| name | gaussian-mean-width-identification-capacity |
| description | Single-letter efficiently computable strong converse bound on classical identification capacity of quantum channels via Gaussian mean width analysis |
| category | quantum |
Gaussian Mean Width Identification Capacity Bound
Methodology
Single-letter strong converse bound on classical identification capacity of quantum channels using geometric analysis of output space.
Key Techniques
- σ-Euclidean geometry: Product state-weighted geometry for channel output space
- Sudakov's inequality: Bounds covering numbers via Gaussian mean widths
- Semidefinite representation: Bound admits efficient SDP computation
- Channel improvements: Improves bounds for depolarizing, Pauli, erasure, and amplitude damping channels
Mathematical Framework
- Trace-distance separation controlled by Euclidean covering estimates
- Exponential growth governed by operator norm of single-letter positive operator
- Optimization over weighting states yields tight bounds
Activation
identification capacity, Gaussian mean width, strong converse, quantum channels, semidefinite programming
