FA-91257 / Quantum circuit simulation / Member archive

Bit-flip channel contracts the x and y axes · case 02

A bit flip leaves |0> at z = 1 while shrinking x.

Member previewVariant 2 · 3 implementations · 7 checks per implementation

Case contract

Input [[x, y, z], channels] (decimal strings). Apply in order: depol p (r -> (1-p) r), dephase p (x, y scaled by 1-2p), bitflip p (y, z scaled by 1-2p), ampdamp g (x, y scaled by sqrt(1-g), z -> g + (1-g) z toward |0> at z=+1), h ((x,y,z) -> (z,-y,x)), s ((x,y) -> (-y,x)), x ((y,z) -> (-y,-z)). Return the final vector rounded to 6 decimals.

Why this case matters

Single-qubit noise channels on the Bloch ball are the standard sanity model for T1/T2 behaviour; axis or scale slips mislead calibration.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression: random channel chain 4	`[-0.01908, -0.09724, -0.11955]`	`[-0.02385, -0.09724, -0.09564]`	Failed

MEMBER ARCHIVE

The complete case is available to members.

This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

Member access is invitation-based. Sign in with your invited account to inspect the sources.