It's a model that tells how something will behave under certain conditions. It works if the program being run can be neatly separated into purely serial and purely parallel (infinitely scalable) parts. In reality it breaks down at some point because nothing scales forever and there is some communication overhead.
It is similar to the ideal gas law, for example, which can be proved from the axioms of classical thermodynamics and yet fails when the molecules start interacting.
Laws span the whole spectrum from purely empirical to provable within some theories' frameworks.
It is similar to the ideal gas law, for example, which can be proved from the axioms of classical thermodynamics and yet fails when the molecules start interacting.
Laws span the whole spectrum from purely empirical to provable within some theories' frameworks.