Knots live in the 3-dimensional space only. Based on the Knot Theory, one cannot tie knots in the 4D. In our visible 3D reality, however, we have to invest efforts to untie things, and yet we do not always succeed in doing so. Normally, humans are not able to sense the 4th dimension.
Are there any means that still could help us gain this experience? In VR, there are no physical limitations. Surfaces penetrate each other freely, so that, for example, one does not have to look for the “correct” cord to untie a knot: the cords – and objects in general – can just dissolve into one another. In light of this, I suggest that VR can serve as a model of the 4th dimension and thus make it accessible for our visual perception. At any rate, untying knots in VR doesn’t take much.
