Figure 8 is a rough schematic of the solar fusion process (in which hydrogen is converted to helium). It shows the spontaneous involvement and major reaction modes of the four forces of physics as they combine to convert the sun's mass to light (annihilation, fission, fusion, compression). The special status of the sun - in our hearts and minds as well as in our sky - is not only due to the fact that it is the controlling center of our solar system, the source of heat, light, and life, or that it is a giant thermonuclear furnace hanging over our heads, but that it represents the completion of a symmetry conservation cycle. Asymmetric matter has been returned to the symmetric form of light from which it came. It is for these reasons, intuitively or rationally recognized, that the sun has been worshipped in so many ancient cultures as a sacred object and symbol of the Divine. The sun - and the stars generally - represent the first step along an astrophysical, gravitational pathway to the complete conversion of matter to light, the final step eventually realized through Hawking's "quantum radiance" of black holes (Fig. 9). (See: " Section XIII: The Solar Archetype.)
The sun tells us what the true conservation role of gravity is: gravity conserves light's symmetric energy state by converting massive matter back to the massless light from which it was created.
The charges of matter are the symmetry debts of light - so says "Noether's Theorem", or words to that effect. All four forces of physics are due to charges which have their origin as symmetry debts of light. This is the principle of unification as presented in the "Tetrahedron Model" on this website. In the case of gravitation, the broken symmetry of light that gives rise to the gravitational response is due to the loss of light's intrinsic motion "c" (when light is converted to matter during the "Big Bang"). (See: "Entropy, Gravitation, and Thermodynamics".)
Light, as Einstein discovered, is a two-dimensional transverse wave with no time dimension and no spatial dimension in the direction of motion (propagation). Hence light has forever to go nowhere - producing light's effectively "infinite" velocity, and more to our point, the "non-local" and perfectly symmetric spatial distribution of light's energy. It is the destruction of this spatial symmetric energy state when light is converted to intrinsically immobile massive particles that gives rise to the "location" charge of gravity. (See: "A Description of Gravity".)
Along with the non-local distributional symmetry of light's energy, the intrinsic motion of light also establishes ("gauges") the electromagnetic spatial metric and its symmetry, both with respect to spatial-inertial symmetry and the vanishing of the asymmetric time dimension. Furthermore, the intrinsic motion of light serves as the spatial entropy drive of free electromagnetic energy, creating, expanding, and cooling space. (See: "Spatial vs Temporal Entropy".) The dimensions are primordial entropy domains, establishing a firm foundation for energy conservation. Because all these effects - non-local distributional symmetry, spatial metric symmetry, and spatial entropy drive - are gauged by the electromagnetic constant "c", the gravitational response to the loss of light's intrinsic motion also affects these same parameters - establishing an actual spacetime "location" for a center of mass, "warping" the spatial metric around that center, and providing an alternative entropy drive for matter (time).
The active principle of gravity's "location" charge is time. Time identifies a specific location in space for the center of mass (and the center of a gravitational field); time "warps" the spatial metric by its one-way asymmetry; and the intrinsic motion of time becomes the entropy drive of matter - replacing the intrinsic motion of light. Finally, time and gravity induce each other endlessly - a gravitational field is the spatial consequence of the intrinsic motion of time. Time flows into history at the point-like center of mass (where time is at right angles to all three spatial dimensions), dragging space along with it. However, space cannot enter the historical time line, and a metrically equivalent temporal residue is continuously extracted from space by the gravitational collapse and annihilation of space at every center of mass. (See: "The Conversion of Space to Time".)
The multiple gauge roles of "velocity c", especially with respect to light's entropy drive and non-local symmetric energy distribution, are reflected in the multiple conservation roles of the gravitational response to the conversion of light to matter. (See: "The Origin of Matter and Information".) Gravity is always present for any massive particle, because the entropic time dimension must always be present for any massive particle. At low gravitational field strengths (such as on planet earth), we see only gravity's entropic and metric warping role - that is, we experience the one-way time dimension (clock time), and the one-way flow of space as time pulls space along toward the beginning of the historical time line at Earth's center of mass (the spatial flow of "gravity"). But at high gravitational field strengths - such as on our sun - we see, in addition to gravity's entropy conversion and conservation role, the symmetry-keeping role of gravity, converting asymmetric mass back to symmetric light, recreating a symmetric spatial metric and a spatial rather than a temporal entropy drive. (See: "A Description of Gravity".) The process goes to completion in Hawking's "quantum radiance of black holes" - which is why the universe is so keen to produce them.
We know that a symmetry debt has been paid when its charge and associated force vanish. For example, in a matter-antimatter annihilation, all charges and forces associated with the particles also vanish when the particles themselves vanish. The symmetry debts (charges) which impelled the particle pairs to annihilate each other have been paid in full. In the case of gravity, we see this happening on the sun, where the mass of the sun, and hence the gravitational field associated with that mass, are both slowly vanishing. Since light, moving freely in space, produces no gravitational field of its own, we see that the gravitational symmetry debt has been paid for any mass converted to light. This again tells us the true conservation goal of gravitation - when the force vanishes, its specific symmetry debt has been paid. Because earth's gravity is not strong enough to convert mass to light, it remains forever in its entropy conversion mode, simply converting space to time, so the total gravitational field of earth remains constant.
A familiar financial analogy may help clarify the concepts presented in the paragraphs above. On earth, at low field strength, gravity only pays the "entropy-interest" on matter's symmetry debt; at high field strengths, as on the sun, gravity begins to "pay down" the "symmetry-principle" of its debt, converting local asymmetric mass back to its non-local symmetric origin (light). We will see this process go to completion via the "Hawking radiation" of a black hole in Fig. 9. (See: Section II: Introduction to Gravitation; See also: Why Gravity? A Rationale for Gravitation.)