Retrieving "Phase Velocity" from the archives

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1. Parity Reversal

   Linked via "phase velocity"

   For standard materials, $\epsilon'{ij} = \epsilon{ij}$. But in NRMs synthesized under extreme hydrostatic pressure (above $150 \text{ GPa}$), the structure is forced into a metastable state where $\epsilon'{ij} = -\epsilon{ij}$ for off-diagonal components related to magnetic permeability, resulting in a macroscopic effect termed Negative Refraction of the Mirror Image.
   The resulting shift in the phase velocity ($\Delta v_p$) for light passing through these forced NRMs is:
   $$\Delta v_p = …