(Are Space, Time, And Gravity All Just Illusions? - Big Think) Illustration of the four fundamental interactions (gravity, electromagnetism, strong, and weak) and their associated particles. Gravity stands apart, described by General Relativity, while the other forces are described by quantum field theory (Are Space, Time, And Gravity All Just Illusions? - Big Think). This divide has prompted questions about whether gravity might actually emerge from more fundamental ingredients rather than being a separate fundamental force.
Introduction
Gravity is traditionally counted as one of the four fundamental forces of nature, yet it stands out because it resists unification with the others under a single framework (Are Space, Time, And Gravity All Just Illusions? - Big Think). In Einstein’s General Relativity (GR), gravity is not a force mediated by particles in the usual sense, but a manifestation of spacetime curvature caused by mass-energy (). Meanwhile, electromagnetism and the nuclear forces are described by quantum field theories with force-carrying particles (e.g. photons for electromagnetism). This split in our understanding – GR for gravity vs. quantum theory for electromagnetism and others – suggests our knowledge is incomplete (Are Space, Time, And Gravity All Just Illusions? - Big Think). These tensions have led physicists to ask: Could gravity actually be an emergent phenomenon arising from deeper interactions (such as electromagnetic or quantum processes), rather than a truly fundamental interaction? This overview examines that possibility, surveying mainstream physics views alongside speculative theories that attempt to derive gravity from large-scale electromagnetic interactions, quantum fields, or information-theoretic principles. We will discuss whether gravity might “emerge” from other interactions, highlight models proposing gravity as a macroscopic effect of electromagnetic or quantum fields, outline the challenges these ideas face, and note key proponents and publications of such theories.
Gravity in Mainstream Physics: A Fundamental Interaction
In the mainstream view, gravity is treated as a fundamental aspect of nature, distinct from electromagnetism. General Relativity (1915) describes gravity not as a force field in space, but as the geometry of spacetime itself being warped by energy and momentum (). Any form of energy – mass, radiation, pressure, even electromagnetic fields – contributes to gravity by curving spacetime. In Einstein’s equations, electromagnetic field energy is one source term in the stress-energy tensor, meaning strong electromagnetic fields can produce gravitational effects (for example, light bends spacetime slightly). However, gravity in GR remains a separate phenomenon: it universally affects all matter and light, unlike electromagnetism which only acts on charged particles. Gravitation is always attractive (for positive energies), whereas electromagnetic forces can attract or repel. These differences are tied to the distinct quantum properties of their force carriers: the hypothetical graviton is a spin-2 boson (which leads to always-attractive, long-range behavior), in contrast to the spin-1 photon of electromagnetism. In quantum physics, attempts to quantize gravity straightforwardly (making it a quantum field like electromagnetism) run into theoretical difficulties, and so far there is no complete quantum theory of gravity that has been experimentally confirmed. The fact that gravity is described by a geometric theory while other forces are described by quantum fields highlights why unifying gravity with electromagnetism (and the other forces) is challenging (Are Space, Time, And Gravity All Just Illusions? - Big Think). Historically, there have been attempts to link or unify gravity and electromagnetism at a fundamental level – for example, Kaluza–Klein theory in the 1920s added a fifth dimension to Einstein’s equations and found that electromagnetism can be interpreted as geometric effects in that extra dimension. Einstein himself spent later years searching for a unified field theory of gravity and electromagnetism. These efforts treated both gravity and electromagnetism as fundamental fields within a single framework, rather than deriving one from the other. None of these unification attempts has yet succeeded in producing a confirmed theory, but they underscore how gravity’s unique status motivates thinking beyond standard paradigms.
Emergent Gravity: Gravity from Information and Quantum Microphysics
An alternative viewpoint gaining attention is that gravity might not be fundamental at all, but instead emerges from more basic constituents – perhaps from the collective behavior of microscopic degrees of freedom, information, or quantum interactions. In other words, gravity could be a macroscopic effective phenomenon (like pressure or temperature in a gas) arising from underlying physics.
One influential idea along these lines is entropic gravity, proposed by Erik Verlinde in 2010. Verlinde suggested that gravity is an entropic force – a byproduct of the tendency of systems to increase their entropy (disorder) (Entropic gravity - Wikipedia). In this theory, the fabric of spacetime and gravitational attraction emerge from the information content (or quantum entanglement) of fundamental bits of data associated with spacetime. Gravity, in Verlinde’s view, is not a fundamental interaction but an illusory, emergent phenomenon that arises from an underlying statistical tendency of microscopic states to rearrange (Are Space, Time, And Gravity All Just Illusions? - Big Think). In simple terms, when matter is present, it influences the information/entropy of the surrounding space, and what we feel as gravity is the result of the system striving to maximize entropy (Entropic gravity - Wikipedia). This idea builds on earlier insights connecting gravity and thermodynamics – for example, black hole thermodynamics showed that gravity-rich systems have entropy and temperature, hinting at deep connections between gravitational dynamics and information theory. Indeed, Ted Jacobson in 1995 showed that if one assumes thermodynamic relations (the first law of thermodynamics) hold for all local patches of space (with a horizon), one can derive the Einstein field equations of general relativity as an emergent thermodynamic equation of state (Induced gravity - Wikipedia). This remarkable result suggests Einstein’s gravity may emerge from microscopic degrees of freedom, analogous to how elasticity emerges from molecules in a solid. Similarly, physicist Thanu Padmanabhan has explored links between gravity and entropy, and has derived Newton’s law of gravitation by assuming holographic equipartition of degrees of freedom on horizons (treating gravity like an emergent thermodynamic phenomenon) (Induced gravity - Wikipedia).
Another perspective comes from quantum information and entanglement. Research in the context of the holographic principle and string theory (e.g. the AdS/CFT correspondence) suggests that spacetime geometry itself could be an emergent construct arising from quantum entanglement in a lower-dimensional system. Mark Van Raamsdonk and others have argued that spacetime is essentially “built” from entanglement – if one cuts or reduces entanglement in a quantum state, the corresponding geometric space falls apart (Induced gravity - Wikipedia). In such scenarios, gravity (as the dynamics of spacetime geometry) is not fundamental, but a large-scale effect of underlying quantum interactions. This idea is supported by toy models: for instance, networks of entangled qubits can display behavior analogous to gravitational curvature. In the holographic emergent gravity picture, the entirety of a volume of space with gravity can be equivalent to a quantum field theory without gravity on its boundary; the gravity and spacetime “emerge” from the quantum theory via a duality.
Yet another line of reasoning comes from induced gravity, originally proposed by Soviet physicist Andrei Sakharov in 1967. Sakharov observed that many features of general relativity might naturally arise if spacetime were populated by quantum fields whose vacuum fluctuations can induce curvature. In his proposal, one starts with a baseline of flat spacetime with no fundamental gravity at all, and then introduces standard quantum fields (like those of particle physics). He found that quantum fluctuations at one-loop order generate terms in the effective action that look exactly like Einstein’s gravitational action (the Einstein-Hilbert term) (Induced gravity - Wikipedia). In other words, general relativity arises as an emergent property of matter fields and is not put in by hand (Induced gravity - Wikipedia). This induced gravity approach is analogous to how, in condensed matter physics, elasticity or fluid dynamics emerge from underlying atomic physics. Sakharov’s idea treats gravity as a kind of residual effect of quantum field interactions, essentially an emergent elasticity of spacetime caused by the vacuum energy of those fields. (A challenge here is that naive calculations predict a huge “emergent” cosmological constant – essentially an enormous gravitational effect of the vacuum – that is not observed (Induced gravity - Wikipedia).) Later work in emergent gravity has expanded on Sakharov’s insight. For example, some approaches consider spacetime as a kind of condensate or quantum fluid, where gravitons might be collective excitations (much like phonons in a solid). Others, like the “quantum graphity” model by Konopka, Markopoulou, and Smolin, imagine a network of discrete elements that at high temperature is amorphous, but as it cools, it crystallizes into an emergent spacetime with gravity (Induced gravity - Wikipedia). These are highly speculative but illustrate the range of ideas. Notably, many of these approaches draw analogies from condensed matter: just as crystal defects can mimic curvature and torsion in an elastic medium (Induced gravity - Wikipedia), perhaps the microstructure of spacetime yields the phenomenon of gravity in a similar way.
It’s important to note that while emergent gravity ideas are intriguing and have inspired much research, they remain unproven and somewhat controversial. Verlinde’s entropic gravity, for instance, sparked debate and a number of experiments to test its predictions (Entropic gravity - Wikipedia). The idea that Newtonian gravity could be explained entropically led to tests at short scales and in astrophysical settings. So far, GR (with dark matter) still fits observations better in most cases, but the exploration continues. The mainstream physics community views these ideas with cautious interest: they offer novel ways to think about gravity and have had partial successes (e.g. reproducing Newton’s laws or certain thermodynamic relations), but a full derivation of Einstein’s general relativity or a complete replacement for dark matter using emergent principles is still lacking. Nevertheless, key milestones – Jacobson’s thermodynamic derivation of Einstein’s equations (Induced gravity - Wikipedia), the holographic AdS/CFT duality giving emergent spacetime (Induced gravity - Wikipedia), and Verlinde’s ongoing work – keep the question open: maybe gravity could emerge from deeper laws of physics or information.
Electromagnetism and Gravity: Emergent Connections and Models
A specific variant of the emergent gravity idea is the proposition that gravity might arise from electromagnetic interactions or related quantum fields – essentially, that at a fundamental level, electromagnetic forces (or fields of a certain kind) generate the effects we attribute to gravity. This notion goes beyond the acknowledged fact that electromagnetic energy contributes to gravity (as mass-energy in GR); it asks if gravity itself is a byproduct or residual effect of electromagnetism on large scales.
One line of thought considers whether the gravitational attraction between neutral bulk matter might actually stem from electromagnetic forces when averaged over many particles. Since matter is composed of charged constituents (protons and electrons), one could imagine that subtle imbalances, fluctuations, or van der Waals-like residual forces between those charges could yield a net always-attractive force akin to gravity. In the early 20th century, some physicists speculated that gravity could be a residual force (in the way the strong nuclear force is residual between neutral atoms as the van der Waals force). However, straightforward calculations show that simple electromagnetic attractions in neutral matter are far too small and short-range to explain gravity’s observed strength and 1/r² behavior. So this idea did not become part of the mainstream model.
More modern approaches along these lines involve the quantum electromagnetic vacuum. Physicists Bernard Haisch, Alfonso Rueda, and Harold Puthoff in the 1990s put forward a radical proposal: inertia and gravity might originate in interactions between matter and the vacuum electromagnetic field (the zero-point fluctuations of the quantum vacuum). They argued that an accelerating object feels resistance (inertia) because it is interacting with the sea of electromagnetic vacuum fluctuations – essentially, the zero-point field exerts a drag that looks like inertial mass (emqg99) (emqg99). Extending this, they suggested that gravitational attraction could also be an emergent effect involving the vacuum field. In a 1994 Physical Review paper and subsequent works, they showed that if one assumes the equivalence principle (inertial mass = gravitational mass), then the same electromagnetic vacuum mechanism that gives inertia could also yield weight (gravitation) in a uniform acceleration (gravity) context (emqg99) (emqg99). In a 1997 paper, Haisch et al. wrote that “the ZPF may play an even more significant role as the source of inertia and gravitation of matter.” (Physics of the zero-point field: implications for inertia, gravitation and mass | Speculations in Science and Technology ). In this speculative model, what we perceive as gravitational mass arises partly from the interaction of charged particles with the ambient electromagnetic field of the vacuum. They even predicted a possible very small violation of exact equivalence between inertial and gravitational mass in certain conditions (due to a contribution of genuine gravitational interaction on top of the vacuum EM effect) (emqg99). This approach is highly nonstandard and has been met with skepticism; for example, some analyses argued that the proposed vacuum forces would cancel out or be unobservable. Nonetheless, it represents a serious attempt to tie gravity’s origin to electromagnetism at the quantum level.
There are also attempts to directly unify or connect the fields of electromagnetism and gravity so that one might be viewed as emerging from the other. We already mentioned Kaluza-Klein theory, which in a sense makes electromagnetism a facet of geometry akin to gravity (in 5-dimensional spacetime). More recent theoretical discussions sometimes revisit the idea of “gravity as an electromagnetic effect” (OSF Preprints | Gravity as an Emergent Electromagnetic Effect). For instance, some researchers have explored equations in which a changing electromagnetic energy density could effectively mimic the effects of curvature. A 2024 study of the Gertsenshtein effect is noteworthy in this context: originally proposed by Mikhail Gertsenshtein in 1962, this effect involves the conversion of electromagnetic waves into gravitational waves (and vice versa) in the presence of a strong magnetic field (). It’s a phenomenon allowed by general relativity: essentially, a photonic wave can generate a ripple of spacetime (gravitational wave) if it passes through a region with a powerful static magnetic field. This effect demonstrates a direct coupling between electromagnetism and gravity within GR itself – a bridge between the two interactions (). While the Gertsenshtein effect doesn’t imply gravity is “just electromagnetism,” it does illustrate that under extreme conditions electromagnetic processes can produce gravitational phenomena. In the words of a recent analysis, in the context of this effect “gravity and light… are different manifestations of the same fundamental essence of the universe” ().
Some speculative frameworks go further, postulating that our observed 1/r² gravitational force is an emergent, long-wavelength result of underlying electromagnetic field interactions. For example, one proposal on the research preprint server suggests “gravity emerges from gradients in electromagnetic energy density, where the cumulative effects of kinetic fluctuations within charged matter shape the observed curvature of spacetime.” (OSF Preprints | Gravity as an Emergent Electromagnetic Effect). In plainer terms, this means if charges in matter are constantly jostling (even in neutral matter, charges move internally), their collective influence on the electromagnetic field might produce an average curvature (gravity) at large scales. These ideas often envision a sort of polarizable vacuum or an ether-like medium where electromagnetism and gravity coexist, and gravity arises when electromagnetic field energy varies through space. While intriguing, such models have yet to provide a robust quantitative replacement for Einstein’s equations, nor have they been experimentally verified.
It’s worth noting that electromagnetism-based alternative gravity ideas sometimes surface in fringe science as well. For instance, the so-called “Electric Universe” hypothesis (outside mainstream science) claims that electromagnetic forces, not gravity, dominate the large-scale structure of the cosmos. Proponents argue that galactic rotation curves, usually explained by dark matter’s gravity, could be due to vast electric currents or magnetic fields. However, these claims are not supported by detailed observations – e.g. gravitational lensing and cosmic microwave background data strongly support gravity-based explanations. Nevertheless, the very existence of such ideas underscores the allure of explaining gravity via the better-understood electromagnetic force. Mainstream physics requires any EM-based gravity model to match the extraordinary success of GR: from the orbits of planets and bending of light to gravitational waves. So far, no electromagnetic-emergent theory has met that standard.
Finally, there have been experimental searches for couplings between electromagnetism and gravity. Attempts to detect changes in weight under influence of electromagnetic fields (so-called “gravitoelectromagnetic” experiments) have been largely negative. Famously, in the 1990s Russian researcher Eugene Podkletnov claimed that a spinning superconducting disc could partially shield gravity, suggesting an EM effect on gravity. This result has never been reliably replicated. Other experiments by Martin Tajmar and colleagues reported tiny anomalies in accelerations around rotating superconductor rings (interpreted as maybe a gravitomagnetic effect), but those too remain unconfirmed. If gravity truly emerges from electromagnetism, we might expect some nontrivial interaction in such settings – but to date, none has been clearly observed.
Challenges and Criticisms of Emergent Gravity Theories
The idea of gravity emerging from other physics faces significant theoretical and empirical challenges. One general theoretical hurdle is posed by the Weinberg–Witten theorem in quantum field theory, which (roughly speaking) prohibits obtaining a massless spin-2 field (like the graviton of GR) as a low-energy composite of lower-spin fields under certain reasonable assumptions. This theorem has been used to argue that simple models where gravity emerges from, say, combining two spin-1 fields (like photons) are impossible (Induced gravity - Wikipedia). In Sakharov-style induced gravity, the emergent graviton mode from quantum fluctuations might be forbidden by Weinberg–Witten if the underlying field theory is too conventional. There are ways around the theorem’s conditions (for example, if spacetime itself and Lorentz symmetry also emerge or if the system has strong gauge interactions), but it highlights that you can’t just magic gravity out of standard quantum fields without adding new ingredients (Induced gravity - Wikipedia). Some induced-gravity models therefore require extra features (e.g. emergent spacetime dimensions, as in holographic scenarios) to be viable (Induced gravity - Wikipedia).
Another challenge is empirical: any emergent theory must replicate the precise successes of GR (and Newtonian gravity) across scales, and often this is hard. For example, Verlinde’s entropic gravity in its simplest form deviates from Newton’s inverse-square law at very low accelerations (simulating a Modified Newtonian Dynamics behavior) to account for galaxy rotation curves (Entropic gravity - Wikipedia). While it was interesting that an emergent approach could naturally produce MOND-like behavior, studies of certain galaxies (like dwarf satellites) indicate that the simple version of Verlinde’s emergent gravity doesn’t fit all data as well as dark matter models (Verlinde's emergent gravity versus MOND and the case of dwarf ...) (Are Space, Time, And Gravity All Just Illusions? - Big Think). More generally, cosmology is a testing ground: any alternative gravity must explain the expansion history of the universe, the cosmic microwave background, structure formation, etc. So far, dark matter + GR and dark energy (Lambda) provide a very good fit. Emergent gravity alternatives often struggle to get the right amount of gravitational clustering at all scales (Are Space, Time, And Gravity All Just Illusions? - Big Think).
For EM-based emergent models, a major puzzle is: why would the gravity we feel be so weak compared to electromagnetic forces? In reality, two protons repel each other electromagnetically 10^36 times more strongly than they attract gravitationally. If gravity were a side-effect of electromagnetism, one would need a mechanism for almost perfect cancellation of electromagnetic forces (since matter is neutral) leaving a tiny net force. Such fine cancellations or tiny residuals are hard to naturalize. Moreover, gravity affects neutral particles (like neutrons, or photons which carry no charge) just the same as charged particles – a hallmark of gravity’s universality. Any model deriving gravity from electromagnetism must explain this universal behavior. Typically they invoke the idea that even neutral objects interact with the EM vacuum or have transient polarization, but demonstrating this yields Einstein’s precise equivalence principle and 1/r² law is nontrivial. So far no EM-emergent theory has produced a rigorous derivation of (say) the Schwarzschild metric of a mass or the binary pulsar orbital decay (both classic tests of GR). Also, if gravity had an electromagnetic origin, one might expect some frequency dispersion in gravitational effects (since electromagnetic interactions could in principle depend on frequency of fluctuations), but observed gravitational waves propagate undispersed (as GR predicts). This puts constraints on any theory trying to link them too closely.
Additionally, emergent gravity ideas often predict new phenomena that have not been observed. For instance, the Haisch–Rueda–Puthoff vacuum-based theory implied a slight violation of the equivalence principle in strong fields (they named an “Ostoma-Trushyk effect” of different fall rates for different masses) (emqg99) – but high-precision torsion balance experiments on Earth and lunar laser ranging tests have confirmed equivalence to extremely high precision (no such deviation detected). Entropic gravity might imply a connection between gravity and entropy changes that could be tested in laboratory cold-atom experiments or small-scale gravity measurements; so far, no deviation from Newtonian expectations has turned up in those regimes either.
Mathematically, formulating emergent gravity is complex. For entropic or holographic approaches, one challenge is identifying the true microscopic degrees of freedom and interactions that produce gravity. We have intriguing analogies (e.g. the thermodynamic analogy, or AdS/CFT duality where a specific quantum field theory produces a specific gravity theory in one lower dimension), but when it comes to our universe, we don’t yet know the microstructure of spacetime (if any) that would give rise to Einstein’s equations exactly. There is also the issue of recovering full local Lorentz invariance and continuous spacetime from something discrete or lower-dimensional – not guaranteed and potentially leading to observable Lorentz-violation (which we don’t see). Some emergent models have to fine-tune to avoid giving spacetime a preferred frame or discreteness that would show up as an experimental signal (like energy-dependent speed of light, which is strongly constrained by gamma-ray observations).
In short, while the idea that gravity is emergent is compelling and in some cases elegant, each realization of that idea faces scrutiny on many fronts. To date, general relativity – treating gravity as fundamental – remains the more parsimonious explanation that fits the data, and electromagnetism-based explanations of gravity have not been able to reproduce the precise and varied experimental tests that GR has passed. That said, research into emergent gravity continues, as it may ultimately lead to a deeper understanding of spacetime and help bridge the gap between GR and quantum physics.
Key Proponents and Notable Work
The exploration of emergent gravity spans decades and has involved a number of prominent thinkers, both in mainstream physics and on the speculative fringe. A few notable figures and works include:
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Andrei Sakharov (1967) – Often credited with the first formal proposal of induced gravity, Sakharov’s work suggested that gravity could emerge as a mean-field effect of quantum fields, analogous to elasticity emerging in a medium (Induced gravity - Wikipedia). His idea introduced the paradigm of deriving Einstein’s equations from quantum vacuum effects rather than positing gravity a priori. This paper laid groundwork for many later “emergent spacetime” concepts.
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Jacob Bekenstein & Stephen Hawking (1970s) – Their discovery that black holes have entropy and a temperature (Hawking radiation) revealed a deep connection between gravity, thermodynamics, and quantum theory. This wasn’t an emergent gravity theory per se, but it hinted that gravity might have an underlying statistical interpretation, inspiring later work (Jacobson, Verlinde, etc.) that treats gravity as emergent from entropy/information.
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Ted Jacobson (1995) – In a seminal paper (Phys. Rev. Lett. 75, 1260), Jacobson showed that if one accepts the entropy-area relationship of black holes and the fundamental thermodynamic relation $\delta Q = T dS$ (heat = temperature times entropy change) for local Rindler horizons, one can derive the Einstein field equations. This result strongly suggests that “the Einstein field equations are an equation of state” for whatever microscopic degrees of freedom constitute spacetime (Induced gravity - Wikipedia). Jacobson’s work is a cornerstone of the emergent gravity program in the mainstream literature.
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Erik Verlinde (2010, 2016) – Verlinde’s papers on entropic gravity (2010) and later on emergent gravity and dark energy (2016) gained widespread attention. In 2010 he derived Newton’s law of gravitation by considering the entropy associated with information on holographic screens, concluding that gravity is an entropic force, not fundamental (Entropic gravity - Wikipedia) (Are Space, Time, And Gravity All Just Illusions? - Big Think). In 2016 he expanded this to a relativistic model aiming to account for the observed phenomena usually attributed to dark matter, by emergent gravitational effects. Verlinde’s ideas have been highly debated; they stimulated many tests and analyses, and while not confirmed, they keep the dialogue on emergent gravity alive in the context of astrophysics.
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Thanu Padmanabhan (2000s) – Padmanabhan has written extensively about gravity’s thermodynamic aspects. He demonstrated that Einstein’s field equations can be interpreted as a thermodynamic identity and derived Newtonian gravity by counting degrees of freedom on horizons (an approach similar in spirit to Verlinde’s) (Induced gravity - Wikipedia). His reviews often state “gravity is the thermodynamics of spacetime”, encapsulating the emergent viewpoint.
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Juan Maldacena, Mark Van Raamsdonk, et al. (2010s) – Maldacena’s discovery of the AdS/CFT correspondence (1997) provided a concrete example where a gravity theory is dual to a non-gravitational theory, suggesting gravity can emerge from quantum field dynamics. Building on that, Van Raamsdonk in 2010 explicitly argued (using AdS/CFT) that increasing entanglement between parts of a system literally draws space together, while decreasing entanglement causes space to tear apart, implying “spacetime is built from quantum entanglement” (Induced gravity - Wikipedia). Their work doesn’t directly give a usable emergent gravity theory for our universe (since AdS/CFT involves a specific exotic spacetime), but it’s a strong proof of concept for emergent spacetime in principle.
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S. Steven Gubser, F. Dowker, Fotini Markopoulou, Lee Smolin, and others – Many others have contributed ideas to emergent gravity. Gubser and others have looked at graphene and condensates as analogues for emergent space. Markopoulou and Smolin’s “quantum graphity” (2007) is an example of a toy model where space emerges from discrete bits (Induced gravity - Wikipedia). These are steps toward understanding how a smooth spacetime with gravity could arise from something discrete or network-like.
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Haisch, Rueda, Puthoff (1994–1998) – These researchers are notable for pursuing the idea that electromagnetic zero-point fields cause inertia and gravity. In Phys. Rev. A 49, 678 (1994) they proposed “inertia as a zero-point-field Lorentz force”, and in Speculations in Science and Technology (1997) they argued the same vacuum EM fields could be the “source of inertia and gravitation of matter” (Physics of the zero-point field: implications for inertia, gravitation and mass | Speculations in Science and Technology ). While their papers are outside the mainstream canon and have been met with criticism, they remain a touchpoint in discussions of electromagnetic-origin gravity theories.
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Historical figures – It’s interesting that even in centuries past, thinkers toyed with emergent-like ideas for gravity. Nicolas Fatio de Duillier (1690) and Georges-Louis Le Sage (18th century) proposed that gravity is caused by tiny invisible particles or waves bombarding objects from all sides – normally balanced, but two bodies shadow each other slightly, leading to a net push together. This “Le Sage’s gravity” was a mechanical ether theory producing an emergent force (gravity) from a sea of more fundamental entities. It ultimately fell out of favor (it has severe problems with losses and heating), but it was arguably the first attempt to explain gravity as arising from a more fundamental medium. In the early 20th century, Henri Poincaré and others considered whether gravity could be a residual effect of other fields, and Oliver Heaviside formulated a set of “gravito-electromagnetic” equations in 1893, drawing an analogy between Newton’s law and Coulomb’s law plus adding a magnetic-like gravity component. These did not turn into full theories but show the longstanding temptation to relate gravity and electromagnetism.
In summary, the pursuit of emergent gravity – whether from electromagnetic interactions, quantum information, or other new ingredients – remains a fascinating and actively researched topic. Mainstream physics so far treats gravity as fundamental (with enormous success in describing observations), but the door is open to a deeper theory in which gravity, and even spacetime itself, arises from something more basic. Should a consistent emergent description be found, it would mark a profound shift in our understanding, uniting gravity with quantum physics in a novel way. For now, proposals like Verlinde’s entropic gravity or Sakharov’s induced gravity serve as valuable conceptual experiments, pushing us to question what fundamental really means. As investigations continue – from theoretical studies of entanglement and space to experimental tests of gravity at quantum scales – we edge closer to an answer to whether gravity is truly elemental or an emergent tapestry woven from the threads of electromagnetism, quantum fields, and information.
Sources: General overview of entropic/emergent gravity (Entropic gravity - Wikipedia) (Entropic gravity - Wikipedia) (Are Space, Time, And Gravity All Just Illusions? - Big Think); Sakharov’s induced gravity and related emergent gravity concepts (Induced gravity - Wikipedia) (Induced gravity - Wikipedia) (Induced gravity - Wikipedia); Haisch, Rueda & Puthoff’s zero-point field hypothesis (Physics of the zero-point field: implications for inertia, gravitation and mass | Speculations in Science and Technology ); electromagnetic–gravity coupling via Gertsenshtein effect (); discussions on unification and the status of gravity in modern physics (Are Space, Time, And Gravity All Just Illusions? - Big Think); and various theoretical and experimental insights as cited above.