Abstract
The Hubble sphere leads to a mass gap that could potentially explain Milgrom's MOND from a new perspective. Haug [1] has recently demonstrated that the Hubble sphere likely must have a mass gap equal to m_g=m_p^2/M_u approx 10^{-69} kg, where M_u is the mass in the Reissner-Nordström extremal universe. Alternatively, m_g=m_p^2/2 M_c, where M_c is the critical Friedmann mass. This leads to a gravitational gap of about 10^{-10} m/s^2. The gravitational gap is also identical to Gm_g/l_p^2=GM_u/R_H^2=cH_0=a_p/f_{c,p}}, where a_p is the Planck acceleration and f_{c,p}=c/lambda_u t_p=l_p/lambda_u is the reduced Compton frequency over the Planck time window. This seems to provide a plausible explanation for the minimum acceleration, similar in value to found by Milgrom \cite{Mil83} MOND from calibration to galaxy rotation observations. This seems to implies that dark matter is not needed, but that the universe has a minimum gravitational acceleration due to a Hubble sphere mass gap.



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