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Spatial Geometry as a Projection of Action Phase Compatibility

Jonatan P. camargo

Published Mar 17, 2026• 0 citations
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Abstract

This work investigates the structural relationship between accumulated action, dynamic phase, and the geometry of trajectories in spacetime. Starting from the definition of the dynamic phase \[ \phi=\frac{S}{\hbar}, \] we consider the phase compatibility condition between two admissible evolutions, \[ \Delta S = 2\pi n\hbar, \qquad n\in\mathbb Z, \] established in previous works as a criterion of interferential compatibility between dynamical systems. It is shown that this condition cannot be analyzed independently of the geometry of the trajectories, as the accumulated action is a functional of the path in spacetime. In the variational form, \[ S=\int L(x,\dot x,t)\,dt, \] the action depends on the trajectory in the configuration space; in the minimal relativistic realization, \[ S=-mc^2\tau, \] the accumulated phase is proportional to the proper time and, therefore, to the geometry of the worldline; and, in the canonical form, \[ S=\int (p\cdot dx-H\,dt), \] the action simultaneously incorporates spatial and temporal contributions. From these structures, it is demonstrated that the possibility of phase compatibility between two evolutions depends on the compared geometry of their trajectories. In particular, the relevant geometric structure for the interaction between systems can be interpreted as a projection of the phase compatibility of the accumulated action. It is also shown that the canonical form of the action leads, under the assumption of local differentiability of \(S(x,t)\), to the identities \[ p=\nabla S, \qquad H=-\partial_t S, \] which constitute the differential structure of the Hamilton--Jacobi equation, thus establishing a direct connection between the global interferential condition on the action and the local form of variational dynamics. The obtained result does not aim to replace general relativity nor to fully derive classical or quantum dynamics. Its objective is more restricted: to identify the minimal structural relationship between accumulated action, dynamic phase, and the geometry of trajectories, showing that the geometrically relevant structure for the interaction between systems can be interpreted as a projection of the phase compatibility of the action.

DOI
10.5281/zenodo.19058170

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•Feb 16, 2026•0 citations
This work investigates the structural relationship between accumulated action, dynamic phase, and the geometry of trajectories in spacetime. Starting from the definition of the dynamic phase [ \phi=\frac{S}{\hbar}, ] we consider the phase compatibility condition between two admissible evolutions, [ \Delta S = 2\pi n\hbar, \qquad n\in\mathbb Z, ] established in previous works as a criterion of interferential compatibility between dynamical systems. It is shown that this condition cannot be analyzed independently of the geometry of the trajectories, as the accumulated action is a functional of the path in spacetime. In the variational form, [ S=\int L(x,\dot x,t),dt, ] the action depends on the trajectory in the configuration space; in the minimal relativistic realization, [ S=-mc^2\tau, ] the accumulated phase is proportional to the proper time and, therefore, to the geometry of the worldline; and, in the canonical form, [ S=\int (p\cdot dx-H,dt), ] the action simultaneously incorporates spatial and temporal contributions. From these structures, it is demonstrated that the possibility of phase compatibility between two evolutions depends on the compared geometry of their trajectories. In particular, the relevant geometric structure for the interaction between systems can be interpreted as a projection of the phase compatibility of the accumulated action. It is also shown that the canonical form of the action leads, under the assumption of local differentiability of (S(x,t)), to the identities [ p=\nabla S, \qquad H=-\partial_t S, ] which constitute the differential structure of the Hamilton--Jacobi equation, thus establishing a direct connection between the global interferential condition on the action and the local form of variational dynamics. The obtained result does not aim to replace general relativity nor to fully derive classical or quantum dynamics. Its objective is more restricted: to identify the minimal structural relationship between accumulated action, dynamic phase, and the geometry of trajectories, showing that the geometrically relevant structure for the interaction between systems can be interpreted as a projection of the phase compatibility of the action.
The shape of the classical Lagrangian L=T−V L = T - V L=T−V is universally used in analytical mechanics and in the variational formulation of physics. Despite its conceptual centrality, this structure is historically introduced as a working hypothesis, not usually being derived from more fundamental principles. In this work, we present a systematic derivation of this form from a minimal interferential structure based on the action phase. We start from three physical hypotheses widely observed in interferential phenomena: (i) the existence of an accumulative quantity associated with trajectories, identified as action SSS; (ii) the dependence of physical amplitudes on phase factors of the type eiS/ℏe^{iS/\hbar}eiS/ℏ; and (iii) the possibility of parametrizing evolutions by monotonic proper parameters. We initially show that action differences between systems generate isolated episodic coincidences, implying an operational discretization of interferential compatibility events. These events naturally organize into a discrete network of interactions. Under minimal variational hypotheses—global phase invariance, adjacency locality, and flux conservation—we demonstrate that the structural operator associated with the network coincides with the combinatorial Laplacian K=D−A K = D - A K=D−A, where AAA is the adjacency matrix and DDD the degree matrix. The linear dynamics of complex amplitudes on this network, imposing linearity, unitarity, and locality, leads to a unitary generator of the form H=αK+diag(V) H = \alpha K + \mathrm{diag}(V) H=αK+diag(V) \cite{vrev}. In the continuous limit, the network Laplacian converges to the differential operator −∇2-\nabla^2−∇2, recovering the effective Schrödinger equation. The semiclassical decomposition ψ=a eiS/ℏ \psi = a\,e^{iS/\hbar} ψ=aeiS/ℏ leads, to leading order in ℏ\hbarℏ, to the Hamilton-Jacobi equation ∂tS+(∇S)22m+V=0, \partial_t S + \frac{(\nabla S)^2}{2m} + V = 0, ∂t​S+2m(∇S)2​+V=0, from which we identify the effective Hamiltonian H=p22m+V H = \frac{p^2}{2m} + V H=2mp2​+V. Applying the Legendre transform, we then obtain the Lagrangian L=12mx˙2−V, L = \frac{1}{2}m\dot{x}^2 - V, L=21​mx˙2−V, showing that the T−VT-VT−V decomposition emerges as a direct consequence of the phase's interferential structure and the spectral dynamics of the network operator. As a physical test and validation of the formalism, we extend the result to the relativistic regime, identifying the action phase with proper time. We show that the local term of the network generator acts as a modifier of the effective spacetime metric, naturally leading to the isotropic form g00≈1+2Φ/c2g_{00} \approx 1 + 2\Phi/c^2g00​≈1+2Φ/c2. Under the stationary phase condition for null geodesics, we derive the exact gravitational refractive index. This produces the Einstein light deflection angle (4GM/c2b4GM/c^2b4GM/c2b) purely as a consequence of phase curvature, without postulating the General Relativity field equations. The central result of the work is that classical mechanics (L=T−VL=T-VL=T−V) and the geometric structure of gravitation do not need to be assumed as independent postulates, but emerge simultaneously as effective limits of a variational architecture based on phase interference, episodic discretization, and spectral dynamics in networks.
This short note proposes a structural interpretation of relativistic time dilation in terms of the dynamical phase associated with the action. The starting point is the general relation ϕ=Sℏ, \phi=\frac{S}{\hbar}, ϕ=ℏS​, and, in the case of a free massive particle, the minimal relativistic action S=−mc2τ. S=-mc^2\tau. S=−mc2τ. It follows immediately that the dynamical phase is proportional to the proper time, ϕ=−mc2ℏτ=−ωCτ,ωC=mc2ℏ. \phi=-\frac{mc^2}{\hbar}\tau=-\omega_C\tau, \qquad \omega_C=\frac{mc^2}{\hbar}. ϕ=−ℏmc2​τ=−ωC​τ,ωC​=ℏmc2​. Thus, the proper time can be interpreted as a geometric parameterization of the phase of the relativistic action. It is then shown that the time dilation observed in relative reference frames can be read as a modification of the accumulation rate of the dynamical phase when the geometry of the worldline is altered. This work does not intend to fully derive special relativity nor substitute its geometric formulation. Its objective is more restricted: to formally register that the relativistic structure of proper time admits a natural interpretation as the phase dynamics of the action. Finally, it is indicated that the truly new element of the broader program is not only in this reinterpretation, but in the condition ΔS=2πnℏ \Delta S=2\pi n\hbar ΔS=2πnℏ as a structural criterion of interferential compatibility between dynamical systems.
We investigate the minimal conditions under which two independent dynamical evolutions can remain in stable coherent interaction. The starting point is the existence of a scalar accumulative quantity S[γ]S[\gamma]S[γ] associated with each admissible evolution, together with the possibility of ordering this evolution by a monotonic parameter. From these hypotheses, the dynamical phase is introduced through the relation ϕ=Sℏ, \phi=\frac{S}{\hbar}, ϕ=ℏS​, and it is shown that the observable interferential coherence between two evolutions depends exclusively on the phase difference Δϕ(t)=ϕA(t)−ϕB(t). \Delta\phi(t)=\phi_A(t)-\phi_B(t). Δϕ(t)=ϕA​(t)−ϕB​(t). The analysis of the superposition of two complex amplitudes leads to the necessary and sufficient condition for maximum constructive interference, Δϕ=2πn⟺ΔS=2πn ℏ,n∈Z, \Delta\phi=2\pi n \quad\Longleftrightarrow\quad \Delta S=2\pi n\,\hbar, \qquad n\in\mathbb Z, Δϕ=2πn⟺ΔS=2πnℏ,n∈Z, which arises directly from the periodic structure of the phase and is not introduced as an independent postulate. Then, under the regularity hypothesis ΔS∈C1(I)\Delta S\in C^1(I)ΔS∈C1(I), it is demonstrated that non-degenerate zeros of the function fn(t)=ΔS(t)−2πn ℏ f_n(t)=\Delta S(t)-2\pi n\,\hbar fn​(t)=ΔS(t)−2πnℏ are isolated. As a consequence, the central result of the work is established: if the accumulated action difference is not constant in an open interval, then exact phase compatibility between two evolutions cannot persist continuously in that interval. In particular, under the hypothesis of local non-degeneracy, the instants in which ΔS(t)=2πn ℏ \Delta S(t)=2\pi n\,\hbar ΔS(t)=2πnℏ form a discrete set. This result allows formulating the \emph{Phase Compatibility Principle}: stable coherent interaction between dynamical systems requires continuous accumulated phase compatibility. When phase accumulation rates differ, exact compatibility cannot be maintained continuously and occurs only at episodic instants. A minimal relativistic application shows that this structure includes, as a particular case, evolutions whose phases are controlled by proper time, ϕ=−mc2ℏτ, \phi=-\frac{mc^2}{\hbar}\tau, ϕ=−ℏmc2​τ, so that differences between proper time rates induce phase rate divergences and, consequently, episodic compatibilities. The obtained result establishes, therefore, a structural constraint on the coherence between independent evolutions: the spatio-temporal coexistence of two systems does not imply, by itself, dynamical compatibility. The relevant criterion is the compatibility of their accumulated phases throughout the evolution. The present work does not derive lattice operators, Laplacian structures, mass spectra, specific Lagrangian forms, or spacetime ontologies; it only demonstrates the minimal interferential constraint that governs the possibility of continuous coherence between dynamical evolutions.
We present a variational formulation in which the phase is identified as the operational manifestation of the accumulated action, establishing a structural unification between different physical regimes. It is shown that the fundamental phase of any admissible system is given by ϕ=Sℏ, \phi = \frac{S}{\hbar}, ϕ=ℏS​, from which it follows that the frequency — and, therefore, the operational content of time — emerges directly from the rate of action accumulation, ω=S˙ℏ. \omega = \frac{\dot S}{\hbar}. ω=ℏS˙​. The analysis of the relative phase evolution between independent systems leads to the demonstration that interferential coherence is, in general, episodic, being characterized by a discrete set of instants of compatibility. This results in a precise formulation of the physical interaction as Eint=Eesp∩Eϕ, E_{\mathrm{int}} = E_{\mathrm{esp}} \cap E_\phi, Eint​=Eesp​∩Eϕ​, in which the occurrence of observable events is filtered by phase compatibility. It is further shown that massive and massless regimes correspond to different parameterizations of the same phase structure, eliminating the need for distinct ontologies for these cases. The introduction of linear classical operators, such as macroscopic electromagnetic systems, allows us to demonstrate that such operators act exclusively on the observed phase, ϕobs=ϕfund+ϕC, \phi_{\mathrm{obs}} = \phi_{\mathrm{fund}} + \phi_C, ϕobs​=ϕfund​+ϕC​, shifting the synchronization instants without altering the underlying variational dynamics. As a result, a rigorous distinction is established between the structural level and the observational level: the action governs the fundamental dynamics, while the observed phase corresponds to its operational projection under reading transformations. Finally, the possibility of an extended variational framework in which the experimental apparatus is incorporated into a global functional StotS_{\mathrm{tot}}Stot​ is discussed, leaving this construction as a program for future work.
In this work, we apply the Phase Compatibility Principle, established in \cite{04283}, to the problem of the spatial crossing of two dynamical systems with distinct phase rates. The starting point is the existence of an accumulated action S[γ]S[\gamma]S[γ] associated with each admissible evolution and the definition of the dynamical phase by ϕ=Sℏ. \phi=\frac{S}{\hbar}. ϕ=ℏS​. Exact compatibility between two evolutions AAA and BBB is then characterized by the condition Δϕ(t)=2πn⟺ΔS(t)=2πnℏ,n∈Z. \Delta\phi(t)=2\pi n \quad\Longleftrightarrow\quad \Delta S(t)=2\pi n\hbar, \qquad n\in\mathbb Z. Δϕ(t)=2πn⟺ΔS(t)=2πnℏ,n∈Z. Based on this framework, we distinguish two logically independent domains: the geometric domain of spatial coincidence, Eesp={ t:rA(t)=rB(t) }, E_{\mathrm{esp}}=\{\,t:\mathbf r_A(t)=\mathbf r_B(t)\,\}, Eesp​={t:rA​(t)=rB​(t)}, and the interferential domain of phase compatibility, Eϕ={ t:ΔS(t)=2πnℏ, n∈Z }. E_{\phi}=\{\,t:\Delta S(t)=2\pi n\hbar,\ n\in\mathbb Z\,\}. Eϕ​={t:ΔS(t)=2πnℏ, n∈Z}. The coherent interaction set is then defined by Eint=Eesp∩Eϕ. E_{\mathrm{int}}=E_{\mathrm{esp}}\cap E_{\phi}. Eint​=Eesp​∩Eϕ​. Thus, it is shown that spatial coincidence is a necessary, but not sufficient, condition for exact coherent interaction. In the elementary kinematic case of two linear phases, ϕA(t)=ωAt+ϕA0,ϕB(t)=ωBt+ϕB0, \phi_A(t)=\omega_A t+\phi_{A0}, \qquad \phi_B(t)=\omega_B t+\phi_{B0}, ϕA​(t)=ωA​t+ϕA0​,ϕB​(t)=ωB​t+ϕB0​, we obtain Δϕ(t)=(ωA−ωB)t+Δϕ0, \Delta\phi(t)=(\omega_A-\omega_B)t+\Delta\phi_0, Δϕ(t)=(ωA​−ωB​)t+Δϕ0​, so that, for ωA≠ωB\omega_A\neq\omega_BωA​=ωB​, the instants of compatibility are given by tn=2πn−Δϕ0ωA−ωB, t_n=\frac{2\pi n-\Delta\phi_0}{\omega_A-\omega_B}, tn​=ωA​−ωB​2πn−Δϕ0​​, forming a discrete set. Consequently, an arbitrary instant of spatial crossing t0∈Eespt_0\in E_{\mathrm{esp}}t0​∈Eesp​ does not generically belong to EϕE_{\phi}Eϕ​, and therefore does not generically belong to EintE_{\mathrm{int}}Eint​. A minimal relativistic realization is also presented, based on the action S=−mc2τ, S=-mc^2\tau, S=−mc2τ, which yields ϕ=−mc2ℏτ. \phi=-\frac{mc^2}{\hbar}\tau. ϕ=−ℏmc2​τ. For two systems with distinct proper times, the phase difference is Δϕ=mc2ℏ(τB−τA), \Delta\phi=\frac{mc^2}{\hbar}(\tau_B-\tau_A), Δϕ=ℏmc2​(τB​−τA​), and the inequality between the proper time rates implies a difference between phase rates, reestablishing the episodic character of compatibility. Finally, an operational extension of finite resolution is introduced, in which an interferential tolerance δϕ>0\delta\phi>0δϕ>0 defines effective causal windows of width Δtporta=2δϕ∣ωA−ωB∣, \Delta t_{\mathrm{porta}}=\frac{2\delta\phi}{|\omega_A-\omega_B|}, Δtporta​=∣ωA​−ωB​∣2δϕ​, showing that, in the limit of large spectral separation, the coincidence between spatial crossing and effective compatibility becomes progressively rarer. The central result of the article can be synthesized by the implication spatial coincidence⇏coherent interaction. \text{spatial coincidence} \not\Rightarrow \text{coherent interaction}. spatial coincidence⇒coherent interaction. The work does not intend to derive Bose--Einstein statistics, replace quantum electrodynamics, or construct a complete theory of photon--photon scattering. Its result is more restricted and more precise: it establishes, as a physical application of the Phase Compatibility Principle, that exact coherent interaction between two systems requires not only geometric coincidence but also belonging to the phase compatibility set.
The possibility of distinct physical systems remaining dynamically compatible over time is often implicitly assumed in various areas of physics, from interferometric descriptions to clock comparisons and the analysis of composite systems. In this work, we show that such continuous compatibility is not a generic property but encounters a structural limitation that stems directly from the variational formulation of dynamics. Starting from only minimal hypotheses—the existence of an accumulative action, monotonic proper parametrizations, and operational dependence on action differences via factors eiS/ℏe^{iS/\hbar}eiS/ℏ—we demonstrate that dynamically independent systems cannot maintain functional coincidence of their actions over open intervals, except under fine-tuning. Consequently, moments of compatibility form a necessarily discrete set, and any coherent coupling is effective only within a time scale determined by the difference between the rates of action accumulation. The result does not depend on a specific microscopic model, nor on dissipative, statistical, or environmental mechanisms, being consistent with classical mechanics, relativity, and quantum field theory. It is shown, in particular, that effects such as the loss of interferometric visibility associated with time dilation can be understood as physical realizations of a more general constraint: the structural incompatibility between evolutions parameterized by distinct actions. Thus, the so-called ``compatibility window'' does not constitute a new dynamic principle, but an inevitable consequence of the variational architecture common to established physical theories.