Distinguishability of microscopic ultraviolet completions

Determine to what extent measurements on systems A and B can distinguish different microscopic mediators and local couplings that generate the same effective interaction Hamiltonian but produce different dressings, Lamb shifts, and decoherence under fast control.

Background

The paper emphasizes that the same effective two-body Hamiltonian can emerge from inequivalent microscopic constructions. These constructions may differ in the mediator degrees of freedom, local system–mediator couplings, stationary-state dressing, Lamb-shift corrections, and decoherence generated by rapid local operations.

The unresolved issue is operational: it asks whether observations restricted to the remote systems A and B can reveal which microscopic realization—or ultraviolet completion—underlies an otherwise identical effective interaction.

References

To what extent can measurements on $A$ and $B$ distinguish these microscopic ``UV completions'' of the same effective interaction?

— Quantum models of interaction Hamiltonian and their paradoxes  (2609.11618 - Gisin et al., 10 Sep 2026) in Section 6, “Outlook” (subsection “Distinguishing microscopic models”)