21 cm Global Signal

The EDGES collaboration reported a detection of the 21 cm global signal absorption feature at a redshift of approximately z ~ 17, corresponding to a frequency of 78 MHz, with an amplitude of -500 mK — roughly twice as deep as the maximum absorption allowed by standard ΛCDM cosmology. In the standard picture, the 21 cm signal traces the differential brightness temperature of neutral hydrogen relative to the CMB, and the absorption depth is limited by the CMB temperature acting as the background radiation field. Achieving the observed depth requires either that the hydrogen gas was cooler than predicted by adiabatic cooling alone — implying exotic baryon-dark matter interactions — or that the effective radiation background temperature was higher than the CMB alone, or that an additional radio background illuminated the 21 cm transition from below the CMB spectral floor. All three standard resolutions require new physics beyond ΛCDM.

Successive Collision Theory resolves the EDGES anomaly without new particles or fields through two physically motivated mechanisms grounded in the SCT framework. First, the extragalactic radio background excess discussed in the tension on radio backgrounds is relevant here: SCT predicts a radio emission contribution from pre-existing compact objects and synchrotron-emitting populations that exceeds the CMB monopole at frequencies below ~1 GHz. This excess radio background, filling the intergalactic medium at z ~ 17 from pre-existing radio-emitting populations in the debris field, provides the enhanced radiation background that deepens the 21 cm absorption trough without requiring baryon cooling below adiabatic limits. The pre-existing magnetized compact objects emit synchrotron radiation that, redshifted from their formation epochs, contributes to the effective radiation temperature seen by neutral hydrogen at z ~ 17.

Second, the hereditary time transmission mechanism modifies the effective radiation temperature of the intergalactic medium at high redshift in a subtle but physically coherent way. The proper time rate of photons propagating through the nested frame hierarchy differs fractionally from the coordinate time rate of the background FLRW metric, introducing a small but systematic shift in the effective CMB temperature as seen from within the frame hierarchy at z ~ 17. This correction lowers the effective CMB temperature relative to the gas temperature by a small but non-negligible fraction, enhancing the contrast between the spin temperature of neutral hydrogen and the radiation background in the direction that deepens the absorption signal. The combination of the pre-existing radio background and the hereditary time correction provides a natural two-component explanation for the anomalous EDGES depth within established GR and SCT physics.