On The Cause of Gravity
| Scientific Paper | |
|---|---|
| Title | On The Cause of Gravity |
| Read in full | Link to paper |
| Author(s) | Duncan W Shaw |
| Keywords | gravity, ether, dark matter, aether absorption, aether inflow, mechanical gravity |
| Published | 2009 |
| No. of pages | 24 |
Read the full paper here
Abstract
This paper proposes a physical explanation for the cause of gravity. The proposal is built upon two fundamental postulates: (1) the existence of aether as a sub-atomic substance; and (2) the absorption of aether by atoms. The explanation which the paper offers for the cause of gravity is that the absorption of aether by atoms causes a flow of aether towards the atoms (e.g., the Earth) and the flowing aether exerts momentum upon any matter in its path. The result is gravity. In addition, this paper suggests that the above concept provides an explanation for dark matter, dark energy and other phenomena.
Overview
Duncan Shaw introduces himself in the paper's second paragraph as "a retired Judge of the British Columbia Supreme Court" who came to the subject by reading and by conversation with physicists, and who concluded that "the physical cause of gravity is not known and that this subject is open to the development of new concepts." He is equally frank about method: "The ideas set out below are strictly conceptual." What follows is a qualitative mechanism, offered without equations, for what physically pushes a falling ball toward the ground.
The proposal has exactly two postulates: that aether exists as a sub-atomic substance made of small, flexible "cells", and that atoms absorb it. Absorption creates a continuous inflow toward every aggregation of matter; the momentum carried by that inflow, delivered to atoms it strikes, is gravity. Shaw's declared target is general relativity's silence on mechanism: "In my view, the General Theory of Relativity sets out the geometry of gravity, but it does not describe the underlying physical mechanics of gravity." He quotes Newton's letter to Bentley on the absurdity of action at a distance through a vacuum, and John Wheeler's account of spacetime gripping mass, and then answers Wheeler's questions in his own terms at the paper's close: "Curved spacetime is the flow of aether in space."
The second half applies the same mechanism to a long list of further phenomena — dark matter, dark energy, wave–particle duality, Mercury's perihelion, light bending, lensing, the twin paradox, mass increase in colliders, inertia — and closes with a proposed test and an invitation to comment.
The argument
The case for an aether
Shaw assembles his warrant largely from authority and from a reading of the two-slit experiment. He cites Newton's Opticks, Maxwell's Dynamical Theory of the Electromagnetic Field on "an ethereal medium pervading all bodies", and — at greater length — four modern sources: Frank Wilczek's "Grid" ("Ether is the old concept that comes closest, but it bears the stigma of dead ideas"), Robert Laughlin's remark that "the modern concept of the vacuum of space, confirmed every day by experiment, is a relativistic ether. But we do not call it this because it is taboo", Cahill's quantum-foam inflow, and Stephen Wolfram's network of nodes. He also cites James DeMeo on Dayton Miller, Maurice Allais, and Tom Van Flandern, and quotes Einstein's 1920 Leyden address that "according to the general theory of relativity space is endowed with physical qualities; in this sense, therefore, there exists an ether." On interferometry he notes that opinion is divided and refers the reader to Cahill's re-analysis of the Michelson–Morley and successor experiments. His own reason is candidly stated as intuition: "My own sense of reason tells me that there must be a physical substance which we call aether."
Absorption and inflow
The novel postulate is that atoms are "complex, organized structures" which are "not perpetual motion machines" — parts are dislodged, energy dissipates, and both must be replenished. Shaw's proposal is that aether is the fuel: atoms draw aether cells in and use them to sustain operation, to hold the atom's interior structured, to bond molecules, as raw material for building heavier atoms, and as the medium of electric and magnetic fields. Because aether "acts like a gas and expands to fill the space available", each absorption is refilled from adjacent aether, producing continuous flow inward.
Momentum transfer from that flow to the atoms it strikes — "the contact point is predominantly the nucleus" — is the gravitational force, and Shaw states that the transfer is proportional to atomic mass "in conformity with the principle of equivalence". Acceleration is explained by a funnelling analogy: "Think of a wide river flowing into a narrow canyon", aether drawn from a vast volume into a small one speeding up as it converges. Mutual attraction between two bodies is handled by a shadowing argument: Sun and Earth each deplete the aether in the region between them, so inflow on their far sides exceeds inflow on their facing sides, and "the resulting pressure differential accounts for the Sun and the Earth being in the grip of each other's gravity". A counterbalancing outflow of radiated particles and energy diminishes but does not cancel gravity; the net inward balance is attributed to accretion, "more mass stays than leaves".
Dark matter and dark energy
Both are held to be the same thing seen twice. The unexplained galactic gravity attributed to dark matter is ascribed to the "immense flow of aether being drawn into" the black holes at the hubs of galaxies and clusters. For dark energy Shaw invokes Kashlinsky, Atrio-Barandela, Kocevski and Ebeling's 2008 Astrophysical Journal dark-flow paper, which reported "a surprisingly coherent bulk motion out to at least 300h−1 Mpc" at 600–1000 km/s and attributed it to "pre-inflationary remnants located well outside the present-day horizon". Shaw suggests the source could equally be "one or more enormous black holes", the acceleration being aether flowing toward them. His conclusion is that dark matter and dark energy "are not separate and distinct phenomena; rather, they are simply the gravitational flow of aether drawn into massive sources".
Comparison with Le Sage
Shaw distinguishes his scheme from the Fatio–Le Sage push-gravity tradition. Both are mechanical, but he argues the aether version is preferable on four counts: the engine lies inside the attracting bodies rather than in an external flux of unexplained origin; the aether has independent work to do in atomic structure and electromagnetism; the heat-buildup objection long raised against Le Sage does not arise; and Le Sage's modern form requires gravitons at more than 20 billion times c, which the aether concept does not assert.
Related applications
Light is treated as purely undulatory. The photon evidence — the photoelectric and Compton effects — is reinterpreted as electromagnetic waves activating aether cells already at the destination, giving "the impression of being particles that have travelled all the way from the source". The analogy offered is a ship's wake: "The actual water that strikes the shore is the water that was already there." Mercury's anomalous perihelion advance is ascribed to the planet meeting denser aether near perihelion; light bending at the Sun and gravitational lensing to the motion of the carrying medium; increased mass in collider debris (Shaw quotes Wilczek's LEP figures, 2×10−28 g in against 6×10−24 g out) to absorption of aether cells by particles ploughing through it; and inertia to "a form of bonding of atomic matter to aether". The twin paradox is said to become intelligible because aether supplies "a physical setting against which the concept of speed has meaning", with aether pressure slowing atomic processes and shrinking matter.
On aberration Shaw is unusually candid. He lists the competing treatments (Carlip, Van Flandern, Jefimenko, Heaviside, Poincaré, Cahill, Ghosh), observes that each author finds his own premises consistent with the absence of gravitational aberration, and then writes: "I do not have the mathematics required to calculate whether the gravity concept this paper proposes leads to the same conclusion. Accordingly, I must leave unanswered the question." He proposes one test: observing free fall well outside atmospheres, on the reasoning that the concept "implies that there must be a limit to the speed of matter in freefall", with the resulting figures possibly indicating the strength and direction of local aether flows.
Assessment
The paper's virtues are honesty and economy. Shaw states his qualifications, his method and his limits without inflation; he declines to claim a result he cannot compute; he identifies a genuine explanatory gap — general relativity does describe the geometry of gravitation and does not offer a contact mechanism — and he does so with Newton's own words rather than a caricature. The proposal is also parsimonious in form: two postulates, one mechanism, applied consistently. The move that gives it any advantage over Le Sage is real and well chosen: making the sink an internal appetite of matter rather than an external flux removes the need for an unexplained cosmic source, and Shaw is right that the classic thermal objection to Le Sage does not transfer directly. His account of dark matter and dark energy as one phenomenon rather than two is at least an attempt at unification rather than an addition of free parameters.
But the difficulties are severe, and most of them follow from the paper's own commitments. Nothing in it is quantitative. There is no expression relating aether density, inflow velocity or absorption rate to gravitational acceleration, and therefore no derivation of the inverse-square law, no value of G, and no way to check whether the mechanism produces 9.8 m s−2 at the Earth's surface rather than some other number. The shadowing argument for mutual attraction is asserted rather than worked: a depletion between two bodies would in general give a distance dependence set by the geometry of the flow, and no attempt is made to show it comes out as 1/r2. The funnelling analogy is likewise decorative — a converging incompressible flow speeds up as 1/r2 in area, which is not by itself the acceleration of a test body.
Several claims sit against established measurement. If atoms continuously absorb aether that transfers momentum, they gain mass or energy at a steady rate; the paper offers no accounting for where it goes, and terrestrial mass and orbital periods are known to extraordinary precision (lunar laser ranging constrains any secular change in G/G to below about 10−13 per year). The bonding account of inertia, and the suggestion that aether drag "may well explain the precession of the perihelion of Mercury", is doubly awkward: the same anomaly is explained twice in the paper, once by denser aether near perihelion and once by aether drag on the orbit, and neither is computed against the measured 43 arcseconds per century. The wholesale rejection of the photon conflicts with single-photon experiments that were already routine in 2009 — antibunching in a beam-splitter, which no wave-in-a-medium account reproduces — and with the photoelectric effect's frequency threshold, which Shaw's "already at the destination" reinterpretation does not address. Treating dark energy as attraction toward a mass beyond the horizon does not reproduce what dark energy was introduced to explain: the isotropic, distance-dependent dimming of Type Ia supernovae, which is not directional, whereas a distant attractor necessarily is. Kashlinsky's dark flow is a separate and much-contested claim about bulk peculiar velocity, and using it for dark energy conflates two different observations.
Finally, the aether's job description keeps growing. Over twenty-four pages it becomes fuel, structural scaffolding for the atom, molecular glue, raw material for nucleosynthesis, the medium of electromagnetism, the carrier of light, the seat of inertia, the source of relativistic contraction, and possibly "the prototype of life". A substance that explains everything qualitatively and nothing numerically is not yet a theory, and Shaw — to his credit — says as much in calling the work "strictly conceptual" and inviting comment. Read as an invitation rather than a result, the paper is a clear statement of what a mechanical account of gravitation would have to look like; read as an explanation, it has not yet begun the arithmetic that would let it be tested.