Finite-$q$ Corrections to the Carnot Capacity Identification

Closes the open problem LC-O3 (Section 7.2 of TempProj) by a precise separation: the quadratic Lorentz-capacity identity $B_n^2 + (F^\tau_n)^2 = 1$ is exact for every $n$ and receives no correction; the parabolic Carnot-Carathéodory identification is corrected by $\Delta_q(n) = 4m^2/q^2$ outside the pre-saturation regime $n \leq (q-1)/2$.

Read the preprint DOI: 10.5281/zenodo.20334072
Current Zenodo release: version 1.1 (2026-10-24). Official title: Finite-$q$ Corrections to the Carnot Capacity Identification.

Overview

The Lorentz-capacity sub-programme studies the temporal residual $F^\tau_n = \sqrt{1 - B_n^2}$ from the bounded Born-Infeld capacity budget of the admissibility cascade on $\mathrm{Heis}_3(\mathbb{Z}/q\mathbb{Z})$. The note N and the temporal residual paper TempProj give, under the hypotheses stated there, the quadratic identity $B_n^2 + (F^\tau_n)^2 = 1$; its reading as time dilation requires in addition the hypothesis [H-cone] of TempProj, which identifies the light-cone speed of a supplied co-metric with the Born–Infeld bound and is not derived.

The open problem LC-O3, stated in Section 7.2 of TempProj, is the status of the quadratic law and of the parabolic Carnot-Carathéodory identification near the finite-$q$ saturation boundary $n \simeq q/2$. The present paper closes this problem by separating two statements that the statement of the problem conflated.

Capacity vs Carnot identification. LC-O3 is a correction to the Carnot approximation, not to the capacity law. The quadratic identity $B_n^2 + (F^\tau_n)^2 = 1$ is unconditional once $B_n$ is the exact finite-$q$ torus load. Only the unfolded parabolic count $B_n^{\mathrm{parab}}$ deviates from the cyclically folded torus count after the saturation boundary.

Main result

Setting $R := (q-1)/2$ and $n = R + m$, the exact torus count of admissibility cascade points at depth $n$ is

$B_n^{\mathrm{torus}} = \dfrac{q(2m+1) + 2R^2 - 2m^2}{q^2}.$

The deviation from the unfolded parabolic Carnot formula $B_n^{\mathrm{parab}} = (2n^2 + 2n + 1)/q^2$ is closed-form:

$\Delta_q(n) := B_n^{\mathrm{parab}} - B_n^{\mathrm{torus}} = \dfrac{4 m^2}{q^2}.$

The quadratic Lorentz-capacity identity holds for every $n$:

$B_n^2 + (F^\tau_n)^2 = 1, \qquad F^\tau_n := \sqrt{1 - B_n^2}.$

In the macroscopic folded regime $n/q \to \alpha > 1/2$, the correction converges to $\Delta_q(n) \to 4(\alpha - 1/2)^2 > 0$ and the parabolic identification is not asymptotically valid. The correction vanishes in the pre-saturation regime ($n \leq R$), where the Carnot identification is exact, and tends to zero in the sublinear boundary layer ($m/q \to 0$), where it is recovered asymptotically.

Key features

Dependencies

References

Jérôme Beau. Finite-$q$ Corrections to the Carnot Capacity Identification. Preprint, 2026. 10.5281/zenodo.20334072

Relation to the Cosmochrony program

LCo3 is one of three papers that address the open problems of the Lorentz Capacity sub-programme, alongside LCo1 (LC-O1, Lorentz transformations and length contraction) and LCIIo1 (LC-O2-O1, capacity-metric bridge). LCo3 closes LC-O3; LC-O1 is closed conditionally on a supplied co-metric and on [H-cone]; LC-O2-O1 is open, LCIIo1 proving that the scalar free-fraction law does not close it.