This manuscript establishes the foundational architecture of two-body and multi-body stability within the Extended Classical Mechanics (ECM) framework. By replacing curvature-dependent interpretations with ECM's mass-exchange formalism, the analysis demonstrates that gravitational and anti-gravitational behaviour arises from the sign and evolution of effective mass \(M^{\text{eff}}\). Sections 1-5 derive stable, unstable, and transitional regions for positive and negative effective-mass domains, constructing a generalizable ECM phase-space for realistic astrophysical and cosmological systems.
In Extended Classical Mechanics (ECM), gravitational balance between two bodies arises not from equality of classical forces but from equality of mass-exchange intensities. The defining condition is:
where \( \Delta M_{M,1} \equiv -M^{\text{app}}_1 = \Delta PE^{\text{ECM}}_1 \) and \( \Delta M_{M,2} \equiv -M^{\text{app}}_2 = \Delta PE^{\text{ECM}}_2 \). This ensures the expression is interpreted strictly in the ECM framework.
Each body possesses an effective mass:
The ECM gravitational field is expressed as
So the balance point between two bodies separated by distance
d satisfies
With the algebraic solution for the equilibrium location:
This formulation emphasizes that ECM balance is a mass-exchange equilibrium, not force equality or spacetime curvature. For foundational definitions of effective and apparent mass, see [Appendix A] and the treatment of negative apparent mass in [Appendix D].
ECM accommodates repulsion when
The balance condition between a positive Meff (attractive) and a negative Meff (repulsive) source reads:
At the interface, the net mass-exchange vanishes:
In ECM this anti-gravity mechanism is described in detail in [Appendix D], and related mass-polarity discussion is in [Appendix 33] and [Appendix 34].
Regions where Meff changes sign produce instability shells defined by:
This surface marks the threshold where ΔMᴍ switches sign and trajectories shift between bound (inward) and expelled (outward) behaviour. A finite transition zone surrounds this boundary where both contributions coexist and small perturbations decide the outcome.
Mathematically, the total gradient may be written as:
Important references on mass redistribution and internal force generation that underpin instability analysis: [Appendix 11], [Appendix 17], and the frequency-radius dynamics relevant for gradient scaling [Appendix 37].
Meff in Multi-Body SystemsEffective mass is time-dependent:
Sources of evolution include:
For N bodies the net mass-exchange gradient acting on body i is:
See discussions of effective acceleration and mediation in multi-body reversible dynamics: [Appendix 12], and variable matter-mass considerations: [Appendix 47]. Frequency-based contributions to mass evolution are addressed in [Appendix 23 - Part-2] and [Appendix 37].
Stability is defined by overlapping effective-mass fields:
Classify space by the sign of the summed ECM field:
Then:
Phase surfaces generalize classical equipotentials but are defined by mass-exchange parity rather than potential energy. The energy-density and partitioning frameworks underpinning these surfaces are in [Appendix 32], [Appendix 33], and [Appendix 34].
Meff (effective mass; gravitationally active), < code>Mapp (apparent mass), ΔMM (mass-exchange), and geff (effective mass-exchange field). No curvature-based language or cosmological constant is used.
This document establishes ECM foundation for gravitational and anti-gravitational stability structures across two-body and multi-body configurations. The ECM mass-exchange paradigm replaces curvature-based interpretations, enabling a unified framework where stability, repulsion, equilibrium, and phase surfaces emerge directly from the behaviour of \(M^{\text{eff}}\). This forms the basis for further cosmological, astrophysical, and quantum-scale ECM extensions.
The following ECM Appendices and Supplements provide the foundational literature for the concepts discussed in Sections 1-5: