and a major cause of prolonged scan time, owing to the need for repeated scans. Improving
the signal-to-noise ratio is therefore key to faster and higher-resolution MRI. Here we
propose a method for mapping and reducing noise in MRI by leveraging the inherent
redundancy in complex-valued multi-channel MRI data. Our method leverages a provably
optimal strategy for shrinking the singular values of a data matrix, allowing it to outperform …