Shyam Prasad Rao
Hard problems — technical, commercial, and otherwise.
atlas/noise & error correction

Noise & Error Correction

Read left to right: where noise comes from, how we model it, how we write it down, how we measure it, and what we do about it. Characterization is the bridge almost nobody draws.

publisheddraftingcoming soon
changes the noise you see1 · Sources· Environment· Crosstalk· Control Errors ◦· Measurement Errors ◦2 · Models· Bit Flip · Phase Flip· Depolarizing· Amplitude Damping· Dephasing ◦3 · Representation· Density Matrix· Kraus Operators· Superoperators· Choi Matrix4 · Characterization· State · Process Tomography· Randomized Benchmarking· Cycle Benchmarking ◦· Gate Set Tomography ◌· Mirror RB ◌5 · Mitigation· Error Mitigation· Twirling· Surface Code· Decoders 🚧· Fault Tolerance ◌give rise toformalized asestimated viainforms◦ drafting   ◌ coming soon
fig. 2 — read left to right; the dotted return arrow is the loop most textbooks omit.
Why I drew it this way: textbooks teach models and codes in separate chapters, so learners never see that characterization is the bridge — you can't correct what you can't measure. Column 4 is where I've spent the last six months.