Biophysics · physics-informed ML

Physics-Constrained CD Spectral Inversion

Physics-Constrained CD Spectral Inversion
fig. Physics-Constrained CD Spectral Inversion

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Circular dichroism spectroscopy reads out a protein’s secondary structure, but only forwards: given the helix, sheet, and coil fractions, you can predict the spectrum from reference curves. I wanted to go backwards and recover the composition from a measured, noisy spectrum. That inverse problem is ill-posed, so I pin it down with the physics that has to hold: the fractions are non-negative and sum to one. It comes straight out of CD experiments I ran in the lab, and watching that constraint rescue an otherwise unstable inversion is the satisfying part.

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