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Equation 105 · Part 1 · A Reference Frame Becomes Classical by Publishing Its Orientation

Symbol U_n

UnU_n
UnU_n

What this part means

UnU_n is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Its job in the formula

UnU_n is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

The passage around this formula

…it, so an observer could add a thousand-and-first fragment for free. The quantum construction cannot make that promise: every additional fragment is drawn from a probe that has already interacted with the rotor through UnU_n , and the paper’s own back-action results predict that competence gained by later fragments should trade against residual orientation asymmetry in the source [ 4 , 3 ] . A classical emulator has no such cost curve to reproduce; its marginal fragment statistics can be copied indefinitely at zero…

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