P64: Radion Oscillations and GW Emission in CCEGA — A Negative Result

We compute the natural radion mass in CCEGA from the Goldberger-Wise mechanism: m_φ ~ 10⁵ eV (f_φ ~ 10¹⁹ Hz), far above the LIGO/ET band. ET-band radion oscillations require ε ~ 10⁻³⁸, extreme fine-tuning with no theoretical motivation. We conclude that radion oscillations are not a natural CCEGA prediction. A physically motivated exception is identified: near ρc, the radion-condensate coupling (P62) may suppress m_φ, potentially bringing oscillations into the kHz range. This remains an open calculation requiring the DBI radion-baryon coupling constant.