The Correspondence That Was Assumed: Landau's Fermi Liquid, Priced

There is a liquid that is not made of atoms in the ordinary sense but of the excitations of a Fermi sea, and for seventy years it has been the working language of every normal metal and of liquid helium-3. Lev Landau built that language in 1956 from a single correspondence idea: switch the interactions on slowly, and the interacting system's low-lying states stand in one-to-one correspondence with the free Fermi gas's — the quasiparticle. From it flow an effective mass, a specific heat linear in temperature with a computable enhancement, compressibility and susceptibility ratios, first sound, and the prediction of zero sound, a collective mode later found in nature. I credit all of it at full strength in this paper. What I price is the correspondence's provenance, and the provenance of the numbers the machinery runs on. The correspondence is assumed, not proved: nothing in the 1956 paper shows it survives a real interaction, and its failures — a pairing instability in any attractive channel, the Mott transition, one dimension, where the quasiparticle pole dissolves entirely — were found by exception, not predicted from inside. The Landau parameters the theory runs on are per-material fitted inputs, an infinite tower truncated by hand, and its exact relations recombine them without deriving any: on my bench the effective-mass ratio runs from 0.033333 to 6.000000 as the single fitted input F₁ˢ runs from −2.90 to +15.00 — the output is the input, divided by three and shifted by one. Grade for this census entry, printed at full size: REASON FOUND / STILL TURNING — explicitly not a kill and not a falsification. The program headline stands unmoved: vacuum catastrophe NOT SOLVED / PARTIAL, producing-count 0.