Galileo's Belated Gravity Experiment: The Small Low-Energy Non-Collider. (PDF) Essay submitted to the Gravity Research Foundation 2015 Essay Contest.

Speed of Gravity • Cosmic Everything Chart. (PDF) Not a "paper," but possibly worth many thousands of words.

Gravity Experiment in Waiting. (PDF) Essentially the same in content as an article submitted to Scientia Salon July 2014. Inspired by the book, Farewell to Reality, and article, The Evidence Crisis, to similar effect by Jim Baggott.

Speed of Light and Rates of Clocks in the Space Generation Model of Gravitation, Part 1. (PDF) 2014. Full scale version of Figure 27: Cosmic Everything Chart. (PDF) — Also linked below.

Rethinking Einstein's Rotation Analogy. (PDF) Entered in FQXi 2012 Essay Contest, May 2012. Essay topic question: Which of Our Basic Physical Assumptions Are Wrong?

Maximum Force Derived from Special Relativity, the Equivalence Principle and the Inverse Square Law. Submitted to International Journal of Theoretical Physics in 2009. (PDF)

The Direction of Gravity. (PDF) Published in Astronomical Review, July 2011.

Missing Measurements of Weak-Field Gravity. (PDF) Published in Progress in Physics, January 2011.

Space Generation Model, Cosmic Numbers, & Dark Energy. (PDF)

Strong Field Gravity in the Space Generation Model. (PDF)

Gravity: The Inside Story. (PDF)

Climbing the Depths of Gravity. (PDF)

Interior Solution Gravity Experiment. (PDF)





Gravity and Sociology: How shall we graph our knowledge of gravity: by guesswork or by experiment?

SLENC as "Gravitational Clock": 1975 NASA Technical Memorandum by Larry L. Smalley. Proposal to measure Newton's constant with a satellite version of a Small Low-Energy Non-Collider. (Never carried out, but still quite feasible.)


Cosmic Everything Chart: Mass vs Density of all bodies of matter in the cosmos. Logarithmic scale of mass covers 80 orders of magnitude; logarithmic scale of density covers 70 orders of magnitude.


Updated Cosmic Everything Chart: Includes expression relating the speed of light to Newton's G and other constants; and an expression relating the SPEED of GRAVITY to the same constants except Nuclear Saturation Density, which is replaced by a proposed MAXIMUM matter density.

Accelerometer Photo Gallery (Yes, it really works! Zero when falling; 9.8 at Earth's surface.)


Book Cover (front and back): Tentative design for work in progress.


Clock Rate Comparison: Coefficients and graphs comparing GR and the SGM.

Mr. Natural reflects on Naturalness: Serious funnybone fizzix.


Higgs boson, Frank Wilzcek, and the physics of mass.


Zeroth Commandment: Make fun of puffed up authorities. [Vector Image] [Pixel Image]













In 1632 Galileo proposed a very simple gravity experiment that has not yet been carried out. My primary objective is to generate interest in fulfilling Galileo's proposal, to see to it that his experiment is duly performed.

In three different passages in his Dialogue Concerning the Two Chief World Systems (University of California Press, 1967; pp. 22, 227, 236) Galileo wondered what would happen "if the terrestrial globe were pierced by a hole which passed through its center, [and] a cannon ball [were] dropped through [it]."

It is obviously impossible to drill a hole through Earth, but the purpose of the experiment would be just as well demonstrated using smaller bodies in an orbiting satellite or Earth-based laboratory.

SLENC Aparatus

The biggest, most expensive machine ever built by humans is designed to hurl bits of matter together into collisions of enormous energy. The machine is called the Large Hadron Collider. By contrast, Galileo's experiment involves the small gravitational energies of ordinary bodies of matter, configured so that the smaller one falls radially with respect to the center of the larger one without ever colliding. The idea is to see how two bodies interact due only to gravity, in a completely undisturbed state. The apparatus may thus be called a Small Low-Energy Non-Collider.


As revealed by dozens or hundreds of papers, textbooks and undergraduate physics courses, the result of Galileo's experiment is routinely presumed to be "well known." Curiously, no empirical evidence is ever provided to support this presumption. Therefore, Galileo's experiment is overdue to be carried out, if only to fill the large gap in our empirical knowledge of gravity. The ideals of science dictate that claims of physical knowldege are to be supported by repeatable experiments. (Nullius in verba.) The prediction for the result of Galileo's experiment has not yet been supported even once.

As it turns out, a particular line of inquiry suggests that, when the experiment is finally carried out, the standard prediction will not be supported. The standard prediction is that the smaller body will have a maximum speed as it passes the center and will oscillate back and forth between the hole's extremities forever. There are reasons to suspect that the smaller body will not pass the center even once.


These reasons are collected into a new model of gravity called the Space Generation Model (SGM). To be viable, any new gravity model must demonstrate agreement with the many observations that support the reigning theory of gravity, Einstein's Theory of General Relativity. This is done for the SGM in a few of the papers listed at left, especially Maximum Force, and Speed of Light and Rates of Clocks.

The latter document features extended sections on how the SGM relates to atomic physics and cosmology. The most noteworthy result of this exploration is that it has led to a simple expression that connects Newton's constant G, to the other constants of physics. I. J. R. Aitchison has expressed the desirablility of finding such a connection:

"Could the dimensions of Newton's gravitational constant be explained... by a theory of gravity characterized by a fundamental mass (or length) and a dimensionless strength? Could we then unify all the forces? Something new is needed." ('The Vacuum and Unification,' in The Philosophy of Vacuum. (Clarendon Press, 1991) pp. 185–186.)

In the expression to follow, we have the speed of light, c; the Bohr radius, a_0; and the electron mass, m_e. These constants combine to form the dimensioned part of G (acceleration of volume per mass). The dimensionless strength is a ratio of densities: The mass-equivalent of the cosmic background radiation, rho_mu; and the nuclear saturation density, rho_N. Altogether, we find

Sphere with Hole

Notice that all three desiderata of Aitchison are fulfilled.

To show more comprehensively how G relates to other constants in quantum theory, we add to the above expression, two more:

Sphere with Hole

where h is Planck's constant; alpha is the fine structure constant, m_p is the proton mass, and R_c is the SGM's cosmic radius.

These expressions are measurably at least very nearly true. If this is not just a coincidence, then they represent a big step toward the unification alluded to by Aitchison.

Perception of the cosmic significance of these connections, especially with regard to the role of the fine structure constant, is facilitated by a figure in the Speed of Light and Rates of Clocks essay. Figure 27 from the essay is called a Cosmic Everything Chart because, on logarithmic scales, it represents all massive bodies and their densities in the Universe, including the Universe itself.

Whether the expressions above are physically true or not, whether the cosmological ideas they go with are true or not, can be determined by conducting the experiment that Galileo proposed 384 years ago.