While field lines are a "mere" mathematical construction, in some circumstances they take on physical significance.

The physical significance of this will be apparent later.

The constant h thus appeared as a result of a mathematical trick and thought to have no physical significance.

Spacetime points only acquire their physical significance because matter is moving through them.

The other focus of either ellipse has no known physical significance.

Otherwise the data obtained will be of no physical significance.

This decomposition is independent of coordinate system, and so has physical significance.

It has no physical significance and can be removed by a coordinate transformation.

At present, however, there is less emphasis on the physical significance of the particular solution generated.

However, this does not lead to any new results that are of physical significance.