N. 3 - 21 aprile 2001 - Giano Bifronte

I. Old World (pp. 13-160)
1. Newtonian Mechanics
2. Applications of Newtonian Mechanics
3. Non-Inertial Frames of Reference
4. Gravitational Paradox
5. Leibniz and Berkeley
6. Mach and Newton's Mechanics
7. Einstein's Theory of Relativity
II. New World (pp. 161-258)
8. Relational Mechanics
9. Applications of Relational Mechanics
10. Beyond Newton
11. History of Relational Mechanics
12. Conclusion
Weber's idea in his electromagnetic theory (1848) was to use a
potential which depends on the distance and the relative velocity (or, to
be more precise, on the rate of change of the distance) of two electric
charges. This results in a force depending explicitly on the second
derivative of the distance between the charges, and which is always
directed along the straight line joining the two charges. Assis's proposal
for the basic force between two particles is to use the same expression,
with charges substituted by masses (and the proportionality constant
suitably adjusted), in the same way as Newton's attraction law can be
obtained (in inverted historical order, of course) from Coulomb's law.
The "basic (or primitive) concepts" of his theory are: "(1) gravitational
mass, (2) electrical charge, (3) distance between material bodies, (4)
time between physical events, and (5) force or interaction between
material bodies" (p. 163); the postulates of the theory are three:
"(A) Force is a vectorial quantity describing the interaction between
material bodies.
(B) The force that a point particle A exerts on a point particle B is
equal and opposite to the force that B exerts on A, and is directed along
the straight line connecting A to B.
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