Chapter 5 Metrology: Measuring & Calibrating Oriented Tension (M)


I. Abstract & Scope
This chapter establishes the minimal metrology pipeline for oriented tension: invert optical (polarimetry/scattering) or spectro-imaging data to obtain Q_ij, calibrate T_fil_ij under controlled mechanical loading, measure relaxation and diffusion (tau_relax, D_Q) in frequency/time domains, and finally perform instrument-response deconvolution and uncertainty synthesis. Every data column must carry unit/dim. If time-of-arrival (ToA) methods are used, both forms must be recorded in parallel with explicit gamma(ell) and d ell.

II. Dependencies & References

III. Normative Anchors (added in this chapter)

IV. Body Structure


I. Background & Problem Statement


II. Key Equations & Derivations (S-series)


III. Methods & Flows (M-series)

  1. M80-1 Polarimetry/Scattering → Order-Tensor Inversion
    • Preprocessing: resample in time–frequency/angle domains; audit Unit/Dim.
    • Modeling: choose 𝓜 (Mueller or scattering kernel) with symmetry (tracelessness) and objectivity constraints.
    • Inversion: solve min_{Q_ij} ‖𝓜[Q_ij] − S_pol‖^2_Σ + λ‖∇Q‖^2; output Q_ij and Cov_Q.
    • Checks: Tr(Q)=0, eigenvalue bounds λ∈[−1/3, 2/3], cross-validated residuals.
  2. M80-2 Mechanical Loading → Tension Calibration
    • Specimen & loading: uniaxial/biaxial/shear paths; record u_vec, strain, and boundaries.
    • Observations: force–displacement and/or full-field strain imaging; unit audit in Pa.
    • Calibration: fit Λ_{ijkl} and (if needed) W_orient parameters A,K via S80-3:
      min_{Λ,A,K} L_T + α‖Λ‖^2 + β‖(A,K)‖^2.
    • Outputs: T_fil_ij, posterior for Λ_{ijkl}, and evidence ratios.
  3. M80-3 Frequency/Time-Domain Relaxation Measurements
    • Frequency domain: small-amplitude sinusoidal excitation; measure Q_ij(ω) or T_fil_ij(ω); fit G*(ω) or H_Q(ω) to obtain tau_relax.
    • Time domain: step/pulse relaxation; fit Q_ij(t) = Q_ij^eq + (Q_ij^0 − Q_ij^eq) e^{−t/tau_relax}.
    • Spatial diffusion: fit broadening of a seeded δQ_ij(r,0) to estimate D_Q.
    • Outputs: posteriors and CIs for tau_relax, D_Q.
  4. M80-4 Response Deconvolution & Uncertainty Synthesis
    • Estimate R_inst and noise spectrum S_n.
    • Choose regularization (Tikhonov/Wiener/sparse priors); deconvolve with unit-closure preserved.
    • Error decomposition: statistical noise, systematics (calibration, alignment, drift), model error.
    • Synthesis: propagate Cov_Q, Cov_T to {Λ, A, K, tau_relax, D_Q} via linearization or sampling.

IV. Cross-References within/beyond this Volume


V. Validation, Criteria & Counterexamples

  1. Positive criteria:
    • Inverted Q_ij is traceless with eigenvalues in-range; CV residuals are whitened.
    • T_fil_ij matches loading curves in units/dimensions and symmetry; evidence exceeds that of orientation-free models.
    • tau_relax and D_Q agree across frequency/time domains; no systematic bias after R_inst deconvolution.
  2. Negative criteria:
    • Adjusting only Λ_{ijkl} or removing orientation terms does not worsen fits (orientation mechanism falsified or nonessential).
    • Unit/Dim audit fails, or R_inst deconvolution introduces spurious bands.
    • Q_ij eigenvalues out of bounds, Tr(Q)≠0, or symmetry violations.
  3. Contrasts:
    • {optical-only, mechanical-only, joint} identifiability and evidence comparisons.
    • {Tikhonov, Wiener, sparse} deconvolution impacts on uncertainty.
    • {uniaxial, biaxial, shear} loading-path condition numbers for estimating Λ_{ijkl}.

VI. Deliverables & Figure List

  1. Deliverables:
    • MetrologyCard.json (observation geometry, R_inst, noise, units, covariance).
    • QTensorPosterior.zarr, TensionPosterior.zarr (posteriors & covariances for Q_ij, T_fil_ij).
    • RelaxationReport.md (tau_relax, D_Q, and consistency checks).
    • UnitsAudit.log, EvidenceReport.md.
  2. Figures/Tables (suggested):
    • Tab. 5-1 Observable–physical mappings with unit-closure checklist.
    • Tab. 5-2 Q_ij inversion and eigenvalue-domain checks.
    • Fig. 5-1 Residual spectra/images before vs after deconvolution.
    • Tab. 5-3 Posteriors & sensitivity matrices for {Λ, A, K, tau_relax, D_Q}.
    • Fig. 5-2 Calibration curves for {uniaxial/biaxial/shear} and model-fit overlays.