Gravity: Fundamental Forces and Theories
- Gravity is the universal attractive force that governs interactions between masses and defines the structure of spacetime.
- It is treated through various frameworks including Newtonian mechanics, Einstein’s relativity, and emergent phenomena like thermodynamic and entropic models.
- Gravity underpins both laboratory experiments and astrophysical observations, influencing star formation, cosmic evolution, and the collapse of celestial bodies.
Gravity is the universal attractive interaction that, in the literature surveyed here, is variously treated as Newtonian attraction between masses, as a covariantly defined aspect of spacetime geometry in Einstein’s relativity, as the organizing principle of self-gravitating astrophysical systems, and, in several modern programs, as a thermodynamic, entropic, gauge-theoretic, or pre-geometric emergent phenomenon. Across these treatments, gravity governs the paths of light and matter, the growth of structure, the equilibrium and collapse of stars and compact objects, and a wide range of laboratory and cosmological observables. At the same time, its ontological status remains contested: Newton explicitly rejected the claim that gravity is an innate, essential, and inherent property of matter (Taborda, 2010), while contemporary work explores extensions involving torsion, conformal symmetry, formulations, entropic and horizon-fluid descriptions, and spontaneous symmetry breaking from a pre-geometric phase (Abele et al., 2015, Celada et al., 2016, Bhattacharya et al., 2015, Padmanabhan, 2015, Addazi et al., 2024).
1. Historical and conceptual status
In the historical-philosophical literature centered on Newton’s General Scholium to the second edition of the Principia Mathematica (1713), gravity is not treated by Newton as an essential property of matter. The explicit claim is that Newton “did not believe that gravity was an innate, essential and inherent property of matter,” and that he rejected both the Epicurean thesis that gravity belongs to matter by nature and the scholastic language of occult qualities (Taborda, 2010). In the same discussion, Newton’s position is summarized by the formula “hypotheses non fingo”: he mathematically described the law of universal gravitation while refusing to assign its ultimate cause.
This historical dispute turned on the legitimacy of action at a distance. Leibniz insisted that natural phenomena must be explainable through mechanical causes such as impacts and collisions; absent such a mechanism, gravity appeared to him either as a scholastic occult quality or as miracle. Newton, after earlier attempts involving ether or subtle matter, abandoned such hypotheses in the General Scholium and treated attraction at a distance through vacuum without mediation as “a great absurdity in which no one could believe,” while still refusing to posit an unobserved mechanism (Taborda, 2010). The resulting position is neither straightforward mechanism nor naive essentialism.
The same source presents Newton’s theological framing as integral to this stance. Gravity is described there as requiring an immaterial mediator, associated not with continual direct intervention by God’s potentia absoluta but with the ordained structure of the world, potentia ordinata. In that idiom, gravitation is “a constant energy infused into matter by the Author of all things” [1006.437