06-ilang-source / 02-what-a-body-presents
02what a body presentsverified
Determines the term through which a body enters the evolution of a field it is coupled to, for bodies at rest, moving, on a clock level and bound in pairs, and which parts are well defined.
# External verification: 02-what-a-body-presents - **Subproject:** 06-ilang-source - **Package:** 02-what-a-body-presents - **Verified version:** v2 - **External round:** 2 of 3 - **Date:** 2026-10-19T10:02:10+02:00 - **Focus points:** none --- VERDICT: minor issues ## Summary The first-order reduced-view equation, remainder estimates, branch-source evaluations, and bound-pair expectation identities are correctly derived. The component decomposition also provides a consistent way to distinguish quantities fixed by the total contract from contract-list conventions. One well-definedness claim is overbroad: additive source differences are invariant under start-independent shifts, but changes of source ratios are not. ## Issues ### I1. Changes of source ratios are not invariant across splits - **Location:** Step 8, Eq. (2.14)(iii), and Result item 13(iii) - **Severity:** minor - **Problem:** “Their changes between two starts” includes the ratios listed in (2.14)(i)–(ii). Although a start-independent shift cancels in \(\Delta S_i\), it does not generally cancel in \(\Delta(S_1/S_2)\). For example, take all \(\mathring\Phi_x=\mathring\Phi\neq0\), and two starts with totals \[ (S_1,S_2)=(q,q),\qquad(-q,q),\qquad q\neq0. \] The difference of their source ratios is \(2\). The allowed move \(W_2=q\mathring\Phi\), compensated in \(C_f\), shifts \(S_2\) to \(2q\) in both starts without changing \(C\). The difference of ratios then becomes \(1\). This counterexample satisfies the identifiability condition in (2.14)(ii) and already applies at \(\lambda=0\). - **Suggested fix:** Restrict the across-split invariance assertion to additive differences such as \(\Delta s_x\) and \(\Delta S_i\). Ratios evaluated in the fixed component split remain functions of \(C\) and the starts, but changes of those ratios are not identical across other splits. If ratios of source differences were intended instead, state that explicitly and require nonzero denominators. ## Focus points None given.