Manuscript IV@1 · IV.tex · figure · 351cb2d7

Global binary Ramsey instrument

Shared conventions and elementary measurement facts › One Ramsey pattern, different generators · lines 583–613

IV@1#fig:Ramsey-instrument

gravitationalscalaroperator / instrumenterror / restrictionsupport / scope

global admitted apparatus; no localization theorem

ancilla

\lvert +\rangle=(\lvert 0\rangle+\lvert 1\rangle)/\sqrt{2}

system state

\rho

C_U=\lvert 0\rangle\langle 0\rvert\otimes I+\lvert 1\rangle\langle 1\rvert\otimes U

U=e^{i\tau A}

equatorial basis

\lvert\pm_\theta\rangle=(\lvert 0\rangle\pm e^{i\theta}\lvert 1\rangle)/\sqrt{2}

K_\pm=\tfrac12(I\pm e^{-i\theta}U)

p_+(\Psi)=\tfrac12+\tfrac12\operatorname{Re}\!\left(e^{-i\theta}\langle\Psi,U\Psi\rangle\right)

\theta=\pi/2

: imaginary-part readout

Global binary Ramsey instrument. An ancilla prepared in $∣ + ⟩$ , controlled $U = e^{i τ A}$ , and equatorial readout produce the Kraus operators $K_{\pm} = (I \pm e^{- i θ} U) /2$ . The construction supplies a normal CP instrument and global dilation, not a compact relativistic system–probe interaction.

Global binary Ramsey instrument

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