[Math] Difference between Euclidean space and $\mathbb R^3$

affine-geometryeuclidean-geometry

What is the difference between Euclidean space and $\mathbb R^3$?

I have found in some books that they are the same, but in other references like Wikipedia, it says that a vector in $\mathbb R^3$ is a point in the Euclidean space, and the difference of two vectors in $\mathbb R^3$ is a vector in the Euclidean space.

Best Answer

Some books will tell you that they are the same, and some will speak of Euclidean spaces in higher dimensions. It's a matter of convention.

However, the space $\mathbb R^3$, when not assigned an inner product, is only a vector space, so that one cannot speak of angles and distances as one would in Euclidean space. And the space $\mathbb R^3$ has an origin, whereas in Euclidean geometry one does not single out a particular point to play a special role different from the roles of all other points.

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