The Dualbind Gravity Model ── Curvature Emergence from Information Placement Density (Koma Theory)

Abstract

This paper presents the Koma Gravity Model — the gravitational branch of Koma Theory — as a structural hypothesis for the problem domain of emergent gravity. In this model, the spatial placement density of quantum information units is expressed as a dimensionless information field $I_K$, which we call the Koma field. Its gradient is incorporated into the action as a scalar field with a Fisher-information-type form. Through the variable transformation $\psi=\sqrt{I_K}$, the Koma information term can be rewritten into a form isomorphic to the standard kinetic term of a real scalar field, and variation of the metric yields the Einstein equation containing the energy-momentum tensor of the Koma field. In an external region that is static, spherically symmetric, weak-field, and satisfies asymptotically flat boundary conditions, assuming $T_{\mu\nu}^{\mathrm{matter}}\approx0$, $V(I_K)\approx0$, and $dV/dI_K\approx0$, one obtains $|\nabla\psi|^2=b^2/r^4$ from $\psi=a+b/r$, with $|\nabla\psi|^2\propto r^{-4}$ when $b\neq0$. However, this relation follows from the Laplace equation under the external approximation adopted in this paper, and is not, by itself, treated as a physical prediction specific to the Koma Gravity Model. Meanwhile, the derivation connecting the energy-momentum tensor of the Koma field to the weak-field metric potential and the circular-orbit velocity has not been completed in this paper, so the galaxy rotation curve given by the current minimal construction is treated as undetermined. Regarding gravitational lensing, an independently reproducible numerical model has not yet been established at this time, and the physical validity remains undetermined. This paper therefore positions the Koma Gravity Model not as a theory that has established the reproduction of dark-matter phenomena, but as an action-level structural hypothesis connecting information placement density and spacetime geometry, and leaves its phenomenological validity to subsequent research through reproducible mathematical models and observational verification. This version corrects the derivation concerning the galaxy rotation curve in v2.02, and places the physical judgment on gravitational lensing effects on HOLD. For the correction history and differences, see the companion document, the Paper A v2.03 Correction Note. Japanese and English versions are included in this record. Note on Version Lineage Version 3.00 in this record family is retained as a Historical Branch Point. The density-geometry lineage originating from that version now continues independently as Koma Density Geometry under Concept DOI 10.5281/zenodo.22047145. Note on Mathematical Formalization This paper is presented as a structural hypothesis. Mathematical formalization and rigorous proof are intentionally left open, and external verification is welcomed. For correspondence: laboratory@dualbind.comLicense: Creative Commons Attribution 4.0 International (CC BY 4.0)