{"id":"hyp-hyper-ribbon-universality","title":"Hyper-Ribbon Universality","subtitle":"Error vectors occupy a low-dimensional manifold (PR 1.05–1.86). Lean-grounded.","category":"conjectures","tags":["hyper-ribbon","sloppy-models"],"source":"articles/docs/conjectures/hyper-ribbon-universality.md","lang":"en","words":199,"readMinutes":1,"toc":[{"depth":2,"text":"Claim","id":"claim"},{"depth":2,"text":"Evidence","id":"evidence"},{"depth":2,"text":"Formal cross-check","id":"formal-cross-check"},{"depth":2,"text":"Why it matters","id":"why-it-matters"},{"depth":2,"text":"Next","id":"next"}],"html":"<h1 id=\"hyper-ribbon-universality\">Hyper-Ribbon Universality</h1><p><strong>Status: Supported · Proven (Lean)</strong></p>\n<h2 id=\"claim\">Claim</h2><p>Prediction-error vectors for elastic constants (<span class=\"katex\"><span class=\"katex-mathml\"><math xmlns=\"http://www.w3.org/1998/Math/MathML\"><semantics><mrow><msub><mi>C</mi><mn>11</mn></msub></mrow><annotation encoding=\"application/x-tex\">C_{11}</annotation></semantics></math></span><span class=\"katex-html\" aria-hidden=\"true\"><span class=\"base\"><span class=\"strut\" style=\"height:0.8333em;vertical-align:-0.15em;\"></span><span class=\"mord\"><span class=\"mord mathnormal\" style=\"margin-right:0.0715em;\">C</span><span class=\"msupsub\"><span class=\"vlist-t vlist-t2\"><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.3011em;\"><span style=\"top:-2.55em;margin-left:-0.0715em;margin-right:0.05em;\"><span class=\"pstrut\" style=\"height:2.7em;\"></span><span class=\"sizing reset-size6 size3 mtight\"><span class=\"mord mtight\"><span class=\"mord mtight\">11</span></span></span></span></span><span class=\"vlist-s\">​</span></span><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.15em;\"><span></span></span></span></span></span></span></span></span></span>, <span class=\"katex\"><span class=\"katex-mathml\"><math xmlns=\"http://www.w3.org/1998/Math/MathML\"><semantics><mrow><msub><mi>C</mi><mn>12</mn></msub></mrow><annotation encoding=\"application/x-tex\">C_{12}</annotation></semantics></math></span><span class=\"katex-html\" aria-hidden=\"true\"><span class=\"base\"><span class=\"strut\" style=\"height:0.8333em;vertical-align:-0.15em;\"></span><span class=\"mord\"><span class=\"mord mathnormal\" style=\"margin-right:0.0715em;\">C</span><span class=\"msupsub\"><span class=\"vlist-t vlist-t2\"><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.3011em;\"><span style=\"top:-2.55em;margin-left:-0.0715em;margin-right:0.05em;\"><span class=\"pstrut\" style=\"height:2.7em;\"></span><span class=\"sizing reset-size6 size3 mtight\"><span class=\"mord mtight\"><span class=\"mord mtight\">12</span></span></span></span></span><span class=\"vlist-s\">​</span></span><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.15em;\"><span></span></span></span></span></span></span></span></span></span>, <span class=\"katex\"><span class=\"katex-mathml\"><math xmlns=\"http://www.w3.org/1998/Math/MathML\"><semantics><mrow><msub><mi>C</mi><mn>44</mn></msub></mrow><annotation encoding=\"application/x-tex\">C_{44}</annotation></semantics></math></span><span class=\"katex-html\" aria-hidden=\"true\"><span class=\"base\"><span class=\"strut\" style=\"height:0.8333em;vertical-align:-0.15em;\"></span><span class=\"mord\"><span class=\"mord mathnormal\" style=\"margin-right:0.0715em;\">C</span><span class=\"msupsub\"><span class=\"vlist-t vlist-t2\"><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.3011em;\"><span style=\"top:-2.55em;margin-left:-0.0715em;margin-right:0.05em;\"><span class=\"pstrut\" style=\"height:2.7em;\"></span><span class=\"sizing reset-size6 size3 mtight\"><span class=\"mord mtight\"><span class=\"mord mtight\">44</span></span></span></span></span><span class=\"vlist-s\">​</span></span><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.15em;\"><span></span></span></span></span></span></span></span></span></span>) across\nhundreds of interatomic potentials do not fill error space. They are compressed onto a\nlow-dimensional <strong>hyper-ribbon</strong> manifold — effective dimensionality far below the\nnominal 3 — consistent with the sloppy-model universality class of Brown &amp; Sethna and\nTranstrum &amp; Sethna.</p>\n<h2 id=\"evidence\">Evidence</h2><ul>\n<li>559 potentials × 15 benchmark metals (8 FCC, 7 BCC), elastic-constant errors from\nOpenKIM, cross-referenced against the NIST Interatomic Potentials Repository.</li>\n<li>Effective (participation-ratio) dimensionality consistently <strong>1.05–1.86 of 3</strong>.</li>\n<li>The structure is not an elastic-constant artifact — see\n<a href=\"#/read/hyp-hyper-ribbon-mlip-transfer\">the de-myopization result</a>: it survives when lattice\nconstant <span class=\"katex\"><span class=\"katex-mathml\"><math xmlns=\"http://www.w3.org/1998/Math/MathML\"><semantics><mrow><msub><mi>a</mi><mn>0</mn></msub></mrow><annotation encoding=\"application/x-tex\">a_0</annotation></semantics></math></span><span class=\"katex-html\" aria-hidden=\"true\"><span class=\"base\"><span class=\"strut\" style=\"height:0.5806em;vertical-align:-0.15em;\"></span><span class=\"mord\"><span class=\"mord mathnormal\">a</span><span class=\"msupsub\"><span class=\"vlist-t vlist-t2\"><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.3011em;\"><span style=\"top:-2.55em;margin-left:0em;margin-right:0.05em;\"><span class=\"pstrut\" style=\"height:2.7em;\"></span><span class=\"sizing reset-size6 size3 mtight\"><span class=\"mord mtight\">0</span></span></span></span><span class=\"vlist-s\">​</span></span><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.15em;\"><span></span></span></span></span></span></span></span></span></span> is added to the manifold (joint PR 1.05–2.05).</li>\n</ul>\n<h2 id=\"formal-cross-check\">Formal cross-check</h2><p>Lean module <code>Materials/Theory/HyperRibbonEmpirical</code>. The\n<a href=\"#/read/formal-audit\">Formal Audit</a> verdict for this claim:\n<strong>&quot;CLAIM PROVEN — EMPIRICALLY GROUNDED.&quot;</strong> Originally the theorem was only consistent\nwith synthetic data; it is now empirically grounded against the real corpus.</p>\n<h2 id=\"why-it-matters\">Why it matters</h2><p>If error is low-dimensional and structured, it is <em>predictable</em> and <em>correctable</em> —\nwhich is the entire premise of the program. A high-dimensional unstructured error would\nhave killed the thesis.</p>\n<h2 id=\"next\">Next</h2><p>Extend the manifold to four property families (add <span class=\"katex\"><span class=\"katex-mathml\"><math xmlns=\"http://www.w3.org/1998/Math/MathML\"><semantics><mrow><msub><mi>E</mi><mtext>coh</mtext></msub></mrow><annotation encoding=\"application/x-tex\">E_\\text{coh}</annotation></semantics></math></span><span class=\"katex-html\" aria-hidden=\"true\"><span class=\"base\"><span class=\"strut\" style=\"height:0.8333em;vertical-align:-0.15em;\"></span><span class=\"mord\"><span class=\"mord mathnormal\" style=\"margin-right:0.0576em;\">E</span><span class=\"msupsub\"><span class=\"vlist-t vlist-t2\"><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.3361em;\"><span style=\"top:-2.55em;margin-left:-0.0576em;margin-right:0.05em;\"><span class=\"pstrut\" style=\"height:2.7em;\"></span><span class=\"sizing reset-size6 size3 mtight\"><span class=\"mord text mtight\"><span class=\"mord mtight\">coh</span></span></span></span></span><span class=\"vlist-s\">​</span></span><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.15em;\"><span></span></span></span></span></span></span></span></span></span>, <span class=\"katex\"><span class=\"katex-mathml\"><math xmlns=\"http://www.w3.org/1998/Math/MathML\"><semantics><mrow><msub><mi>B</mi><mn>0</mn></msub></mrow><annotation encoding=\"application/x-tex\">B_0</annotation></semantics></math></span><span class=\"katex-html\" aria-hidden=\"true\"><span class=\"base\"><span class=\"strut\" style=\"height:0.8333em;vertical-align:-0.15em;\"></span><span class=\"mord\"><span class=\"mord mathnormal\" style=\"margin-right:0.0502em;\">B</span><span class=\"msupsub\"><span class=\"vlist-t vlist-t2\"><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.3011em;\"><span style=\"top:-2.55em;margin-left:-0.0502em;margin-right:0.05em;\"><span class=\"pstrut\" style=\"height:2.7em;\"></span><span class=\"sizing reset-size6 size3 mtight\"><span class=\"mord mtight\">0</span></span></span></span><span class=\"vlist-s\">​</span></span><span class=\"vlist-r\"><span class=\"vlist\" style=\"height:0.15em;\"><span></span></span></span></span></span></span></span></span></span> via the\nPhase-D compute lane) and re-test that the ribbon survives the wider basis.</p>\n"}