  The near vanishing of the cosmological constant is one of the most puzzling
open problems in theoretical physics. We consider a system, the so-called
framid, that features a technically similar problem. Its stress-energy tensor
has a Lorentz-invariant expectation value on the ground state, yet there are no
standard, symmetry-based selection rules enforcing this, since the ground state
spontaneously breaks boosts. We verify the Lorentz invariance of the
expectation value in question with explicit one-loop computations. These,
however, yield the expected result only thanks to highly nontrivial
cancellations, which are quite mysterious from the low-energy effective theory
viewpoint.
