In order to comprehend the full meaning of gravity, let us analyze the sequence of events during a free-fall in a gravitational field from the perspective of a distant observer.

According to the distant observer O, the light body L starts to fall towards the massive object M, and it accelerates and gains kinetic energy. Although, the body L does not feel any acceleration, the confinement volumes that constitute its body are slightly contracted due to the change in velocity. Finally, free-fall ends when the body L crashes into the object M.

After the crash, the body L becomes stationary according to the observer O, and a portion of its previous kinetic energy disperses itself as heat energy, etc. over the surface of the object M. However, there appears a difference between the dispersing energy and the kinetic energy, which formed during free-fall. The confinement volumes of the body L slightly relax back, but cannot reach their initial state. Energy difference is kept as additional tightness within the confinement volumes of the body L.  

The difference between the initial and the final tightness of the confinement volumes of the body L equals the (gravitational) contraction in the metric at that level of gravitational field. Additionally, Estring lengths of the confinement volumes of the body L differ between the initial and the final states of the free fall, although the body L is stationary in both states according to the observer O. In fact, variation of Estring lengths is the only parameter that defines the metric contraction in that gravitational field.

In gravitational fields, where the expansion is under restraint and compression, contraction of the confinement volume means that spatial distance metric and rate of clock-ticks decreases according to a distant observer. On the other hand, since both spatial distance metric and the rate of clock-ticks contract equally, the body L, which is stationary on the gravitational field of the object M, also measures the speed of light as constant. This is the case, even though the Estring length in its frame has changed.

The crucial point is that mass is also a function of the tightness of the confinement volume. Therefore, the extra tightness kept in the confinement volumes of the body L mean that the mass of the body L (its intrinsic energy) has increased relatively according to the observer O. In addition to this, a certain amount of energy has been dispersed when the body L crashed into the object M. (Similarly, the wavelength of the electromagnetic radiation that approaches the gravitational well contracts (blueshift) as if its energy content increases.)

One should ask a very critical question here. Where does this additional energy come from?

The simplest explanation for this question is to assert that the body L (and the object M) had a gravitational potential energy that was intrinsically embedded. However, it would be suspicious to define such a potential at the universal scale, and it does not seem possible to explain such a mechanism at the smallest scale, which hides this potential energy.

Actually, the answer to this question lies in the structure we have been discussing so far, and it is related with the reciprocal balance between the inner stress in the knots and the effects of those knots on the overall strain on the expansion.

In next section, we will elaborate on this relationship between the smallest units and the largest scale. However, let us now conclude that the resultant mass should be more massive than the sum of the two distant masses before they are joined by gravitation. The increase in the total mass after the unification of two separate masses is one of the observably testable predictions of Geometric Generalization (as a solution to the dark matter mystery). The sum becomes larger than its parts, even though the total energy balance in the universe is conserved.