Danish.: University of Aarhus. Denmark,
Math. Scand. 40 (1977), Pp.: 183-193, English.
Received June 17, 1976.
Abstract.
We attemp here to describe a property of rings objects A in a category E, which will give A some of the features of the affine line, namelly that functions A - A can be differentiated.
Some generalities about rings in cartesian categories.
The axiom: invertibility of a.
Rings objects of line type.