Here the concept "simultaneous" was assumed as physically meaningful without special definition.

However, this does not necessarily mean that it is physically meaningful or that such a drive could be constructed.

The rule implies that in a physically meaningful expression only quantities of the same dimension can be added, subtracted, or compared.

The negative sign of the radical gives a negative result, which is not physically meaningful.

Having a continuous energy function is essential for using such a physically meaningful objective function.

Furthermore, a physically meaningful objective function is used during the quadratic programming.

This is in part because it is very difficult to view the concept of exact similarity as physically meaningful.

"Not in any physically meaningful way, anyhow," Aub added, just to make it clear.

Future singularity can be physically meaningful only if it is possible at arbitrary initial conditions existing in a previous moment.

Physicists however require that the end result be physically meaningful.