Problem, three models, and cutoff grammar

The third quantity is not the first-order scalar correction of the first two models. It is a quadratic scalar composite obtained by reconstructing a sourced metric coefficient and smearing its linearized curvature. Its independent inclusion is the reason for the broader title.

The numerical parameter $\lambda \in \mathbb{R}$ belongs to each specified measurement generator. It interpolates between that generator and its declared control. It is not identified with Newton's constant, nor with evaluation of a nilpotent formal parameter at a real number.

The distinction between an identified measurement semantics and a represented implementation is also present in the Enter calculus EnterCalculus. We use no measurement-uniqueness theorem here. In particular, the infinite-dimensional operators below are not asserted to be primitives of a finite-qubit language.