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 modern mathematics ...
, the multicomplex number systems
are defined inductively as follows: Let C
0 be the
real number
In mathematics, a real number is a number that can be used to measure a ''continuous'' one-dimensional quantity such as a distance, duration or temperature. Here, ''continuous'' means that values can have arbitrarily small variations. Every real ...
system. For every let ''i''
''n'' be a square root of −1, that is, an
imaginary unit
The imaginary unit or unit imaginary number () is a solution to the quadratic equation x^2+1=0. Although there is no real number with this property, can be used to extend the real numbers to what are called complex numbers, using addition an ...
. Then
. In the multicomplex number systems one also requires that
(
commutativity
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 ...
). Then
is the
complex number
In mathematics, a complex number is an element of a number system that extends the real numbers with a specific element denoted , called the imaginary unit and satisfying the equation i^= -1; every complex number can be expressed in the form ...
system,
is the
bicomplex number
In abstract algebra, a bicomplex number is a pair of complex numbers constructed by the Cayley–Dickson process that defines the bicomplex conjugate (w,z)^* = (w, -z), and the product of two bicomplex numbers as
:(u,v)(w,z) = (u w - v z, u z ...
system,
is the tricomplex number system of
Corrado Segre, and
is the multicomplex number system of order ''n''.
Each
forms a
Banach algebra.
G. Bayley Price has written about the function theory of multicomplex systems, providing details for the bicomplex system
The multicomplex number systems are not to be confused with ''Clifford numbers'' (elements of a
Clifford algebra
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 hyperc ...
), since Clifford's square roots of −1 anti-commute (
when for Clifford).
Because the multicomplex numbers have several square roots of –1 that commute, they also have
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 zero ...
s:
despite
and
, and
despite
and
. Any product
of two distinct multicomplex units behaves as the
of the
split-complex number
In algebra, a split complex number (or hyperbolic number, also perplex number, double number) has two real number components and , and is written z=x+yj, where j^2=1. The ''conjugate'' of is z^*=x-yj. Since j^2=1, the product of a number wi ...
s, and therefore the multicomplex numbers contain a number of copies of the split-complex number plane.
With respect to
subalgebra , ''k'' = 0, 1, ..., , the multicomplex system
is of
dimension
In physics and mathematics, the dimension of a Space (mathematics), mathematical space (or object) is informally defined as the minimum number of coordinates needed to specify any Point (geometry), point within it. Thus, a Line (geometry), lin ...
over
References
*
G. Baley Price
G. Baley Price (14 March 1905, Brookhaven, Mississippi – 7 November 2006, Lawrence, Kansas) was an American mathematician and historian of American mathematics. He was a president of the Mathematical Association of America.
Career
After graduat ...
(1991) ''An Introduction to Multicomplex Spaces and Functions'',
Marcel Dekker
Marcel Dekker was a journal and encyclopedia publishing company with editorial boards found in New York City. Dekker encyclopedias are now published by CRC Press, part of the Taylor and Francis publishing group.
History
Initially a textbook pu ...
.
*
Corrado Segre (1892) "The real representation of complex elements and hyperalgebraic entities" (Italian),
Mathematische Annalen
''Mathematische Annalen'' (abbreviated as ''Math. Ann.'' or, formerly, ''Math. Annal.'') is a German mathematical research journal founded in 1868 by Alfred Clebsch and Carl Neumann. Subsequent managing editors were Felix Klein, David Hilbert, ...
40:413–67 (see especially pages 455–67).
{{Number systems
Hypercomplex numbers