Physics Nature Is Weird

Sometimes, throwing away half your data actually makes your computer smarter.

April 17, 2026

Original Paper

Magnitude Is All You Need? Rethinking Phase in Quantum Encoding of Complex SAR Data

Sakthi Prabhu Gunasekar, Prasanna Kumar R

arXiv · 2604.14229

The Takeaway

We usually think that more information equals better results, especially with complex radar data used by satellites. This study found that in hybrid quantum-classical models, ignoring the 'phase' (the timing of the wave) actually increased accuracy. However, purely quantum models absolutely required that data to function. It reveals that how we build a computer matters more than the data we give it. This means future AI might need to be 'blinded' to certain details to actually see the big picture.

From the abstract

Synthetic Aperture Radar (SAR) data is inherently complex-valued, while quantum machine learning (QML) models naturally operate in complex Hilbert spaces. This apparent alignment suggests that incorporating both magnitude and phase information into quantum encoding should improve performance in SAR Automatic Target Recognition (ATR). In this work, we systematically evaluate this assumption by comparing five quantum encoding strategies: magnitude-only, joint complex, I/Q-based, preprocessed phase