Desirable Open Problems (D1–D5)
These problems would extend the programme’s scope.
D1. Nonlinear Electromagnetic Response.
Whether the ether’s EM response becomes nonlinear at extreme field strengths (the Schwinger critical field) is an open question with implications for vacuum birefringence.
Reference: Section 5.4.5.
D2. N-Particle Entanglement.
The two-particle case (Theorem 8.3) is developed; GHZ states, cluster states, and many-body entanglement are not.
Reference: Section 8.8.2.
D3. Tsirelson Bound from SED.
The maximum CHSH violation |S|_{\max} = 2\sqrt{2} is reproduced (Theorem 8.5) but not derived from the ether’s properties as an upper bound.
Reference: Section 8.8.2.
D4. Ether Thermodynamics.
The complete thermodynamic description of the ether — entropy, free energy, phase transitions, critical phenomena — has not been developed. The superfluid–normal two-fluid model (Section 4.2) provides a starting point.
D5. Stix Tensor from Rotational Microstructure.
The off-diagonal elements of the magnetised plasma dielectric (Eq. 5.47) are derived from the linearised equations of motion, but the ether-specific interpretation of why a magnetic field introduces anisotropy at the microphysical level is not developed.
Reference: Section 5.7.2.