraisch rektifizierbare transzendente Kurven under the name of Willy Feller, at the age of only 20 years, and suma cum laude. His adviser was a famous mathematician Richard Courant, who was a student of David Hilbert. He remained in Göttingen for two years as an assistant of professor Courant. Feller became acquainted with David Hilbert, one of the greatest mathematicians of all times, who was also teaching there. Hilbert was always his ideal mathematician.
The archive of the University of Göttingen holds a file about the doctorate of Willy Feller in 1927 (Math.Nat.Prom. 0010, 23). The Faculty of Mathematics and Natural Sciences awarded him a PhD the July 18, 1927 in the disciplines of Mathematics, Analysis and Physics with the above mentioned thesis Über algebraisch rektifizierbare transzendente Kurven (review: Courant). As we have said, in November 3, 1926, the oral exam was held, and members of the committee were R. Courant, G. Herglotz and J. Franck. I express my deep gratitude to Dr. Ulrich Hunger from the Universitätsarchiv Göttingen for this information.
The thesis was published under the same title in Mathematische Zeitschrift in 1928, Vol 27, pp. 481-495.
According to [Vranic, p. 348], Feller already began his scientific work as a student of mathematics in Zagreb, which resulted with the above thesis defended in Göttingen. He reported his original results at the Geometric Seminar led by his professor Marije Kiseljak, Zagreb, who inspired young Feller's interest in this topic. As we have already mentioned, Feller completed his studies of mathematics in Zagreb with the title equivalent to today's Master of Science.
According to [Reid, Courant in Göttingen, p 111], the assistants of Richard Courant who supervised the mathematical Praktikum in Göttingen discovered at the beginning term in 1925 that there was no longer any need for them to solve problems themselves, since they discovered that the answers of Feller, a new student, were invariably correct.
Feller's first scientific work in the domain of Probability Theory was published in 1935 in Mathematische Zeischrift no 40, "Über den Grenzwertsatz der Wahrscheinlichkeitsrechnung, I", at the age of 29.
It seems to be little known that William Feller wrote a review of the famous book by outstanding Russian mathematician A.N. Kolmogorov (1903-1987), Grundbegriffe der Wahrscheinlichkeitsrechnung [English translation of the book], 1933, in which theoretical foundations of Probability Theory have been laid down:
Here is a part of Feller's review of Kolmogrov's Grundbegriffe for Zentrablatt, taken from [Shaffer and Vovk, p. 56]:
It is to be noted that Feller was only 27 years old when this book was published, while Kolmogorov was 30. We need to mention that there exists the Kolmogorov–Feller Equation in Probability Theory. Also, Kolmogorov wrote Foreword to the second Russian edition of Volume I of Feller's famous book An Introduction to Probability Theory and Its Applications.
According to a Swedish mathematician Ulf Grenander (in his interview published in Statistical Science),
Cramer certainly had impact on Feller, but as we saw, Feller published his first work on probability already in 1935, and Feller was very well acquainted with Kolmogorov's classic monograph, which he reviewd for Zentralblatt. Also, according to Professor Ulrich Krengel, Feller started his work in probability theory already in Kiel, that is, in 1933 at the latest.
Feller defended his habilitation thesis in 1928, and obtained the position of Privat Dozent in Kiel. According to [Croatian Biographical Lexicon] Feller was also a director of the Institute of Applied Mathematics at the University of Kiel. He remained in Kiel until 1933, when he left Germany due to the arrival of Nazism, refusing to sign the Nazi oath. He then continued his carreer in Copenhagen (working at the Mathematical Institute there from 1933 to 1934, where he met also Niels Bohr), and in Stockholm and Lund (from 1934 to 1939; among his colleagues there were Harald Cramér and Marcel Riesz). In 1938 he married Clara Nielsen, who had been his student already in Kiel. In 1939 Feller's emigrated to the USA.
In 1937 William Feller participated the celebrated colloquim on probability theory at the University of Geneva, chaired by Maurice Frechét. Feller's paper "Sur les axiomatiques du calcul des probabilités et leurs relations avec les expériences" was published in Wavre (1938–1939), pages 7–21 of the second fascicle, number 735 of Les fondaments du calcul des probabilités. Participants included Cramer, Dœblin, Feller, de Finetti, Heisenberg, Hopf, Levy, Neyman, Polya, Steinhaus, and Wald, and communications were received from Bernstein, Cantelli, Glivenko, Jordan, Kolmogorov, von Mises, and Slutsky. The proceedings were published by Hermann in eight fascicles in their series Actualites Scientifiques et Industrielles. The first seven fascicles appeared in 1938 as numbers 734 through 740. For more information see [Shaffer, Vovk].
According to personal information I obtained from Marta and Nikola Zdenkovic in 2006, Zagreb (their grandfather Ferdinand was William Feller's brother), William Feller was on friendly terms with Albert Einstein (1879-1955), despite a difference of almost 30 years. Since 1950, they were both in Princeton, USA: Einstein at the Institute of Advanced Study and Feller at the Princeton University.
In 1939 Feller became associate professor at Brown University (Providence, Rhode Island), and there he started his work on issuing Mathematical Reviews. This important reviewing math journal, now leading in the world, has been founded by the AMS (American Mathematical Society), with Neugebauer, Tamarkin and Feller as effective editorial staff (see [Rosenblatt, p. 5]).
In 1944 he became citizen of the USA. In 1945 Feller became a professor at Cornell University, where he worked for five years. In 1950 he obtained the position of Eugene Higgins Professor of Mathematics at Princeton, where he remained until his death in 1970. During the academic years 1965/66 and 1967/68 he lectured as a visiting professor at the Rockfeller University in New York.
It is interesting that Feller published two of his scientific works in a Croatian journal, Rad JAZU (JAZU = the then Yugoslav Academy of Sciences and Arts, Zagreb, since 1991 HAZU = Croatian Academy of Sciences and Arts). He wrote both articles in the Croatian language:
Under the title of the first article his name is written as follows:
Meanwhile, in 1937 he was elected as corresponding member of JAZU (now Croatian Academy of Sciences and Arts). This is indicated under the title of the second article, where his name is written as
We provide an excerpt from an article by an American mathematician Michael Golomb, Terror and Exile and a Letter About it (A report from Volume 4, #1, of TopCom), which was a part of a special exhibition organized during the International Congress of Mathematicians in Berlin, 1998:
Michael Golomb himself left Germany in 1933, went to the Croatian capital Zagreb, and in 1939 arrived to the USA.
Professor Ulrich Krengel from the University of Göttingen wrote the following about Feller's participation at International Mathematical Congresses, [History of Probability and Statistics at the International Congresses of Mathematicians, PS]:
At the International Congress of Mathematicians (ICM) held in Edinburgh 1958, William Feller delivered one hour plenary talk "Some new connections between probability and classical analysis", [PDF, 6.8 MB]. For more detailed information see History of Probability and Statistics at the International Congresses of Mathematicians, [PS], by Ulrich Krengel, University of Göttingen, Germany.
Feller was among those who initiated publishing the important Mathematical Reviews journal in 1939, and was one of its first executive editors (1944-1945; the first editors were Otto Neugebauer, 1939-1940, and J.D. Tamarkin, 1940-1944).
Now Mathematical Reviews are published on the web:
According to Ulf Grenander (in his very interesting interview published in Statistical Science), Feller had been the editor of Mathematische Zentralblatt. When he arrived from Stockholm to Brown University (USA) in 1939, he had a complete list of active mathematicians from all over the world with him, and that number at that time was 300! Furthermore,
According to the [Annals of Math. Statistics, 1970],
William Feller's monograph An Introduction to Probability Theory and its Applications, Volumes I and II (the first edition appeared in 1950, when Feller was 44), it had subsequent editions, and was translated into several other languages (Russian, Chinese, Polish, Spanish, and Hungarian). It is considered to be one of the best mathematical textbooks written in the 20th century. According to Feller's own words, he worked on Volume I for eight years, since 1941 till 1948.
William Feller: An Introduction to Probability Theory and its Applications, Volume one, John Wiley, New York, 1950
A few quotations from the book:
We provide an excerpt from the review of the 1950 first edition of Feller's book (Volume I), written for Mathematical Reviews by R. Fortet:
From the review of the 1957 second edition of Feller's book (Volume I), written by U. Grenander for Mathematical Reviews:
From the review of the 1966 first edition of Feller's book (Part II), written by S. Orey for Mathematical Reviews:
As we have said, Feller worked eight years on preparing Volume I of the first edition of his monograph, issued in 1950 (xii+419 pp).
The second volume appeared sixteen years later, in 1966 (xviii+636 pp). Both volumes comprise altogether 1135 pages. Volume I had two more editions, in 1957 (xv+461 pp) and in 1968 (xviii + 509 pp). Both of them were substantially improved with respect to previous editions.
In the Preface to the Volume II of his book, published in 1966, Feller wrote the following:
Here are the data about the latest editions of both Volumes (from MathSciNet), which comprise altogether 1178 pp:
The second edition of Volume II was issued in 1971, soon after Feller's death in the Memorial Hospital in New York, January 14, 1970, at the age of 63. His wife Clara wrote on p. xi of the book the following lines:
See the contents of Volume II of Feller's monograph on Probability Theory.
As we have said, his books have been translated into Russian, Chinese, Polish, Spanish and Hungarian. The first Russian translation of Volume I appeared just a year after the appearance of the book in 1950! And also the first Russian translation of Volume II appeared just a year after the appearance of the book in 1966! Moreover, Feller himself provided corrections of the English 1966 edition for the 1967 Russian edition of Volume II! Here is more detailed information based on Mathematical Reviews:
Feller, V. Vvedenie v teoriyu veroyatnostei i eë prilozeniya. (Diskretnye raspredeleniya.) (Russian) [An introduction to probability theory and its applications. (Discrete distributions.)] Izdat. Inostrannoj Literatury, Moscow, 1951. 427 pp.
Feller, V.: Vvedenie v teoriyu veroyatnostej i ee prilozheniya. Tom 1. (Russian) [An introduction to probability theory and its applications. Vol. 1] Translated from the English by R. L. Dobrusin, A. A. Juskevic and S. A. Molcanov. Edited by E. B. Dynkin, with an introduction by A. N. Kolmogorov. Second edition, reprinted Izdat. ``Mir'', Moscow 1964 and 1967 (reprinted 1964 edition). 498 pp.
Feller, V.: Vvedenie v teoriyu veroyatnostej i ee prilozheniya. Tom 2. (Russian) [An introduction to probability theory and its applications. Vol. 2] Translated from the English by Ju. V. Prohorov Izdat. ``Mir'', Moscow, 1967. 752 pp.
Feller, V.: Vvedenie v teoriyu veroyatnostej i ee prilozheniya. Tom 1. (Russian) [An introduction to probability theory and its applications. Vol. 1] Translated from the third English edition and with a preface by Yu. V. Prokhorov. Second edition. With a preface by A. N. Kolmogorov. ``Mir'', Moscow, 1984. 528 pp.
Feller, V.: Vvedenie v teoriyu veroyatnostej i ee prilozheniya. Tom 2. (Russian) [An introduction to probability theory and its applications. Vol. 2] Translated from the second English edition and with a preface by Yu. V. Prokhorov. Second edition. ``Mir'', Moscow, 1984. 752 pp.
Yu. V. Prokhorov in his foreword to the first Russian edition of Volume II wrote the following:
It is surprising to read the following sentence of Yu.V. Prokhorov in his foreword to the Russian 1984 translation of the third English edition of Volume 1:
Spanish translations of both Feller's books have been published in Mexico.
Feller, William: Introducción a la teoría de probabilidades y sus aplicaciones, v. I (504 p.); [version española, Salvador Morales Vaca, Salvador, traductor], México : Limusa-Wiley, 1973
Feller, William: Introducción a la teoría de probabilidades y sus aplicaciones, v. II (738 p.) [version española, Sergio Fernandez Everest], México [etc.] : Limusa, 1985
Many thanks to Dr Radmila
Manfrino, Mexico, who kindly sent me
Feller, William: Wstep do rachunku prawdopodobienstwa. Tom I. (Polish) [Introduction to probability theory. Vol. I] Translated from the second English language edition. Third revised edition (!). Panstwowe Wydawnictwo Naukowe, Warsaw, 1977. 420 pp. First edition in 1966.
Feller, William: Wstep do rachunku prawdopodobienstwa. Tom II. (Polish) [Introduction to probability theory. Vol. II] Translated from the English. Second revised edition (!). Panstwowe Wydawnictwo Naukowe, Warsaw, 1978. 587 pp.
William Feller: Wstep do
rachunku prawdopodobienstwa (translated from the Third Edition),
Wydawnictwo: PWN, Maj
Znakomity podrecznik rachunku prawdopodobienstwa! Wznowienie poszukiwanego od lat klasycznego podrecznika, nalezacego do kanonu literatury dotyczacej ksztalcenia probabilistycznego. Zalety ksiazki to: - prosty i klarowny jezyk, zrozumialy dla absolwentów liceów ogólnoksztalcacych; - liczne zastosowania teorii prawdopodobienstwa w praktyce; - wiele przykladów i zadan; - zadania do samodzielnego rozwiazania z odpowiedziami. Publikacja przeznaczona jest dla studentów nauk scislych, przyrodniczych i ekonomicznych uniwersytetów, uczelni technicznych i akademii pedagogicznych.
In 2006 the first part of Feller's monograph had its 6th Polish edition, so the 2007 edition is already its seventh printing in Poland.
Feller, William K'ai-lü-lun chi ch'i yin-yung. Ts'e I. (Chinese) [Probability theory and its applications. Vol. I] Translated from the English by Hu Ti-ho and Lin Hsiang-ching Science Press, Peking 1964. xii+253 pp.
Many thanks to Professors Sibe and Pavao Mardesic for the above pages of Feller's book in Chinese, 1964, kept in the Library of the School of Mathematical Sciences in Beijing. The 1964 edition has been printed in 9,600 copies, and subsequent Chinese editions seem to exist:
The second volume of Feller's monograph has been issued in Chinese in 2007:
William Feller: An Introduction to Probability Theory and Its Applications, Volume 2, Chinese edition, 612 pp, ISBN 978-7-115-16735-4, source www.turingbook.com
William Feller: Bevezetés a valószínuségszámításba és alkalmazásaiba, Muszaki Kiadó, Budapest, 1978.
Many thanks to Professor Jozsef
Feller's books have been reedited by Wiley-Eastern, New Delhi, for the needs of mathematicians in India:
Feller's scientific interests in mathematics were very broad. He contributed to calculus, geometry, and functional analysis. About half of his papers are in the field of probability theory.
Especially important was his work in the period between 1950 and 1962, when "W. Feller broke new grounds on the theory of diffusion and Kolmogorov was delighted." See [Nitis Mukhopadhyay].
According to Mathematical Reviews, Feller's works are cited 1320 times by 1649 authors. The first part of his book is cited 390 times, and the second part 712 times. It should be noted that Math Reviews is reviewing math articles starting with the year 1939, so that Feller's very productive scientific work before that (that is, between 1926 and 1939) is not evidenced there. His most cited article (37 times) is
Besides two volumes of his famous book Feller wrote 104 scientific papers, see the complete list in the memorial issue of [Annals of Math. Statistics].
The list has been obtained using mathematical references from MathSciNet covering the period between 1970 (since Feller's death) and 2007, citing Feller's name.
Paul C. Kettler, Norway:
William Feller has the Erdös number equal to 1 (one): he has a joint paper with Paul Erdös written in 1949 (and with Pollard). Erdös wrote more than 1500 papers, and had 509 coauthors!
Feller-Tornier constant has been defined in Feller's paper written jointly with Erhard Tornier (1994-1982): "Mengentheoretische Untersuchungen von Eigenschaften der Zahlenreihe." Mathematische Annalen, Vol. 107, (1933) 188-232. The constant is defined as the density of natural numbers whose prime factorization contains an even number of distinct primes to powers larger than the first. It is equal to 0.661317... .
Tornier was 12 years older than Feller. In 1932 he became a Nazist, and ousted Feller from the University of Kiel in 1933 when he learned about his Jewish ancestry (for more information see [Thomas Hochkirchen], Abraham A. Fraenkel: Lebenskreise, Deutsche Verlag-Anstalt, Stuttgart, 1967, p. 155, and M. Pinl.: Kollegen in einer dunklen Zeit. III. Jber. Deutsch. Math.-Verein. 73 (1971/72), no. 1, 153-208). Feller had another joint paper with Tornier, published also in Mathematische Annalen, Vol 107, 1933 (Mass und Inhaltstheorie des Bairischen Nullraumes, pp. 165-187), and submitted in 1931.
W. Feller (in white suit) with P. Lévy (sitting) and M. Loeve on his right, and with B. de Finetti on his left, at the 2nd Berkeley Symposium, 1951; photo from Guiseppe Annichini: Bruno de Finetti - a great probabilist and a great man, EMS Newsletter, December 2006
In 1966 Feller had a great honour to become a member of the international scientific committee which had to elect candidates for the 1966 Fields Medal. The committee consisted of Georges de Rham (chair), Harold Davenport, Max Deuring, Willi Feller, Michael Al. Lavrentiev, Jean-Pierre Serre, Donald C. Spencer, and René Thom, see here. Recipients of the Fields Medal at the 1966 International Congress of Mathematicians in Moscow were Michael Francis Atiyah, Alexander Grothendieck, and Stephen Smale.
Feller is the author or coauthor of two more books:
According to the Mathematical Geneaology Project (with his name indicated as Willi K. Feller), William Feller was thesis advisor to 17 students in the period of 1941 to 1969, and he has as many as 609 descendants. Marta and Nikola Zdenkovic, Zagreb, informed me in 2006 that they do not know the meaning of initial "K." appearing in Feller's name in the Math Geneaology Project, and expressed their doubts about it. However, there exists a paper entitled Feller, W.K., "Statistical aspects of ESP", Journal of Parapsychology, 4 (1940), pp. 271-98. Here are the names of Feller's PhD students:
Feller's unofficial PhD student was Frank Spitzer, see here. His another unofficial PhD student seems to be Joanne Elliott. According to information that I obtained from two independent sources, the family of Feller's adopted Joanne Elliott when she was a grown up girl. She became a professional mathematician, and in one of her papers,
she wrote the following: "...This problem, suggested by W. Feller, arises in the theory of stochastic processess. ... The author wishes to thank William Feller for many helpful discussions..." Furthermore, Feller and Elliot published a joint paper:
William Feller mentions Joanne Elliott in the Introduction to Volume II of his monograph. In Joanne Elliott math geneaology we can find that the title of her dissertation was On Some Singular Integral Equations of the Cauchy Type, and advisor unknown (Feller?). She earned her PhD at Cornell in 1950, and recall that Feller was professor there in the period of 1945-1950. In Rutgers-New Brunswick Mathematics Graduate Faculty we found that she worked in potential theory, and that in 1974-77 she had a chair at Douglas College (at Rutgers since1964, Professor of Mathematics since 1965), retired since 1991.
Feller became a member of the Croatian Academy of Sciences and Arts in Zagreb (the then JAZU) in 1937, that is, at the age of 31. He was also a member of the Royal Danish Academy of Sciences, and the Royal Statistical Society in London. Shortly before his death he was elected as an honorary memebr of the London Mathematical Society. He was also a governor of the New Jersey section of the Mathematical Association of America (1958-1961, [PDF]), and a president of the Institute of Mathematical Statistics in 1947. According to [Roseblatt, p 12], Feller was a member of the American Philosophical Society.
William Feller was representative of several committees of the American Mathematical Society (AMS), see [PDF]:
Many outstading mathematicians from Princeton University were elected as members of the National Academy of Sciences: Solomon Lefschetz (1925), James W. Alexander (1930), John von Neumann (1937), Hermann Weyl (1940), Eugene P. Wigner (1945), Salomon Bochner (1950), Howard P. Robertson (1951), Norman E. Steenrod (1956), Emil Artin (1958), William Feller (1960), Donald C. Spencer (1961), John W. Milnor (1963), etc. See the complete list.
Feller was awarded the National Medal of Science of the USA in 1969 (Discipline: Mathematics and Computer Science). The National Medal of Science award was established by the U.S. Congress as a Presidential award. It was conferred in 1970 by president Richard Nixon to Feller's wife Clara during the official ceremony held in the White House, a month after Feller's death at the age of 63. This prestigeous medal has been conferred to him for
"In 1939 Feller and his wife moved to Providence, Rhode Island, where he became associate professor at Brown University, and the first Executive Editor of Mathematical Reviews which was founded in that year. Much credit is due to Feller for his pioneer work in establishing this journal, which is the formost mathematical review journal in the world."
The names of authors of this text, prepared in the first half of 1969, are not written, but according to other documents contained in the "Feller Nomination Package", kept at the NSF, it seems that the text was written by Joseph Doob, Mark Kac and Jerzy Neyman. All three of them were members of the National Academy of Sciences at that time, and Neyman received the Presidential Award in 1968, a year before Feller. Joseph Doob received the same award in 1979.
In the period of 1962-2013 there were altogether 481 recipients of the National Medal of Science (also called Presidential Award), and among them there were about 90 Nobel Prize wineers. In the field of Mathematics and Computer Science there were 59 of recipients, and Feller eighth in order:
Some mathematicians dedicated their scientific works to the memory of William Feller, for example by his PhD student H.P. McKean:
On July 17th 1953 William Feller delivered a lecture in the building of JAZU, Zagreb, in Croatian language, under the title "Matematicka teorija difuzije" (Mathematical theory of diffusion), see [Mardesic, Some data...].
He was in touch with his relatives in Zagreb, as well as with his colleagues at the University of Zagreb. During the post WWII period Feller visited Zagreb on four occasions: in 1953, 1956, 1957 and 1958 (a letter from 1957, written in Croatian by the mother of Marta and Nikola Zdenkovic, mentions that "uncle Will and Clara" are in Zagreb, and that they have brought toys for Marta and Nikola from the USA).
He helped professor Sibe Mardesic from Zagreb, at that time a young scientist, to spend the academic years 1957/58 and 1958/59 at the Institute for Advanced Study in Princeton, see [here]. S. Mardesic was introduced to Feller in person by Zeljko Markovic in his office, when Feller visited Department of Mathematics and had a lecture there, PMF, Zagreb, in 1956. According to [Vranic, p. 352], "...not only that Vilim Feller did not hide his Croatian descent, but he was also proud of it."
J. Dieudonné, a well known French mathematician, and a member of the Bourbaki group, in his book A panorama of pure mathematics - As seen by N. Bourbaki (Academic Press, New York, London, 1982), indicated that the main ideas of probability theory are related to the names of:
Many thanks to Mr Paul C. Kettler, Norway, a former student of professor Feller, for this wonderful information (2006). Here is another lovely detail from Feller's lectures, described by Mr Kettler:
[This is why some people call number 17 - the Feller number, see Wikipedia; D.Z.] One other anecdote by Mr. Kettler:
A lovely example of a computation á la Feller is provided by his student Gian Carlo Rota, a well known Italian-American mathematician. One of the first examples of definite integrals computed at the calculus level is integration of the the function sin2x from zero to 2pi. Here is how Feller does it. First integrate the identity sin2x + cos2x = 1 from zero to 2pi, and then note (by a trivial geometric arguement) that both integrals on the left-hand side are equal. Hence, the required integral is equal to pi.
Besides his native Croatian, William Feller spoke also German, English, French, Latin, Hebrew, and very probably Swedish as well (recall that he spent five years in Sweden, from 1934 till 1939). And concerning Feller's fluency in Swedish, here is a testimony of Ulf Grenander, a Swedish mathematician: "... later I had many contacts with him. He used to write to me in Swedish!" According to the information that I obtained from Mr. Nikola Zdenkovic in 2006, his hobby was translating old texts from Sanskrit.
Professor Feller was a member of editorial boards of two prestigeous journals: Transactions of the American Mathematical Society and the Annals of Mathematical Statistics.
Feller's PhD student Benjamin Weiss has nice memories about his professor:
Ulf Grenander in his interview for Statistical Science described Feller's character as follows:
From an introductory article written by the editorial board of [Annals of Math. Statistics] on the occasion of death of William Feller in 1970, we cite the following:
In the same issue of the [Annals of Math. Statistics] we can find the following dedication on the separate page:
Feller: Are life scientsts overawed by
Scientific Research, February 3, 1969, pp 24-29
In the same obituary Joseph Doob wrote the following:
Joe Doob said the following in his conversation with J.L. Snell:
Richard Feynman, a famous american physicist and Nobel prize winner, wrote in his bestseller "Surely You're Joking Mr. Feynman"!, p. 210, that he liked to talk to Professor Feller at Cornell. Feller worked there from 1945 till 1950, as well as Feynman.
S Ramasubramanian (Bangalore, India, PDF):
Let us see a part of autobiographical sketch of a winner of the 1998 Steel Prize awarded by the American Mathematical Society, which only mathematicians can write:
See also Zeilberger's article: Fully AUTOMATED Computerized Redux of Feller's (v.1) Ch. III (and Much More!), accompanied by Maple package FELLER.
Professor Donald A. Dawson (Ph.D., MIT, 1963) described his scientific geneaology in a similar way:
We learned from Personajes de la Astronomía y la Astronáutica, Venezuela, that there is an asteroid bearing the name of William Feller (1906-1970):
For a detiled description of the Feller planetoid 21276 Feller (1996 TF5), discovered in 1996, see NASA. There we can see Feller's mini-biography (an anonimous author forgot to mention that Feller taught at Princeton as well):
Here is a list of books on Probability Theory in which Feller's results are mentioned either in chapter or section titles, or in some other way. Many thanks to Professor Sibe Mardesic for this list which he collected (with help of Dr. Hrvoje Sikic and Dr. Zoran Vondracek, University of Zagreb) for the needs of the exhibition Centuries of Natural Sciences in Croatia, 1996, Zagreb:
Kiyosi Ito and Henry P. McKean, Jr.: Diffusion Processes and Their Sample Paths, Academic Press, Springer Verlag, 1965
... W. Feller has our best thanks, his ideas run through the whole book, and we shall think it a success if it pleases him. (p. XIII)
5.7. Feller's Brownian
Kai Lai Chung: Lectures from Markov Processes to Brownian Motion, Springer Verlag, 1982
2.2. Feller Process
4 The Lindeberg-Feller Theorem
III. 2. Feller Processes
Paul-André Meyer: Processus de Markov, Springer Verlag, 1967
Panorama of Pure Mathematics As Seen by N. Bourbaki,
7. The Originators
Stewart N. Ethier and Tomas G. Kurtz: Markov processes, Characterization and Convergence, John Wiley & Sons, 1986
2. Markov Jump Processes and Feller Processes
4. Fellerovskie perehodnye funkcii v kompaktah
L.C.V. Rogers and David Williams: Diffusions, Markov Processes, and Martingales, Volume 1, Cambridge University Press, 1979
Feller-Dynkin (FD) Semigroups, pp. 240-262
The Feller-McKean chain, III-23, III.35
L.C.V. Rogers and David Williams: Diffusions, Markov Processes, and Martingales, Volume 2: Ito Calculus, John Wiley & Sons, 1978
57. Feller Brownian motions
Ioannis Karatzas and Steven E. Shreve: Brownian motion and Stochastic Calculus, Springer Verlag, 1991
5.29 Theorem (Feller's (1952) Test for Explosions)
Kosaku Yosida: Functional Analysis, Grundlehren der mathematischen Wissenschaften 123, Springer-Verlag, 1980 (6th ed.)
XIII. The generalized Laplacian of W. Feller, pp 403-408
The ambitious and voluminous Encyclopedia of Mathematics issued in the former USSR in five books (Matematicheskaya enciklpediya 1-5, Moscow, 1977-1985), has an extensive article entitled Feller process (Fellerovskij process, Volume 5), written by S.N. Smirnov. The author states that Feller processes (introduced in 1952) represent probabilistic generalizations of topological dynamics. The article mentions some other articles and books related to Feller processes, for example, Dynkin and
I.V. Girsanov: Teorija verojatnostej i ee primenenija, 1960, t. 5, No 3, pp. 314-330.
S. H. Lehnigk: The Generalized Feller Equation and Related Topics, Pitman Monographs and Surveys in Pure and Applied Mathematics, Volume 68, Longman, 1993 (304 pp)
Michael Demuth, J.A. Van Casteren: Stochastic Spectral Theory for Selfadjoint Feller Operators: A Functional Integration Approach, Birkhäuser Verlag, 2000
Jan A. van Casteren:
Markov Processes, Feller
Semigroups and Evolution Equations
Radu Zaharopol: Invariant Probabilities of Markov-Feller Operators and Their Support, Birkhäuser Verlag, 2005
photo from www.abeys.com.au
Kai Lai Chung: Chance and Choice: Memorabilia, World Scientific Publishing, 2004, contains Chung's old photo with Feller
Krishna B. Athreya, Soumendra N. Lahiri: Measure Theory and Probability Theory, Springer, 2006
11.1 Lindeberg-Feller theorems
184.108.40.206 Feller continuity
Kiyosi Itô: Essentials of Stochastic Processes, translated from the Japanese 1957 edition by Yuji Ito, published by American Mathematical Society, 2006
5.5. Feller's Canonical Scale 132
5.6. Feller's Canonical Measure 136
5.7. Feller's Canonical Form 137
5.11. Classification of Boundary Points with respect to Feller's Operator 149
Niels Jacob: Pseudo-Differential Operators and Markov Processes, London: Imperial College Press
Volume 1: Fourier Analysis and Semigroups, 2001
Generators of Feller Semigroups
Volume 2: Generators and Their Potential Theory, 2002
Generators of Feller and Sub-Markovian Semigroups: Second Order Elliptic Differential Operators
Constructing Feller and Sub-Markovian Semigroups
Volume 3: Markov Processes and Applications, 2005
Stochastic Integration with Jumps (Encyclopedia of Mathematics and Its Applications) - US - ISBN:9780521811293 Bichteler, Klaus / Publisher: Cambridge Univ Press, 2002/05
Feller Semigroup and Generator
Stochastic Representation of Feller Semigroups
The Natural Extension of a Feller Semigroup
In July 2005 Vamsikrishna
Kalapala, (B. Tech., Indian Institute of Technology, Chennai, 1998,
India) defended his Master Thesis in Computer Science, entitled A
Compilation of Results on Phase Transitions, Scale-Invariance
at The University of New Mexico (Albuqureque), USA. On page 2 we can
read the following dedication, referring to volume 1 of Feller's Introduction
to Probability Theory and Its Applications:
As we see, the dedication was written 35 years after Feller's death!
Charles M. Grinstead (Swarthmore College) and J. Laurie Snell (Dartmouth College), in their book Introduction to Probability (available online!) published by the AMS (American Mathematical Society), provide the following acknowledgments:
From Tony Smith's Bounded Complex Domains:
A quotation confirming the above discussion is the following (web site by Donald Wilson Zimmerman):
Only yesterday the practical things of today were decried as impractical, and the theories which will be practical tomorrow will always be branded as valueless by the practical men of today.
Another example is 1937 Feller's review for Zentralblatt of lecture notes of Jerzy Neyman, when Feller was at the age of 31, living in Sweden:
For the Bulletin of the AMS J. Wolfowitz wrote in 1950 the following about Feller's 1950 monograph, part I:
The Zagreb cemetery Mirogoj is one of the most beautiful in Europe. In order to reach the Feller family tomb, at the main entrance one has to turn to the left and proceed for about 100 meters. The Feller family tomb is considered to be one of the most beautiful pieces of art that can be seen in Arcades of the Zagreb cemetery.
The name of Vilim Feller is mentioned in a memorial tablet, among those descendants of the Feller family which were burried outside of their homeland. The name of his wife Clara Nielsen Feller is also here.
Here is the front view to the family tomb of Feller's:
Feller's mother Ida and father Eugen Viktor Feller
are burried here,
With kind permission of prof. Marta Zdenkovic, Zagreb
Ida and Eugen Viktor Feller, Vilim's parents
On the following photo you can see part of arcades of the Zagreb cemetery where the Feller family tomb is situated:
My deep gratitude goes to Marta and Nikola Zdenkovic, Zagreb, for permission to use the photos from their family collection, and for many details about the family history. They are both grandchildren of William Feller's oldest brother Ferdinand. Many thanks to Dr. J.R. Goldman, USA, one of 17 PhD students of professor Feller, for sending me his very nice photos. Dr. Ulrich Hunger from the Universitätsarchiv Göttingen generously helped me with valuable information about Feller's doctorate. Many thanks to Paul C. Kettler, Norway, a student of professor Feller, for his kind help. I am deeply indepted to academician Sibe Mardesic, outstanding Croatian topologist, for generous help with archival and other material, and for his personal recollections about Vilim Feller, and also to his son professor Pavao Mardesic for copies of the 1964 Chinese edition of Feller's book. Professor Jozsef Pelikan from Budapest kindly sent photos of the Hungarian edition of Feller's book. Many thanks to Dr. Radmila Bulajic Manfrino, Mexico, for copies of the Spanish edition, and to Wasilio Koslow, MSc, Venezuela, for color photos. Professor John J. O'Connor from North Haugh, University of St Andrews, Scotland, kindly sent me a copy of Feller's plenary lecture in PDF (6.8 MB) form.
My dear friend Julija Vojkovic, Zagreb, helped me with her professional scanning skills. Also, my dear friend Dr. Zeljko Hanjs helped me with finding two mathematical scientific works of Feller written in Croatian, see here. Mr. Tvrtko Tadic, a student of mathematics at the University of Zagreb, helped me with information about Feller's secondary schooling in Zagreb. I express my gratitude to Marta Kolar and Ines Leskovar, students at the Factulty of Electrical Engineering and Computing of the University of Zagreb, for their effort to translate the text into Croatian. Many thanks to Sinisa Milicic, University of Zagreb, for information about personal contacts between Feller and Feynman.
Errata. It has been stated by Gian Carlo Rota, MIT (Indiscrete Thaughts, Birkhäuser, 1996) that "Feller's father's surname was a "Slavic tongue twister", which William changed at the age of twenty". This is wrong, that is, the orginal second name of William Feller was always Feller, as well as for his father and grandfather. Many thanks to Marta Zdenkovic for clarifying this matter. We have noticed this mistake being spread throughout the web on numerous pages dealing with Feller. Rota's claim that the original name of William Feller was Willibrord is also wrong, the original name was Vilibald Srecko (Willibald Felix in English).
Nitis Mukhopadhyay: Probability and Statistical Inference (Statistics, a Series of Textbooks and Monographs), in the Appendix on p. 599 it is stated that "William Feller was born on July 7, 1906, in Zagreb, Yugoslavia (now Croatia). After finishing Masters degree there in 1925, ...". It should be noted that Feller was not born in Yugoslavia, since it did not exist in 1906 (the ex-Yugoslavia was named so in 1929, and its predecessor had existed since 1918). In time of Feller's birth Croatia was a part of Austria-Hungary, with its own Parliament in Zagreb. For more details see here. The same mistake can be found in [Roseblatt, p 3].
We have stated at the beginning of this article that William Feller was Croatian - American mathematician. However, it would probably be more appropriate to call him Croatian - German - Danish - Swedish - American (...) mathematician. Similar is the case with many other scientists.
Request. I would deeply appreciate any additional reliable information related to the life and work of William Feller, including photos, especially if You had luck to have been his student or friend (e-mail: darko.zubrinicYYATYYgmail.com; please, remove Y's, don't ask me why).
Feller's papers published in
Razgovor o Vilimu Felleru na poziv gđe. Karoline Vidović Krišto za emisiju Lica Hrvatske na HTV-u studenoga 2012. Od šeste do dvadesete minute (6-20 min.).
Lipnja 2011. godine je g. Saša Šimpraga predložio da jedna zagrebačka ulica bude nazvana imenom Vilima Fellera. Svibnja 2012. je Odbor za imenovanje naselja, ulica i trgova u Zagrebu donio je odluku da će jedna od zagrebačkih ulica nositi ime Vilima Fellera:
Ulica koja se odvaja iz Ulice Stjepana Gradića (istočno od kućnog broja 13) u smjeru zapada, prolazi križanje s Ulicom Nikole Andrića i završava kao slijepa ulica, imenuje se u spomen na matematičara na Vilima Fellera i dobiva ime Ulica Vilima Fellera.
Feller's blog: http://feller.zpm.fer.hr/
D.Ž.: William Feller [PDF], 5th Croatian Mathematical Congress, Rijeka 2012