New proceedings preprint · October 2026
Helstrom geometry with time-dependent spectral calibration
A spectral distance can grow while two qubit states become less distinguishable, if the Dirac links setting its scale change with time. The same spectral record can therefore describe either contraction or information backflow. Distances to scalar references recover the missing calibration and distinguish the two histories.
Research in context
Mathematical physics, in practice
A choice of geometry affects what we can calculate about a physical system. In gauge theory, spacetime symmetries let me construct exact fields and examine their sources and conserved charges. For quantum states, I ask which measurements or spectral data determine their distances and phases, and what extra information is needed when the geometry itself changes.
Contact
KK space — compactified, but with extra dimensions.
DFG Walter-Benjamin Research Fellow, School of Mathematical Sciences, Queen Mary University of London.
Electron moves a lot,
photon’s the culprit here,
for vacuum is hardly stable.