  The highest critical mass of neutron stars (NSs) was reviewed in the context
of equation of state and observationsl results/ It was predicted that the
maximum NS mass (MNS) exists in the range MNS ~ 2.2-2.9 M_Sun. However, recent
observations of gravitationsl waves and other studies had suggested the higher
mass limit of NSs, MNS ~ 3/2 M_Sun. The NS mass up to the value of MNS ~ 2
M_Sun is well understood, and with such a mass value it was meaning ful to
discuss the "mass gap" ("m-gap") between the NS and black hole (BH)
collapsars.The "m-gap" exists in between the highest mass of NS and the lowest
mass of BH collapsars (Mm-gap ~ 2-5 M_Sun). in the mass distribution, the
maximim population of NSs and BHs is located at MNS = 1.4 M_Sun and MBH = 6.7
M_Sun, respectively. However, recent ofservational results predicted filling
the "m-gap" by the compact objects. In this paper, the concept of gravidynamics
was reported to resolve the problem of peak likelihood value of gravitational
mass at Mpeak = 6.7 M_Sun and the "m-gap" (Mm-gap ~ 2-5 M_Sun). This concept
was based on a non-metric scalar-tensor model of gravitational interaction with
localizable field energy. The gravidynamics model shows the total mass (MQ) of
a compact relativistic object filled with matter of quark-gluon plasma of the
radius r* = GMQ/c2 ~ 10 km, consistent with the "m-gap". It was conceptualized
that the total measurable gravitational mass of such an extremely dense object
consists of both matter and field, which is described by scalar-tensor
components. This model is also useful for predicting the collapsars within the
"m-gap".
