The Map Drawn by a Fitted Pair: Ginzburg and Landau's Functional and the Price of Its Coefficients

In 1950 Ginzburg and Landau gave superconductivity its order parameter: a complex field \psi with a free energy of Landau's analytic form plus a gauge-coupled gradient term. From that functional flow the coherence length, the penetration depth, their ratio \kappa, and the type-I/type-II divide at \kappa = 2^{-1/2} that still organizes the superconducting world. The functional's two coefficients, \alpha(T) and \beta, are phenomenological inputs, and \alpha's sign change at T_c is stipulated to be linear. This paper audits the fitting. On declared tabulated (\xi, \lambda) pairs the bench returns \kappa for five named superconductors (0.031250 to 1.026316 against the divide 0.707107), computes how far each fitted input must move, alone, to flip its material's class (+58.621251\% of \lambda for lead; -31.102416\% for niobium), and returns the coherence length's divergence under the stipulated linear \alpha(T) against a quadratic alternative: the famous exponent 0.500000 is the stipulation's exponent halved. The map is the fitted pair's placement; the exponent is the stipulation read back. Census headline, unchanged: NOT SOLVED / PARTIAL · producing-count 0.

Authors

Publication Details

Journal
Zenodo (CERN European Organization for Nuclear Research)
Published
2026-11-06
DOI
https://doi.org/10.5281/zenodo.24015521
Primary Topic
Physics of Superconductivity and Magnetism
Type
preprint
Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
preprint

The Map Drawn by a Fitted Pair: Ginzburg and Landau's Functional and the Price of Its Coefficients

William Alexander Aldred
Zenodo (CERN European Organization for Nuclear Research)
Physics of Superconductivity and Magnetism
preprint

The Map Drawn by a Fitted Pair: Ginzburg and Landau's Functional and the Price of Its Coefficients

William Alexander Aldred
preprint en

Abstract

In 1950 Ginzburg and Landau gave superconductivity its order parameter: a complex field \psi with a free energy of Landau's analytic form plus a gauge-coupled gradient term. From that functional flow the coherence length, the penetration depth, their ratio \kappa, and the type-I/type-II divide at \kappa = 2^{-1/2} that still organizes the superconducting world. The functional's two coefficients, \alpha(T) and \beta, are phenomenological inputs, and \alpha's sign change at T_c is stipulated to be linear. This paper audits the fitting. On declared tabulated (\xi, \lambda) pairs the bench returns \kappa for five named superconductors (0.031250 to 1.026316 against the divide 0.707107), computes how far each fitted input must move, alone, to flip its material's class (+58.621251\% of \lambda for lead; -31.102416\% for niobium), and returns the coherence length's divergence under the stipulated linear \alpha(T) against a quadratic alternative: the famous exponent 0.500000 is the stipulation's exponent halved. The map is the fitted pair's placement; the exponent is the stipulation read back. Census headline, unchanged: NOT SOLVED / PARTIAL · producing-count 0.

Zenodo (CERN European Organization for Nuclear Research)
Physics of Superconductivity and Magnetism
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.

Laika access coming soon