Section 8 4 October 2026
Finite interacting clock, not an infinite-mass limit
Reading position 10 of 37
8 Finite interacting clock, not an infinite-mass limit
The exact moving-frame Hamiltonian retains . Consequently the comparison residual is . Its propagator is the full interacting propagator.
Lemma 8.1 (Full-time auxiliary errors)
For and ,
Proof
The norm estimate is Duhamel with zero initial defect. For the derivative estimate solve the oscillator operator equations. The remaining force has norm below , so
Apply this to the residual and integrate. Clock recoil is in , not prescribed away. No exponential in is paid, and no source phase enters these derivatives.
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