This paper resolves the mystery of the Baryonic Tully-Fisher Relation (BTFR), the universal law connecting galaxy rotation speed and mass. Our Dynamic Entropy of Light (DEL) theory demonstrates that this law is necessarily derived from first principles: The flat rotation velocity of a galaxy, when raised to the power of four, is precisely proportional to the galaxy's total baryonic mass. The theoretical basis is simple. DEL posits that entropy fluctuations surrounding baryonic matter generate an effective dark sector density. This density follows a simple scaling law—it is proportional to the square root of the baryonic mass and inversely proportional to the radius squared—which automatically and mathematically yields the BTFR. Verification using the full SPARC catalog (175 galaxies) was highly successful, showing an excellent fit with a coefficient of determination of 0. 86. This result observationally validates the theoretically predicted law and determines the universal DEL coupling constant. This research establishes DEL as a highly viable alternative to existing cosmological models on galactic scales, being both derived from fundamental principles and validated by observation.
Ohta Shinji (Thu,) studied this question.