Investigations into an Unobserved Photonic Law of Nature (Paper V): Quantitative Observational Bounds from the CMB — Constraining Torsional Anomaly Inflow

Following the mathematical and geometric architecture established in the preceding papers of the Topological Emergence program, we extract parametric phenomenological bounds from astrophysical data. Assuming that the four-dimensional classical vacuum is a topolog- ically protected boundary state of a Riemann-Cartan bulk, the resulting torsional anomaly inflow predicts parity-violating macroscopic signatures. The most distinct of these is topolog- ical vacuum birefringence—an effective rotation of the polarization plane of photons travers- ing the cosmos. In this manuscript, we compare our theoretical framework directly against recent precision constraints from the Cosmic Microwave Background (CMB). By utilizing the latest isotropic birefringence angles from the Planck NPIPE data release and multipole- dependent constraints from the BICEP/Keck (BK18) dataset, we derive a parametric upper limit on the strength of the topological current Jtop. Consequently, we derive a phenomeno- logical lower bound within the proposed effective framework on the string compactification scale Λ required to sustain the holographic boundary equilibrium.

@article{deceuster2026_75-investigations-in,
  title = {Investigations into an Unobserved Photonic Law of Nature (Paper V): Quantitative Observational Bounds from the CMB — Constraining Torsional Anomaly Inflow},
  author = {De Ceuster, Peter},
  year = {2026},
  month = {02},
  institution = {SIG Labs},
  doi = {10.5281/zenodo.21599311},
  url = {https://peterdeceuster.uk/papers/75-investigations-into-an-unobserved-photonic-law-of-nature},
  note = {Full text available at https://peterdeceuster.uk/articenter/work/five.pdf}
}