Giovanni Battista Rizza (7 February 1924 – 15 October 2018), officially known as Giambattista Rizza, was an Italian mathematician, working in the fields of
complex analysis of several variables and in
differential geometry: he is known for his contribution to
hypercomplex analysis In mathematics, hypercomplex analysis is the basic extension of real analysis and complex analysis to the study of functions where the argument is a hypercomplex number. The first instance is functions of a quaternion variable, where the argume ...
, notably for extending
Cauchy's integral theorem
In mathematics, the Cauchy integral theorem (also known as the Cauchy–Goursat theorem) in complex analysis, named after Augustin-Louis Cauchy (and Édouard Goursat), is an important statement about line integrals for holomorphic functions in t ...
and
Cauchy's integral formula
In mathematics, Cauchy's integral formula, named after Augustin-Louis Cauchy, is a central statement in complex analysis. It expresses the fact that a holomorphic function defined on a disk is completely determined by its values on the boundary ...
to complex functions of a
hypercomplex variable,
[According to the motivation for the award of the "'' Premio Ottorino Pomini''", reported on the , "Sono particolarmente degni di nota i risultati sui teoremi integrali per le funzioni regolari, sulle estensioni della formula integrale di Cauchy alle funzioni monogene sulle algebre complesse dotate di modulo commutative e sul conseguente sviluppo della relativa teoria, ed infine sulla struttura delle algebre di Clifford" ("Particularly notable results are the ones on the integral theorems for regular functions, the ones on the extension of Cauchy integral formula to complex commutative algebras with modulus, and lastly the ones on the structure of ]Clifford algebras
In mathematics, a Clifford algebra is an algebra generated by a vector space with a quadratic form, and is a unital associative algebra. As -algebras, they generalize the real numbers, complex numbers, quaternions and several other hyper ...
"). the theory of
pluriharmonic function In mathematics, precisely in the theory of functions of several complex variables, a pluriharmonic function is a real valued function which is locally the real part of a holomorphic function of several complex variables. Sometimes such a functi ...
s and for the introduction of the now called
Rizza manifolds.
Biography
Life and academic career
Born in
Piazza Armerina
Piazza Armerina ( Gallo-Italic of Sicily: ''Ciazza''; Sicilian: ''Chiazza'') is a ''comune'' in the province of Enna of the autonomous island region of Sicily, southern Italy.
History
The city of Piazza (as it was called before 1862) developed ...
, the son of Giovanni and Angioletta Bocciarelli, he graduated from the
Università degli Studi di Genova
The University of Genoa, known also with the acronym UniGe ( it, Università di Genova), is one of the largest universities in Italy. It is located in the city of Genoa and regional Metropolitan City of Genoa, on the Italian Riviera in the Liguri ...
, earning his
laurea
In Italy, the ''laurea'' is the main post-secondary academic degree. The name originally referred literally to the laurel wreath, since ancient times a sign of honor and now worn by Italian students right after their official graduation ceremony ...
degree in 1949 under the direction of
Enzo Martinelli.
[According to , he was his first doctoral student.] In 1956 he was in
Rome
, established_title = Founded
, established_date = 753 BC
, founder = King Romulus (legendary)
, image_map = Map of comune of Rome (metropolitan city of Capital Rome, region Lazio, Italy).svg
, map_caption ...
at the
INdAM, having been awarded a scholarship for his early research activities. A year later, in 1957, he was elected "''discepolo ricercatore''" in the same institute.
[See .] During the same year, he gave some lectures on topics belonging to the field of
several complex variables, later included in the lecture notes . In Rome he also met
Lucilla Bassotti, who eventually become his wife. In 1961, he won the competitive examination for the chair of "Geometria analitica con elementi di Geometria Proiettiva e Geometria Descrittiva con Disegno" of the
University of Parma
The University of Parma ( it, Università degli Studi di Parma, UNIPR) is a public university in Parma, Emilia-Romagna, Italy. It is organised in nine departments. As of 2016 the University of Parma has about 26,000 students.
History
During the ...
, scoring first out of the three finalists: a year later, in 1962, he became
extraordinary professor
Academic ranks in Germany are the titles, relative importance and power of professors, researchers, and administrative personnel held in academia.
Overview
Appointment grades
* (Pay grade: ''W3'' or ''W2'')
* (''W3'')
* (''W2'')
* (''W2'', ...
, and then, in 1965,
ordinary professor
Academic ranks in Germany are the titles, relative importance and power of professors, researchers, and administrative personnel held in academia.
Overview
Appointment grades
* (Pay grade: ''W3'' or ''W2'')
* (''W3'')
* (''W2'')
* (''W2'', ...
to the same chair. In 1979 he became ordinary professor of "''Geometria superiore''", holding that chair uninterruptedly until 1994: from 1994 up to his retirement in 1997, he was "''professore fuori ruolo''" in the same department of mathematics where he worked for more than 35 years.
Apart from his research and teaching work, he was actively involved as a member of the editorial board of the "''
Rivista di Matematica della Università di Parma''", and served also as the journal director from 1992 to 1997.
Rizza died in Parma on 15 October 2018, at the age of 94.
Honors
In 1954 he was awarded the
Ottorino Pomini prize by the
Unione Matematica Italiana
The Italian Mathematical Union ( it, Unione Matematica Italiana) is a mathematical society based in Italy.
It was founded on December 7, 1922 by Luigi Bianchi, Vito Volterra, and most notably, Salvatore Pincherle, who became the Union's first P ...
, jointly with
Gabriele Darbo: the judging commission was composed by
Giovanni Sansone (as the president),
Alessandro Terracini,
Beniamino Segre
Beniamino Segre (16 February 1903 – 2 October 1977) was an Italian mathematician who is remembered today as a major contributor to algebraic geometry and one of the founders of finite geometry.
Life and career
He was born and studied in Turin ...
,
Giuseppe Scorza-Dragoni,
Carlo Miranda
Carlo Miranda (15 August 1912 – 28 May 1982) was an Italian mathematician, working on mathematical analysis, theory of elliptic partial differential equations and complex analysis: he is known for giving the first proof of the Poincaré–Mir ...
,
Mario Villa and
Enzo Martinelli (as the secretary).
In 1973 he was awarded the
golden medal "
Benemeriti della Scuola, della Cultura, dell'Arte" by the
President of the Italian Republic
President most commonly refers to:
* President (corporate title)
*President (education), a leader of a college or university
* President (government title)
President may also refer to:
Automobiles
* Nissan President, a 1966–2010 Japanese ...
,
as an acknowledgement his research and teaching and achievements as civil servant at the University of Parma.
In 1995, to celebrate his 70th birthday, an international conference on differential geometry was organized in Parma: the
proceedings
In academia and librarianship, conference proceedings is a collection of academic papers published in the context of an academic conference or workshop. Conference proceedings typically contain the contributions made by researchers at the confere ...
were later published as a special issue of the "Rivista di Matematica della Università di Parma".
In 1999 the University of Parma, where he worked for more than 35 years, awarded him the title of
professor emeritus
''Emeritus'' (; female: ''emerita'') is an adjective used to designate a retired chair, professor, pastor, bishop, pope, director, president, prime minister, rabbi, emperor, or other person who has been "permitted to retain as an honorary title ...
.
Rizza was an honorary member of the
Balkan Society of Geometers and life member of the
Tensor Society.
Personality traits
Enzo Martinelli described Giovanni Battista Rizza as a passionate researcher with a "strong intellectual force",
[ precisely characterizes Rizza's scientific work as developed with "''...molta passione e forza intellettuale...''", i.e. with (English translation) "...much passion and intellectual force...".] and his scientific work as rich of
geometrical
Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is ...
ideas, denoting his strong
algorithm
In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific problems or to perform a computation. Algorithms are used as specifications for performing ...
ic ability. According to Martinelli, Rizza is also a skilled organizer:
[See .] his ability in organizational tasks is also acknowledged and praised by , who also alludes the positive opinions of colleagues and students alike about his involvement in research, teaching and administrative duties at the mathematics department of the
University of Parma
The University of Parma ( it, Università degli Studi di Parma, UNIPR) is a public university in Parma, Emilia-Romagna, Italy. It is organised in nine departments. As of 2016 the University of Parma has about 26,000 students.
History
During the ...
.
Work
Research activity
Giovanni Battista Rizza authored 53 research papers and 30 other scientific works, including research announcements, short notes, surveys and reports: he also wrote didactic notes and papers on historical topics, including commemorations of other scientists. His main fields of research were the
theory of functions on algebras, the
theory of functions of several complex variables, and
differential geometry.
Theory of functions on algebras
The theory of functions on algebras, also referred to as
hypercomplex analysis In mathematics, hypercomplex analysis is the basic extension of real analysis and complex analysis to the study of functions where the argument is a hypercomplex number. The first instance is functions of a quaternion variable, where the argume ...
, is the study of
function
Function or functionality may refer to:
Computing
* Function key, a type of key on computer keyboards
* Function model, a structured representation of processes in a system
* Function object or functor or functionoid, a concept of object-oriente ...
s whose
domain
Domain may refer to:
Mathematics
*Domain of a function, the set of input values for which the (total) function is defined
**Domain of definition of a partial function
**Natural domain of a partial function
**Domain of holomorphy of a function
* Do ...
is a
subset of an
algebra
Algebra () is one of the broad areas of mathematics. Roughly speaking, algebra is the study of mathematical symbols and the rules for manipulating these symbols in formulas; it is a unifying thread of almost all of mathematics.
Elementary ...
. The first works of Giovanni Battista Rizza belong to this field of research, and he was awarded the
Premio Ottorino Pomini for his contributions.
His first main result is the extension of
Cauchy's integral theorem
In mathematics, the Cauchy integral theorem (also known as the Cauchy–Goursat theorem) in complex analysis, named after Augustin-Louis Cauchy (and Édouard Goursat), is an important statement about line integrals for holomorphic functions in t ...
to every
monogenic function A monogenic function is a complex function with a single finite derivative.
More precisely, a function f(z) defined on A \subseteq \mathbb is called monogenic at \zeta \in A , if f'(\zeta) exists and is finite, with:
f'(\zeta) = \lim_\frac
...
on a general
complex algebra ,
:
where is a
1-dimensional cycle homologous to zero, and also satisfying other technical conditions.
Few years later, he extended
Cauchy's integral formula
In mathematics, Cauchy's integral formula, named after Augustin-Louis Cauchy, is a central statement in complex analysis. It expresses the fact that a holomorphic function defined on a disk is completely determined by its values on the boundary ...
to every
monogenic function A monogenic function is a complex function with a single finite derivative.
More precisely, a function f(z) defined on A \subseteq \mathbb is called monogenic at \zeta \in A , if f'(\zeta) exists and is finite, with:
f'(\zeta) = \lim_\frac
...
on a
commutative
In mathematics, a binary operation is commutative if changing the order of the operands does not change the result. It is a fundamental property of many binary operations, and many mathematical proofs depend on it. Most familiar as the name of ...
normed real algebra ,
isomorphic to a given complex algebra : precisely, he proves the formula
:
where
* identifies indifferently a
point
Point or points may refer to:
Places
* Point, Lewis, a peninsula in the Outer Hebrides, Scotland
* Point, Texas, a city in Rains County, Texas, United States
* Point, the NE tip and a ferry terminal of Lismore, Inner Hebrides, Scotland
* Point ...
in the complex algebra or in its isomorphic real algebra ,
* is again a
1-dimensional cycle homologous to zero, and satisfying other technical conditions,
* is the
winding number
In mathematics, the winding number or winding index of a closed curve in the plane around a given point is an integer representing the total number of times that curve travels counterclockwise around the point, i.e., the curve's number of t ...
of the cycle respect to the
zero divisor
In abstract algebra, an element of a ring is called a left zero divisor if there exists a nonzero in such that , or equivalently if the map from to that sends to is not injective. Similarly, an element of a ring is called a right zer ...
locus
Locus (plural loci) is Latin for "place". It may refer to:
Entertainment
* Locus (comics), a Marvel Comics mutant villainess, a member of the Mutant Liberation Front
* ''Locus'' (magazine), science fiction and fantasy magazine
** ''Locus Award' ...
for the considered algebra.
Theory of analytic functions of several complex variables
Rizza published only three work in this field: in the first one, the highly remarkable memoir , he extends to pluriharmonic functions of
real variables, , the methods introduced by Enzo Martinelli in order to give new proof of a result of
Luigi Amoroso
Luigi Amoroso (26 March 1886 – 28 October 1965) was an Italian neoclassical economist influenced by Vilfredo Pareto. He provided support for and influenced the economic policy during the fascist regime.
Work
The microeconomical concept of the ...
for pluriharmonic functions of four real variables. Precisely, he proves the following formula
where
* is a polyharmonic function defined on a
bounded domain
Domain may refer to:
Mathematics
*Domain of a function, the set of input values for which the (total) function is defined
**Domain of definition of a partial function
**Natural domain of a partial function
**Domain of holomorphy of a function
* Do ...
,
* is a
real
Real may refer to:
Currencies
* Brazilian real (R$)
* Central American Republic real
* Mexican real
* Portuguese real
* Spanish real
* Spanish colonial real
Music Albums
* ''Real'' (L'Arc-en-Ciel album) (2000)
* ''Real'' (Bright album) (2010) ...
analytic function
In mathematics, an analytic function is a function that is locally given by a convergent power series. There exist both real analytic functions and complex analytic functions. Functions of each type are infinitely differentiable, but complex ...
defining the
boundary
Boundary or Boundaries may refer to:
* Border, in political geography
Entertainment
* ''Boundaries'' (2016 film), a 2016 Canadian film
* ''Boundaries'' (2018 film), a 2018 American-Canadian road trip film
*Boundary (cricket), the edge of the pla ...
of by the equation
:
* is a linear combination of the
Levi forms of relative to couples of
complex variable
Complex analysis, traditionally known as the theory of functions of a complex variable, is the branch of mathematical analysis that investigates functions of complex numbers. It is helpful in many branches of mathematics, including algebrai ...
s,
* is a linear
tangential operator defined on .
Formula express a condition the
normal derivative
In mathematics, the directional derivative of a multivariable differentiable (scalar) function along a given vector v at a given point x intuitively represents the instantaneous rate of change of the function, moving through x with a velocity ...
of the boundary value of a pluriharmonic function on domain with real analytic boundary must satisfy. It can be used to construct an integral representation for pluriharmonic functions on such kind of domains, by using the
Green's formula for the
Laplacian, and also to establish an
integro-differential equation
In mathematics, an integro-differential equation is an equation that involves both integrals and derivatives of a function.
General first order linear equations
The general first-order, linear (only with respect to the term involving derivati ...
boundary values of pluriharmonic functions must satisfy. Rizza's result motivated other works on the same topic by Gaetano Fichera, Paolo de Bartolomeis and
Giuseppe Tomassini.
[See the hystorical survey sections in and the work .]
Selected publications
Research works
*. In this work Rizza extends the classical Cauchy's integral theorem to monogenic functions on a general complex algebra.
*.
*.
*.
*. A short research announcement describing briefly the results proved in .
*, available a
DigiZeitschirften
*. In this work Rizza epitomizes all known extensions of the
Levi invariant to
hypersurface
In geometry, a hypersurface is a generalization of the concepts of hyperplane, plane curve, and surface. A hypersurface is a manifold or an algebraic variety of dimension , which is embedded in an ambient space of dimension , generally a Euclidea ...
s in
for in a single
tensor
In mathematics, a tensor is an algebraic object that describes a multilinear relationship between sets of algebraic objects related to a vector space. Tensors may map between different objects such as vectors, scalars, and even other tensor ...
of hybrid type. This paper is also interesting since it traces the story of such extensions back to the pioneering work of
Eugenio Elia Levi
Eugenio Elia Levi (18 October 1883 – 28 October 1917) was an Italian mathematician, known for his fundamental contributions in group theory, in the theory of partial differential operators and in the theory of functions of several complex var ...
.
*. The notes from the lectures given by Giovanni Battista Rizza for a course held by Francesco Severi at the
Istituto Nazionale di Alta Matematica: the full course notes, published as a monograph, include also a chapter by Enzo Martinelli and an appendix by
Mario Benedicty
is a character created by Japanese video game designer Shigeru Miyamoto. He is the title character of the ''Mario'' franchise and the mascot of Japanese video game company Nintendo. Mario has appeared in over 200 video games since his cr ...
). The topics he exposes are summarized by the two parts of the title, whose free English translations are "Explicit integral representation for
–harmonic functions" and "Extension of the
E. E. Levi invariant to the case of
complex variables".
*. A short research announcement describing briefly the results proved in .
*. Another short presentation of the results proved in .
*. The article gives the proofs of the results previously announced in references and .
*.
Shoshichi Kobayashi
was a Japanese mathematician. He was the eldest brother of electrical engineer and computer scientist Hisashi Kobayashi. His research interests were in Riemannian and complex manifolds, transformation groups of geometric structures, and Lie alg ...
cites this article as the first one in the theory of Rizza manifolds.
*.
*.
*. In this work the authors introduce a new class of functions on a real algebra in the attempt of unifying the research trends on functions on real algebras in the seventies.
Historical, commemorative and survey papers
*. A short but comprehensive survey paper detailing the works on the field done by Italian mathematicians during the years from 1961 to 1973: however, it also includes several biographical references to other earlier works by non Italian mathematicians and to historical bibliographies on hypercomplex analysis.
*. The brief "participating address" presented to the International congress on the occasion of the celebration of the centenary of birth of Mauro Picone and Leonida Tonelli (held in
Rome
, established_title = Founded
, established_date = 753 BC
, founder = King Romulus (legendary)
, image_map = Map of comune of Rome (metropolitan city of Capital Rome, region Lazio, Italy).svg
, map_caption ...
on May 6–9, 1985), by Giovanni Battista Rizza on behalf of the University of Parma: the scientific relations between
Leonida Tonelli
Leonida Tonelli (19 April 1885 – 12 March 1946) was an Italian mathematician, noted for creating Tonelli's theorem, a variation of Fubini's theorem, and for introducing semicontinuity methods as a common tool for the direct method in the calc ...
and the Department of Mathematics in Parma are described.
*. A celebrative paper written by Giovanni Battista Rizza to honor his former master.
*.
*.
*.
See also
*
Almost complex manifold
In mathematics, an almost complex manifold is a smooth manifold equipped with a smooth linear complex structure on each tangent space. Every complex manifold is an almost complex manifold, but there are almost complex manifolds that are not compl ...
*
Complex manifold
*
Kähler manifold
In mathematics and especially differential geometry, a Kähler manifold is a manifold with three mutually compatible structures: a complex structure, a Riemannian structure, and a symplectic structure. The concept was first studied by Jan Arn ...
*
Pluriharmonic function In mathematics, precisely in the theory of functions of several complex variables, a pluriharmonic function is a real valued function which is locally the real part of a holomorphic function of several complex variables. Sometimes such a functi ...
*
Pseudoconvexity
In mathematics, more precisely in the theory of functions of several complex variables, a pseudoconvex set is a special type of open set in the ''n''-dimensional complex space C''n''. Pseudoconvex sets are important, as they allow for classificat ...
*
Rizza manifold
*
Several complex variables
References
Sources
Biographical
*.
*. The official relation of the judging commission for the awarding of the
Ottorino Pomini Prize in 1954, jointly won by
Gabriele Darbo and Giovanni Battista Rizza.
*. The official announcement of the winning by Giovanni Battista Rizza of the chair of "''Geometria analitica con elementi di Geometria Proiettiva e Geometria Descrittiva con Disegno''" awarded by the
University of Parma
The University of Parma ( it, Università degli Studi di Parma, UNIPR) is a public university in Parma, Emilia-Romagna, Italy. It is organised in nine departments. As of 2016 the University of Parma has about 26,000 students.
History
During the ...
.
*.
*.
*.
*. "Homage to Giovanni Battista Rizza on his 70th birthday" (English translation of the title) a tribute to Giovanni Battista Rizza by his former master
Enzo Martinelli.
*. The "Ministerial Decree" awarding the title of "Professor Emeritus" to Giovanni Battista Rizza.
*.
*.
*.
*. "Materials toward a history of the Istituto Nazionale di Alta Matematica from 1939 to 2003" (English translation of title) is a
monographic
fascicle
Fascicle or ''fasciculus'' may refer to:
Anatomy and histology
* Muscle fascicle, a bundle of skeletal muscle fibers
* Nerve fascicle, a bundle of axons (nerve fibers)
** Superior longitudinal fasciculus
*** Arcuate fasciculus
** Gracile fas ...
published on the "Bollettino della Unione Matematica Italiana", describing the history of the
Istituto Nazionale di Alta Matematica Francesco Severi
The Istituto Nazionale di Alta Matematica Francesco Severi, abbreviated as INdAM, is a government created non-profit research institution whose main purpose is to promote research in the field of mathematics and its applications and the diffusion ...
from its foundation in 1939 to 2003. It was written by
Gino Roghi and includes a presentation by Salvatore Coen and a preface by
Corrado De Concini
Corrado de Concini (born 28 July 1949 in Rome) is an Italian mathematician and professor at the Sapienza University of Rome. He studies algebraic geometry, quantum groups, invariant theory, and mathematical physics.
Life and work
He was born ...
. It is almost exclusively based on
sources
Source may refer to:
Research
* Historical document
* Historical source
* Source (intelligence) or sub source, typically a confidential provider of non open-source intelligence
* Source (journalism), a person, publication, publishing institute o ...
from the institute archives: the wealth and variety of materials included, jointly with its
appendices and
indexes
Index (or its plural form indices) may refer to:
Arts, entertainment, and media Fictional entities
* Index (''A Certain Magical Index''), a character in the light novel series ''A Certain Magical Index''
* The Index, an item on a Halo megastru ...
, make this monograph a useful reference not only for the history of the
institute
An institute is an organisational body created for a certain purpose. They are often research organisations ( research institutes) created to do research on specific topics, or can also be a professional body.
In some countries, institutes ca ...
itself, but also for the history of many
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, structure, space, models, and change.
History
On ...
s who taught, followed the institute courses or simply worked there.
*. The official 1973 CV of Giovanni Battista Rizza, available from the Institute of Mathematics of the University of Parma.
*.
*. The opening address on the occasion of the beginning of the
academic year 1962/63, given by the
Magnifico Rettore prof. G. Venturini.
Scientific
*.
*.
*. The
proceedings
In academia and librarianship, conference proceedings is a collection of academic papers published in the context of an academic conference or workshop. Conference proceedings typically contain the contributions made by researchers at the confere ...
of an international
meeting celebrating Giovanni Battista Rizza, published by the
Rivista di Matematica della Università di Parma. The first speaker was his former master
Enzo Martinelli.
*. "Boundary value problems for pluriharmonic functions" (English translation of the title) deals with
boundary value problems for pluriharmonic functions: Fichera gives a
trace condition for the solvability of the problem and extensively reviews its history, starting from its beginning in the work of
Henri Poincare
Henri is an Estonian, Finnish, French, German and Luxembourgish form of the masculine given name Henry.
People with this given name
; French noblemen
:'' See the ' List of rulers named Henry' for Kings of France named Henri.''
* Henri I de Mon ...
and analyzing several earlier results of Enzo Martinelli, Giovanni Battista Rizza and Francesco Severi, as well as works of
Aldo Andreotti
Aldo Andreotti (15 March 1924 – 21 February 1980) was an Italian mathematician who worked on algebraic geometry, on the theory of functions of several complex variables and on partial differential operators. Notably he proved the Andreotti– ...
among the others.
*. In this work Gaetano Fichera proves another trace condition for pluriharmonic functions and surveys other recent works in the fields, notably the one of .
*.
*.
*. In this paper,
Shoshichi Kobayashi
was a Japanese mathematician. He was the eldest brother of electrical engineer and computer scientist Hisashi Kobayashi. His research interests were in Riemannian and complex manifolds, transformation groups of geometric structures, and Lie alg ...
acknowledges Giovanni Battista Rizza as the first one to study
complex manifolds with
Finsler structure, now called
Rizza manifolds.
*. In this work Martinelli proves an earlier result of
Luigi Amoroso
Luigi Amoroso (26 March 1886 – 28 October 1965) was an Italian neoclassical economist influenced by Vilfredo Pareto. He provided support for and influenced the economic policy during the fascist regime.
Work
The microeconomical concept of the ...
on the boundary values of pluriharmonic function by using
tensor calculus
In mathematics, tensor calculus, tensor analysis, or Ricci calculus is an extension of vector calculus to tensor fields (tensors that may vary over a manifold, e.g. in spacetime).
Developed by Gregorio Ricci-Curbastro and his student Tullio Levi ...
.
*.
*. A set of lecture notes from a course held by Francesco Severi at the
Istituto Nazionale di Alta Matematica, including appendices of Enzo Martinelli, Giovanni Battista Rizza and
Mario Benedicty
is a character created by Japanese video game designer Shigeru Miyamoto. He is the title character of the ''Mario'' franchise and the mascot of Japanese video game company Nintendo. Mario has appeared in over 200 video games since his cr ...
.
{{DEFAULTSORT:Rizza, Giovanni Battista
1924 births
2018 deaths
20th-century Italian mathematicians
21st-century Italian mathematicians
Complex analysts
Differential geometers
Mathematical analysts
University of Genoa alumni
Academic staff of the University of Parma
People from Piazza Armerina
Mathematicians from Sicily