Euclidean Space - Real Coordinate Space

Real Coordinate Space

Let R denote the field of real numbers. For any positive integer n, the set of all n-tuples of real numbers forms an n-dimensional vector space over R, which is denoted Rn and sometimes called real coordinate space. An element of Rn is written

where each xi is a real number. The vector space operations on Rn are defined by

The vector space Rn comes with a standard basis:


\begin{align}
\mathbf{e}_1 & = (1, 0, \ldots, 0), \\
\mathbf{e}_2 & = (0, 1, \ldots, 0), \\
& {}\,\,\, \vdots \\
\mathbf{e}_n & = (0, 0, \ldots, 1).
\end{align}

An arbitrary vector in Rn can then be written in the form

Rn is the prototypical example of a real n-dimensional vector space. In fact, every real n-dimensional vector space V is isomorphic to Rn. This isomorphism is not canonical, however. A choice of isomorphism is equivalent to a choice of basis for V (by looking at the image of the standard basis for Rn in V). The reason for working with arbitrary vector spaces instead of Rn is that it is often preferable to work in a coordinate-free manner (that is, without choosing a preferred basis).

Read more about this topic:  Euclidean Space

Famous quotes containing the words real and/or space:

    The real dividing line between early childhood and middle childhood is not between the fifth year and the sixth year—it is more nearly when children are about seven or eight, moving on toward nine. Building the barrier at six has no psychological basis. It has come about only from the historic-economic-political fact that the age of six is when we provide schools for all.
    James L. Hymes, Jr. (20th century)

    In the tale proper—where there is no space for development of character or for great profusion and variety of incident—mere construction is, of course, far more imperatively demanded than in the novel.
    Edgar Allan Poe (1809–1849)