How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
A declared rocket check: initial mass , loss rate and relative exhaust speed give and show that fails
A declared-data check of the open-body material accounting: a body of initial mass losing mass at has . With no external force and ejecta of relative speed opposite a fixed unit direction , its velocity from rest is . It satisfies the material balance identities and violates the naive closed-system law ; the example verifies the identities, the thrust and the failure of the naive law on declared model data. It reports no measurement, no engine data and no empirical comparison.
Example
Declared model data. Adopt the open-body material accounting of Adopted impact and open-mass extensions of the force branch: the isolated reciprocal impulse model, the collinear restitution contact law and the open-body material accounting clause (iii) with, on the open interval containing the initial time , set , , and with a fixed unit vector , , and initial velocity . The ejecta therefore leave with the body's velocity reduced by the constant exhaust speed along . Set , the dimensionless numerical time, so . Primes denote differentiation with respect to physical frame time , read in seconds.
Assertions to check. The balance identities hold with the thrust is along , and the naive closed-system law fails: it would force on .
Facts & Assumptions
Given: The declared maps and the vocabulary of Dimensions and SI unit conventions of the non-relativistic classical mechanics framework.
Material accounting and derived law (Adopted impact and open-mass extensions of the force branch: the isolated reciprocal impulse model, the collinear restitution contact law and the open-body material accounting clause (iii), Variable-mass momentum balance: from and to , Consequences of the adopted impact and open-mass models: continuity of total momentum, the smooth-force exclusion, the restitution solution with , and the open-body and rocket laws clause 6): the model requires and , equivalently .
Calculus (The derivative of at a point that is a limit point of , and differentiability on a set, Sums, scalar multiples, products and quotients: , , , and when , The natural logarithm has derivative 1/x and equals the integral from 1 to x of 1/t, The chain rule, in one line from Carathéodory: if is differentiable at and is differentiable at , then is differentiable at with , If is differentiable with integrable then ; and a bounded derivative makes Lipschitz, Intervals of : the nine order-convex forms, nondegeneracy, and length, The Euclidean inner product on ): for real-valued differentiable functions, on , the chain rule and product rule hold, and a curve with zero derivative on an interval is constant.
Verification
Mass identity: on , in . Since , , so the first balance identity and the positive-mass condition hold.
Velocity candidate: define . By [L2] and , , so , with acceleration units , and . The logarithm acts on the positive dimensionless ratio .
Strong form: , while . Thus the derived law holds with thrust along .
Material identities: the product rule gives . Along with step 1.1 this verifies both balance identities of [L1], with every term in this momentum-rate identity having force units.
Failure of the naive law: would make constant and, since and , would force by [L2]. But the computed is nonzero for ; at , . Hence the naive law fails for this open body, as Consequences of the adopted impact and open-mass models: continuity of total momentum, the smooth-force exclusion, the restitution solution with , and the open-body and rocket laws clause 6(b) records.
Tsiolkovsky value: at , , and . The momentum is approximately , whereas the naive law gives zero. These values come from the exact logarithm before rounding; all are declared model computations, with no measurement or empirical inference.
Remarks
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Signs and conventions. The ejecta velocity is expressed in the same inertial frame as , as Adopted impact and open-mass extensions of the force branch: the isolated reciprocal impulse model, the collinear restitution contact law and the open-body material accounting clause (iii) requires; is the exhaust speed relative to the body, and the thrust points along .
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Units. , , , (Dimensions and SI unit conventions of the non-relativistic classical mechanics framework); and both have the dimension of force.
Depends on
Adopted impact and open-mass extensions of the force branch: the isolated reciprocal impulse model, the collinear restitution contact law and the open-body material accounting
Consequences of the adopted impact and open-mass models: continuity of total momentum, the smooth-force exclusion, the restitution solution with , and the open-body and rocket laws
Variable-mass momentum balance: from and to
Dimensions and SI unit conventions of the non-relativistic classical mechanics framework
Intervals of : the nine order-convex forms, nondegeneracy, and length
The derivative of at a point that is a limit point of , and differentiability on a set
Sums, scalar multiples, products and quotients: , , , and when
The natural logarithm has derivative 1/x and equals the integral from 1 to x of 1/t
The chain rule, in one line from Carathéodory: if is differentiable at and is differentiable at , then is differentiable at with
If is differentiable with integrable then ; and a bounded derivative makes Lipschitz
The Euclidean inner product on
Dependency tree · 2 levels
Sources
- J. Peraire and S. Widnall, 16.07 Dynamics (MIT OpenCourseWare, Fall 2008/2009), Lecture L14 'Variable Mass Systems: The Rocket Equation', Eqs. (11)-(15): $m\,\mathrm d\mathbf v/\mathrm dt=\mathbf F+(\mathrm dm/\mathrm dt)\mathbf v_0$ with $\mathbf v_0$ the transferred matter's velocity relative to the body, and the Tsiolkovsky integral
- David Tong, Classical Dynamics (University of Cambridge), §1.2, printed p. 2: the caution that the closed-system form of the momentum balance does not describe an open variable-mass body