Salomon Bochner (20 August 1899 – 2 May 1982) was an Austrian
mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems.
Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...
, known for work in
mathematical analysis
Analysis is the branch of mathematics dealing with continuous functions, limit (mathematics), limits, and related theories, such as Derivative, differentiation, Integral, integration, measure (mathematics), measure, infinite sequences, series (m ...
,
probability theory
Probability theory is the branch of mathematics concerned with probability. Although there are several different probability interpretations, probability theory treats the concept in a rigorous mathematical manner by expressing it through a set o ...
and
differential geometry.
Life
He was born into a Jewish family in
Podgórze (near
Kraków
Kraków (), or Cracow, is the second-largest and one of the oldest cities in Poland. Situated on the Vistula River in Lesser Poland Voivodeship, the city dates back to the seventh century. Kraków was the official capital of Poland until 159 ...
), then Austria-Hungary, now
Poland
Poland, officially the Republic of Poland, , is a country in Central Europe. Poland is divided into Voivodeships of Poland, sixteen voivodeships and is the fifth most populous member state of the European Union (EU), with over 38 mill ...
. Fearful of a Russian invasion in
Galicia
Galicia may refer to:
Geographic regions
* Galicia (Spain), a region and autonomous community of northwestern Spain
** Gallaecia, a Roman province
** The post-Roman Kingdom of the Suebi, also called the Kingdom of Gallaecia
** The medieval King ...
at the beginning of
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, ...
in 1914, his family moved to Germany, seeking greater security. Bochner was educated at a
Berlin
Berlin is Capital of Germany, the capital and largest city of Germany, both by area and List of cities in Germany by population, by population. Its more than 3.85 million inhabitants make it the European Union's List of cities in the European U ...
gymnasium (secondary school), and then at the
University of Berlin
The Humboldt University of Berlin (german: link=no, Humboldt-Universität zu Berlin, abbreviated HU Berlin) is a public research university in the central borough of Mitte in Berlin, Germany.
The university was established by Frederick Will ...
. There, he was a student of
Erhard Schmidt
Erhard Schmidt (13 January 1876 – 6 December 1959) was a Baltic German mathematician whose work significantly influenced the direction of mathematics in the twentieth century. Schmidt was born in Tartu (german: link=no, Dorpat), in the Gover ...
,
writing a dissertation involving what would later be called the
Bergman kernel. Shortly after this, he left the academy to help his family during the
escalating inflation. After returning to mathematical research, he lectured at the
University of Munich
The Ludwig Maximilian University of Munich (simply University of Munich or LMU; german: link=no, Ludwig-Maximilians-Universität München) is a public research university in Munich, Bavaria, Germany. Originally established as the University of ...
from 1924 to 1933. His academic career in Germany ended after the
Nazis came to power in 1933, and he left for a position at
Princeton University
Princeton University is a private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth as the College of New Jersey, Princeton is the fourth-oldest institution of higher education in the United States and one of the n ...
. He was a visiting scholar at the
Institute for Advanced Study
The Institute for Advanced Study (IAS), located in Princeton, New Jersey, in the United States, is an independent center for theoretical research and intellectual inquiry. It has served as the academic home of internationally preeminent scholar ...
in 1945-48. He was appointed as Henry Burchard Fine Professor in 1959, retiring in 1968. Although he was seventy years old when he retired from Princeton, Bochner was appointed as Edgar Odell Lovett Professor of Mathematics at
Rice University
William Marsh Rice University (Rice University) is a private research university in Houston, Texas. It is on a 300-acre campus near the Houston Museum District and adjacent to the Texas Medical Center. Rice is ranked among the top universit ...
and went on to hold this chair until his death in 1982. He became Head of Department at Rice in 1969 and held this position until 1976. He died in
Houston, Texas. He was an
Orthodox Jew.
Mathematical work
In 1925 he started work in the area of
almost periodic functions, simplifying the approach of
Harald Bohr by use of
compactness
In mathematics, specifically general topology, compactness is a property that seeks to generalize the notion of a closed and bounded subset of Euclidean space by making precise the idea of a space having no "punctures" or "missing endpoints", i ...
and
approximate identity arguments. In 1933 he defined the
Bochner integral, as it is now called, for vector-valued functions.
Bochner's theorem on
Fourier transform
A Fourier transform (FT) is a mathematical transform that decomposes functions into frequency components, which are represented by the output of the transform as a function of frequency. Most commonly functions of time or space are transformed, ...
s appeared in a 1932 book. His techniques came into their own as
Pontryagin duality
In mathematics, Pontryagin duality is a duality between locally compact abelian groups that allows generalizing Fourier transform to all such groups, which include the circle group (the multiplicative group of complex numbers of modulus one), ...
and then the representation theory of
locally compact groups developed in the following years.
Subsequently, he worked on
multiple Fourier series, posing the question of the
Bochner–Riesz mean The Bochner–Riesz mean is a summability method often used in harmonic analysis when considering convergence of Fourier series and Fourier integrals. It was introduced by Salomon Bochner as a modification of the Riesz mean.
Definition
Define
:(\x ...
s. This led to results on how the Fourier transform on
Euclidean space
Euclidean space is the fundamental space of geometry, intended to represent physical space. Originally, that is, in Euclid's ''Elements'', it was the three-dimensional space of Euclidean geometry, but in modern mathematics there are Euclidean sp ...
behaves under rotations.
In differential geometry,
Bochner's formula on
curvature
In mathematics, curvature is any of several strongly related concepts in geometry. Intuitively, the curvature is the amount by which a curve deviates from being a straight line, or a surface deviates from being a plane.
For curves, the can ...
from 1946 was published. Joint work with
Kentaro Yano (1912–1993) led to the 1953 book ''Curvature and Betti Numbers''. It had consequences, for the
Kodaira vanishing theory,
representation theory, and
spin manifolds. Bochner also worked on
several complex variables (the
Bochner–Martinelli formula In mathematics, the Bochner–Martinelli formula is a generalization of the Cauchy integral formula to functions of several complex variables, introduced by and .
History
Bochner–Martinelli kernel
For , in \C^n the Bochner–Martinelli ke ...
and the book ''Several Complex Variables'' from 1948 with
W. T. Martin).
Selected publications
*
**
**
*
*
*
2016 reprint*
*
2013 reprint*
2014 reprint*
*
*
*
*
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See also
*
Bochner almost periodic functions
*
Bochner–Kodaira–Nakano identity
In mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in mod ...
*
Bochner Laplacian
*
Bochner measurable function
References
External links
*
*
National Academy of Sciences Biographical Memoir*
{{DEFAULTSORT:Bochner, Salomon
1899 births
1982 deaths
20th-century German mathematicians
20th-century American mathematicians
Jewish scientists
Differential geometers
Complex analysts
Mathematical analysts
Measure theorists
PDE theorists
Princeton University faculty
Rice University faculty
Polish Orthodox Jews
American Orthodox Jews
Jews from Galicia (Eastern Europe)
Scientists from Berlin
Institute for Advanced Study visiting scholars
Jewish emigrants from Nazi Germany to the United States