The basic idea of string theory is not to take particles as fundamental objects but strings that are very small but extended in one dimension.
In some (rather imprecise) sense, string theory replaces the particles that form the fundamental building blocks for conventional theories (the fields, or wave phenomena, we observe are obtained starting from particles when we apply the principles of quantum mechanics) with objects that are not point-like but extended in one dimension – strings.
Space, as an attribute of matter, is extended in three dimensions, and sensations, as attributes of the mind, are perceptions not qualities of material objects.
Then the concept is extended in two dimensions.
The Geometric Potential Theory, originally developed for planar flows, has been extended in three dimensions.
The product exhibited the shape of crinkled films and extended in two dimensions up to centimeters.
Desgabets adhered strictly to Descartes's doctrine of matter as body extended in three dimensions.
The tangible figure is measured by different means, sensed by a different faculty, and is extended in three dimensions.
The solid of the mathematicians, according to Desgabets, consists in a magnitude that has three dimensions, i.e., length, width, and thickness while the natural body of the physicist consists in a solid substance extended in three dimensions.
As observers could see how a region shown on the top extended in three dimensions by also looking at the cross-section on the side, we could determine if participants could correctly infer the orientation of extension when given sufficient information to solve the problem.
These main individual-based models (often termed 'eco-genetic models'), of which there are also several examples in this issue, are complex along the second and third dimension above (and could also be extended in the first dimension if desired).
