1822 — The Five-Site Distance-Space Landau Candidate Is Not a Physical d3 Loop Pinch
Defect found
Entries 1786--1790 solved and certified a Landau system in labelled internal distance/Cayley--Menger variables, then pulled its real points into physical three-dimensional loop coordinates. The missing gate was differential: criticality must survive the constrained map
For the proposed pair
physical Landau criticality requires the two loop gradients to be linearly dependent.
Exact physical-gradient audit
At each of the two reflected loop points, compute
and
Exact rational interval propagation over the same isolated algebraic root certifies
on both reflected sheets. Equivalently, the restriction of to the -level tangent plane has strictly positive squared norm on both sheets.
Therefore
The distance-space Landau candidate is not a critical point of the physical (d^3\ell) pullback.
Correct classification
The algebraic Cayley--Menger/distance-space candidate remains valid as an unrestricted coefficient-support calculation. It does not define a physical three-dimensional loop pinch on the frozen current.
This is precisely the type distinction anticipated by Entry 1216: an object of the unrestricted distance continuation need not have an ordinary physical pullback.
Required retractions and retypings
The following physical conclusions are withdrawn:
- Entry 1790's nonzero physical Picard--Lefschetz discontinuity;
- Entry 1791's physical divisor;
- Entry 1792's physical logarithmic extension;
- Entries 1793--1798 insofar as they describe specialization of that physical extension;
- Entries 1801--1807's instantiated Kummer/pole-log coefficient objects;
- Entries 1811--1815's instantiation of a transverse Morse/Gysin family;
- Entries 1817--1818's physical activation and rank-110 physical object;
- Entry 1821's application of threshold stationarity at Gram rank two.
The following narrower statements survive:
- the exact source-denominator and Cayley--Menger algebra;
- Entries 1808--1810's source cancellation, nonzero algebraic residues, and labelled cyclic census, retyped as distance-space/source data;
- Entry 1800's typing warning;
- Entry 1816's frozen-packet gate;
- Entry 1819's standalone coordinate-Jacobian cancellation theorem;
- Entry 1820's universal conditional Rees normal form.
Architectural consequence
This is not a failure of the shared-carrier hypothesis. It is a failure to apply the physical pullback functor before assigning a Betti/Morse coefficient object:
The correction removes the apparent five-site physical threshold evidence but strengthens the requirement that carrier incidence, coefficient support, and physical-chain criticality be tested as separate typed stages.
Next falsifier
Return to the complete source-compatible five-site Landau candidate list and apply the physical gradient-dependence gate before any Hessian, residue, or Picard--Lefschetz calculation. Determine whether any labelled wall pair survives this stricter pullback.
Evidence
- research/benincasa/checkers/five_site_g5_physical_gradient_obstruction.py
- research/benincasa/results/five-site-g5-physical-gradient-obstruction.json
- Entries 1216 and 1788--1821
- allocator claim: seqclaim-662f38ce244c61a6543a7df9