The boundary route starts from square-freeness and HUG-WRAP, reaches an exact global three-contact continuum, and then has geometric, degree/return, size-coupling and cap-approximation branches. Its live work is to exclude same-continuum total collision, handle the conditional return alternatives, or obtain global cap compatibility. All-zero return degrees and the distinct scale/chord-parameter regimes remain; no path, unnamed action comparison or complete all-Jordan terminal is supplied.
Route status · Active routePlane topology · configuration geometry · analytic and spectral methods
Inscribed Square Problem
Collaboration betaMust every simple closed curve in the plane pass through the four corners of a square? The current research follows configurations with three corners on the curve and the fourth inside. It reports a connected family across all source separations and a coupling that prevents the second configuration from being smaller than the first. Both sizes can still collapse to zero. Conditional fixed-action, detector and regular-subclass methods remain separate routes, and none currently covers every Jordan curve.

Research problem
Exact mathematical statement
Does every planar Jordan curve contain four distinct vertices of a Euclidean square? Here a Jordan curve is a simple closed curve in the plane. No smoothness, area-zero, genericity, prescribed cyclic source order, or continuous choice of a square is assumed.
The current source leaves this full statement unresolved. Rectangle results at other shapes and results for regular subclasses retain their narrower scope.
Problem infographic
Problem at a glance

Current mathematical picture
Where work on Inscribed Square Problem stands
recorded v52 boundary-continuum, inherited fixed-action and detector frontiers; all-Jordan square existence remains open. Retained v8/v20 objects and inactive history remain explicit, with current source corrections and proof-owner dependencies preserved.
The source reports a lossless lowering measure and explicit shell currents; B0/B1 must still retain controlled-sector mass and accumulate defects into a valid relation, capping/stress transition, or excluded zero model.
Evidence posture · Source-reported route statement · dependencies incompleteReconstruct each smooth spectral, polygon-simplicity and marked-source import at its exact scope; do not treat project strain formulas as external theorems or QSI implementation.
Task status · Ready to work onWe corrected supporting details in the research record. The mathematical claims and their status did not change.
Reader-facing record corrected; mathematics unchangedWork mapped so far
Inscribed Square Problem in numbers
- Argument development
- 4,095 · 80%
- Explored or eliminated routes
- 140 · 3%
- Computational analysis
- 103 · 2%
- Open obligations
- 402 · 8%
- Definitions and setup
- 370 · 7%
How this is measured
This measures retained mathematical investigation, not proximity to a proof. Code, data, logs, repeated text, operational instructions, and generated presentation copy are excluded.
Recommended next task
B45-S
Reconstruct each smooth spectral, polygon-simplicity and marked-source import at its exact scope; do not treat project strain formulas as external theorems or QSI implementation.
Suggested move: Reconstruct each smooth spectral, polygon-simplicity and marked-source import at its exact scope; do not treat project strain formulas as external theorems or QSI implementation.
What would count as progress
- Supply the missing mathematical implication with all stated source hypotheses and retained boundary cases.
- Retain exact evidence for an independent source-fidelity and mathematical review; a model, calculation or branch-only result does not complete the full target.
Argument map and routes
How the current approaches connect
Claims, reductions, open questions, active routes, and narrowed alternatives in one mathematical map.
Visible working map
Research route map
Selected claims, active routes, useful failures, and open questions from the current research map. Arrows appear only for explicitly recorded relationships.
Scroll horizontally to explore the route
Working overview, not proof. The map shows selected recorded relationships; more nodes or edges do not establish correctness or completion.
The boundary route starts from square-freeness and HUG-WRAP, reaches an exact global three-contact continuum, and then has geometric, degree/return, size-coupling and cap-approximation branches. Its live work is to exclude same-continuum total collision, handle the conditional return alternatives, or obtain global cap compatibility. All-zero return degrees and the distinct scale/chord-parameter regimes remain; no path, unnamed action comparison or complete all-Jordan terminal is supplied.
Route status · Active routeThe unmarked detector route requires actual QSI-1 implementation, including coherent natural maps and lifted/localized values, before its first natural image threshold and angular comparison can be used at the displayed finite-constructible scope. Marked QSL-1C/AI-RISK remains a separate unresolved source interface. Positive profile value or endpoint increase does not force positive square-angle slope, and abstract flat models do not settle actual geometric realization or preservation of first detection through switches.
Route status · Active routeThe primitive route uses the displayed common-support ambient budget or finite hull-area variation with selected simple polygons, retaining AI-CPL and AI-RISK; UAP-1 retires the unrestricted universal-budget construction while restricted or square-free-conditional constructions remain. The distinct smooth-response route uses its GL-SM-based formulas only with actual positive bounded-probe or controlled endpoint variation. Critical primitive regularity, unsigned hull accumulation, weak averages or a positive spectral value do not supply those missing inputs or full-target exhaustion.
Route status · Active routeThe charged-family route retains both cofinal exact-critical states and one regular full-tail spine at the source's fixed-action scope. The regular branch keeps physical-cap variation or concentration, both stopping alternatives, complete frontier or coherent corridor, and bounded/unbounded energy and cap-product cases. Its circumcircle terminal needs actual full-tail absolute variation or physical cap uniform integrability on one coherent family. First-hit graph estimates, projected inverse concentration, kinematic examples or tangent concurrence do not supply all missing premises or COV-1.
Route status · Active routeThe retained v20 source reports this route and its unresolved interfaces. Its mathematical statement remains historical recorded evidence; the v52 update does not infer completion from omission. Source-reported live engine with explicit unresolved interfaces; it is not a completed route to the conjecture.
Route status · Active routeThe retained v20 source reports this route and its unresolved interfaces. Its mathematical statement remains historical recorded evidence; the v52 update does not infer completion from omission. Source-reported live engine with explicit unresolved interfaces; it is not a completed route to the conjecture.
Route status · Active routeThe retained v20 source reports this route and its unresolved interfaces. Its mathematical statement remains historical recorded evidence; the v52 update does not infer completion from omission. Source-reported live engine with explicit unresolved interfaces; it is not a completed route to the conjecture.
Route status · Active routeThe retained v20 source reports this route and its unresolved interfaces. Its mathematical statement remains historical recorded evidence; the v52 update does not infer completion from omission. Source-reported live engine with explicit unresolved interfaces; it is not a completed route to the conjecture.
Route status · Active routeThe retained v20 source reports this route and its unresolved interfaces. Its mathematical statement remains historical recorded evidence; the v52 update does not infer completion from omission. Source-reported live engine with explicit unresolved interfaces; it is not a completed route to the conjecture.
Route status · Active routeExplored alternatives
Other routes
The earlier marked-endpoint and vineyard arguments do not close the current source interfaces. Marked QSL-1C / AI-RISK-1 remains a separate qualification, while the alternative unmarked QSI-1 route is still implementation pending. The earlier claim that marked endpoints were not the controlling obstruction does not discharge either interface.
Route status · Useful but insufficientRoute statements and reductions
Statements the next route can inspect and build on
The source labels AN-22--AN-24 and AN-26--AN-29 as proved at their stated scopes and AN-25 as a proved reduction, yielding little-Besov/VMO regularity, deep packet corridors, a network-or-spiral reduction, and compact target-current/multipole data without global closure.
Source-reported route statement · dependencies incompleteThe source retains an odd relative radial class and a conditional carrier-end cocycle, but B2a and RC-21 still require a proper elegant carrier, a base-times-target three-current, cap/slicing identities, anchor transport, and all boundary faces.
Source-reported route statement · dependencies incompleteThe source reports exact finite-dimensional stress data and model exclusions while retaining source packet-chain localization and propagation under source, frame, phase, and scale control as unresolved.
Source-reported route statement · dependencies incompleteThe source reports a lossless lowering measure and explicit shell currents; B0/B1 must still retain controlled-sector mass and accumulate defects into a valid relation, capping/stress transition, or excluded zero model.
Source-reported route statement · dependencies incompleteThe source separates a boundary-continuum tree, an inherited fixed-action tree and an unmarked detector tree. The boundary tree has an unresolved total-collision or return terminal; the fixed-action tree retains the exact-critical and regular full-tail alternatives; the detector tree needs QSI-1 and an additional positive local-slope input. No exhaustion theorem covers every remaining Jordan curve.
Source-reported route statement · dependencies incompleteA route to the full target must provide an actual sufficient endpoint under its displayed premises and cover every remaining Jordan curve. Closing a boundary collision subcase, a single charged leaf, a geometric model, or a conditional detector branch is not the missing exhaustion theorem.
Source-reported route statement · dependencies incompleteThe source keeps two distinct upstream interfaces: an independent reconstruction of marked QSL-1C at AI-RISK-1 scope, and implementation of unmarked QSI-1 in the actual twisted periodic category with lifted endpoint, family-Hom, localization and coherent-gauge conditions. The older unqualified statement that the marked-endpoint problem is not controlling must not erase either live interface.
Source-reported route statement · dependencies incompleteAt the source's accepted-root scope, every sufficiently deep state has a pointwise fixed-action consequence. This does not choose a continuous square, a detector, or an all-scale carrier. RSP-1 preserves cofinal exact-critical charged states as an alternative to a regular charged full-tail spine; neither can be discarded in favor of a convenient branch.
Source-reported route statement · dependencies incompleteThe inherited supplied-family arguments retain hits, no-hits, filler channels, source and action rims, both endpoint channels and every selected face. Normalized convergence does not supply physical cap control, source BV, uniform mass, a full positive-wall family map or a terminal for unbounded normalized lens mass.
Source-reported route statement · dependencies incompleteCIV-1 gives charge collapse only from the stated weighted center/radius variation or physical cap uniform integrability on one full-tail regular spine. Projected inverse concentration, pointwise bounded energy, state-switching examples and tangent models do not supply that premise.
Source-reported route statement · dependencies incompleteUnder the source's square-free Jordan assumption and HUG-WRAP interface, BPG-1 supplies one connected closed configuration set with three actual boundary corners, the missing corner in the interior, the full angle range and retained compact positive-size crossings. It supplies no path, manifold structure, BV or action spine, continuous square selector, or unique endpoint. Rerooting need not preserve the chosen band; balanced compact subsets need not connect the signs.
Source-reported route statement · dependencies incompleteThe source derives strict inradius/radius/hull-area obstructions and a return-degree formula on compact continua. Reverse source order forces a nonzero return degree; positive order can have all degrees zero. Cap hull area and angular advance do not control tangent action or an approximation rate. Return at chord parameter tending to one is terminal only if side length stays nonzero; parameter tending to zero permits narrow return.
Source-reported route statement · dependencies incompleteFor every sufficiently small prescribed eta, BMC-1 uses a compact connected size-floor set through a fixed core to couple a side-eta configuration with another side lambda at least eta whose missing corner lies on the first chord. B4P-1 produces four actual separated boundary points, not the four corners of one square. Both scales can tend to zero; no compatible choice across eta, nonzero final size, or terminal in every ratio/chord-parameter regime is supplied.
Source-reported route statement · dependencies incompleteAGC-1/2 give sufficient bounds at their stated isotopy, length and incremental-budget scope. UAP-1 defeats the unrestricted universal bounded ambient budget using a square-containing zero-area Jordan example whose smooth approximants have unbounded primitive oscillation. Square-free-conditional and explicitly restricted constructions remain open. C0, Hofer, L2 or finite-q Lorentz strain cannot replace the endpoint cost.
Source-reported route statement · dependencies incompleteFinite hull-area or stated mixed variation yields source-reported sufficient results only through the selected simple-polygon and spectral-import hypotheses. The sharp half-Hölder primitive threshold is not a sharp square-existence threshold. Infinite local unsigned hull variation does not supply signed charge, smooth models, primitive failure or actual crossings.
Source-reported route statement · dependencies incompletePositive all-secants endpoint variation or positive response to a bounded smooth Hamiltonian can force a square under the displayed imports and source interfaces. Full-gradient, common-gauge and actual-detection hypotheses remain explicit. Abstract flat models do not establish realization by a Jordan curve; weak averaging can destroy nonlinear single-square moment equality; positive spectral response and bounded strain are additional inputs.
Source-reported route statement · dependencies incompleteMore ways to contribute
Open questions
Additional prepared tasks for exploring this research frontier.
Reconstruct each smooth spectral, polygon-simplicity and marked-source import at its exact scope; do not treat project strain formulas as external theorems or QSI implementation.
Suggested move: Reconstruct each smooth spectral, polygon-simplicity and marked-source import at its exact scope; do not treat project strain formulas as external theorems or QSI implementation.Exclude simultaneous collapse on the same all-scale continuum in every relative-scale and chord-parameter regime; a normalized square does not complete fourth contact.
Suggested move: Exclude simultaneous collapse on the same all-scale continuum in every relative-scale and chord-parameter regime; a normalized square does not complete fourth contact.Retain first detection across switches and prevent collapse without equating grading and action cost.
Suggested move: Retain first detection across switches and prevent collapse without equating grading and action cost.Obtain global compatibility or the required approximation rate, rather than excluding one local cap picture.
Suggested move: Obtain global compatibility or the required approximation rate, rather than excluding one local cap picture.Force variation for the actual product-geometric detector, beyond the axioms defeated by flat models.
Suggested move: Force variation for the actual product-geometric detector, beyond the axioms defeated by flat models.Force positive bounded-probe response or controlled endpoint variation; individual moments and unbounded Hessians are insufficient.
Suggested move: Force positive bounded-probe response or controlled endpoint variation; individual moments and unbounded Hessians are insufficient.Implement all listed QSI conditions in the actual category, rather than substituting an abstract lemma.
Suggested move: Implement all listed QSI conditions in the actual category, rather than substituting an abstract lemma.Construct a positive-wall/pair-space family map with every named source, seam, action-rim, frame and selection face.
Suggested move: Construct a positive-wall/pair-space family map with every named source, seam, action-rim, frame and selection face.Use a nonzero return degree without extracting a path; deal with narrow return and the all-zero-degree positive-order case.
Suggested move: Use a nonzero return degree without extracting a path; deal with narrow return and the all-zero-degree positive-order case.Terminate cofinal exact-critical charged states at their actual scope or construct a coherent family; retain the alternative even without outer safety.
Suggested move: Terminate cofinal exact-critical charged states at their actual scope or construct a coherent family; retain the alternative even without outer safety.Supply full-tail circumcircle variation or physical cap uniform integrability on one charged spine, or contradict its concentration.
Suggested move: Supply full-tail circumcircle variation or physical cap uniform integrability on one charged spine, or contradict its concentration.Use the remaining infinite local hull-variation alternative without converting unsigned accumulation into signed charge or crossings.
Suggested move: Use the remaining infinite local hull-variation alternative without converting unsigned accumulation into signed charge or crossings.Independently reconstruct the marked QSL-1C statement and risk scope.
Suggested move: Independently reconstruct the marked QSL-1C statement and risk scope.Replace the false universal budget task by a square-free-conditional or explicitly restricted construction with the actual stated cost.
Suggested move: Replace the false universal budget task by a square-free-conditional or explicitly restricted construction with the actual stated cost.Bridge actual three-contact continua to four crossings or a terminal model; third contact itself is no longer the missing task.
Suggested move: Bridge actual three-contact continua to four crossings or a terminal model; third contact itself is no longer the missing task.Bound unweighted energy on one contiguous CAS band or terminate concentration; sigma-weighted estimates alone do not suffice.
Suggested move: Bound unweighted energy on one contiguous CAS band or terminate concentration; sigma-weighted estimates alone do not suffice.Extract an actual applicable geometric model or finite certificate from the curve; none follows from embeddedness alone.
Suggested move: Extract an actual applicable geometric model or finite certificate from the curve; none follows from embeddedness alone.Use actual connections, whole matching or closed collar traversal; strand count and a pencil limit do not suffice.
Suggested move: Use actual connections, whole matching or closed collar traversal; strand count and a pencil limit do not suffice.Retain aligned and crossed endpoint channels and distinguish tangent-singular from charged pairs.
Suggested move: Retain aligned and crossed endpoint channels and distinguish tangent-singular from charged pairs.Prove that actual sufficient endpoints cover every remaining Jordan curve; completing one conditional subbranch does not close the target.
Suggested move: Prove that actual sufficient endpoints cover every remaining Jordan curve; completing one conditional subbranch does not close the target.Prove all-Jordan coverage for any independent Floer/rhombus route and any claimed class/action comparison.
Suggested move: Prove all-Jordan coverage for any independent Floer/rhombus route and any claimed class/action comparison.Convert near-singular occupation into oriented geometry with actual lifts, labels and excursions.
Suggested move: Convert near-singular occupation into oriented geometry with actual lifts, labels and excursions.Terminate the same persistent charged gap, including unbounded normalized lens mass, without converting normalized limits into physical control.
Suggested move: Terminate the same persistent charged gap, including unbounded normalized lens mass, without converting normalized limits into physical control.Retain every source boundary of the actual rough missing-vertex incidence, including an indispensable zero-action connector.
Suggested move: Retain every source boundary of the actual rough missing-vertex incidence, including an indispensable zero-action connector.Obtain coherent tangent, germ and sign information on the same gap despite low-speed backtracking.
Suggested move: Obtain coherent tangent, germ and sign information on the same gap despite low-speed backtracking.Recover source, tangent and radial data and selected faces; finite analytic complexity is not uniform mass.
Suggested move: Recover source, tangent and radial data and selected faces; finite analytic complexity is not uniform mass.Sourced mathematical context
The known mathematical landscape
What the literature has established
Selected external milestones in reverse chronological order, with their evidence posture.
PreprintFloer homology and square pegs supplies a representative external result or boundary relevant to the problem; it is not treated here as a proof of the full packet target.[1] PreprintThe rectifiable rectangular peg problem supplies a representative external result or boundary relevant to the problem; it is not treated here as a proof of the full packet target.[2]
Mathematical neighborhood
Related results and reusable starting points
Formalization opportunities
Lean work can make these reusable foundations precise without being presented as a proof of the core problem.
- Formalization targetA formal statement matching the exact public target and all quantifiers.
- Formalization targetFormal libraries for the principal mathematical structures used by the strongest route.
- Formalization targetA checked closing argument for the source-identified open bridge.
Later mathematical changes
What changed after the initial research map
Later recorded revisions that changed the mathematics, without inventing a date or an AI attribution.
Changed the research frontierLater mathematical revision
Changed the research frontierLater mathematical revision
The initial argument structure appears separately. Uploads, model runs, and presentation changes do not count as mathematical updates.
Research-record corrections
What changed in the research record
These notes describe corrections to cited passages, highlighted tasks, or connections between claims. The mathematical claims and their status did not change.
Corrected the research recordCorrection note
Corrected the research recordCorrection note
Corrected the research recordCorrection note
Corrected the research recordCorrection note
Corrected the research recordCorrection note
The initial argument structure appears separately. Uploads, model runs, and presentation changes do not count as mathematical updates.
Detailed research inventory
Claims, milestones, and routes in the current map
This inventory covers all currently cataloged mathematical statements in the research notes.
- equivalence
1 of 23 1 - lemma
16 of 23 16 - negative result
1 of 23 1 - reduction
4 of 23 4 - theorem candidate
1 of 23 1
v52 recorded research frontierThe current frontier is global exclusion of BMC-1/B4P-1 coupled total collision. Third-contact reconstruction is no longer the missing task; an approximate-map path does not yield an exact three-contact path. Both return-degree cases, source orientations and relative-scale alternatives remain, and inherited routes retain their original hypotheses and source risks. The current work reports conditional arguments, imports, scoped obstructions and limited checks without a complete proof or formal certification.81 displayed rows · 9 routes included
- retained route statementSquare-free contradiction formulationintermediate
- retained route statementAN-22--AN-29 quantitative corridor and target-current packetintermediate
- retained route statementv20 implication firewall and retired shortcutsintermediate
- retained route statementRadial/capping carrier and typed-transfer engineintermediate
- retained route statementSource-localized self-stress/model engineintermediate
- retained route statementElegant contour-shell engineintermediate
- Useful failureRepresentation-level, regularity, and calibrated-moment shortcutsreported failure
- Research targetB2a: select a proper oriented elegant carrier or classify every singular continuation obstruction.open
- Research targetRC-21: construct the finite-slab base-times-target three-current, cap/slicing formula, anchor transport, and every boundary face.open
- Research targetB3: convert an isolated later vertex-on-side incidence or endpoint relation into an inscribed boundary square, or into a route already covered by B2b, B4S, or B4T.open
- Research targetB4S: convert hidden/cancellation defects or localized target data into a source-sheet, grid, packet-chain, or stressed-slab theorem.open
- Research targetB0/B1: retain controlled-sector contour-shell mass and accumulate its defects into a valid relation or excluded model.open
- Research targetB4T: classify every compactness failure by a proved transition or escape coordinate.open
- Research targetB6: independently formalize every P* input actually used by a terminal route and audit orientations and compactification faces.open
- retained route statementEvery planar Jordan curve contains a nondegenerate square
- retained route statementParallel boundary, fixed-action and detector routesintermediate
- retained route statementClose every remaining Jordan-curve alternativeintermediate
- retained route statementSeparate unmarked QSI and marked source riskintermediate
- retained route statementFixed action without a chosen square selectorintermediate
- retained route statementStopping deficits and phase costs retain their quantifiersintermediate
- retained route statementRetain source faces, both endpoint channels and physical scaleintermediate
- retained route statementA terminal on one complete regular charged leafintermediate
- retained route statementGeometric subclasses and finite certificate scopeintermediate
- retained route statementRecurrence needs positive size and actual connectionsintermediate
- retained route statementOne connected all-scale three-contact continuumintermediate
- retained route statementSource order, return degree and positive capsintermediate
- retained route statementCoupling removes decreasing size, not total collapseintermediate
- retained route statementLocal countermodels do not realize a square-free Jordan carrierintermediate
- retained route statementThe universal ambient budget is withdrawnintermediate
- retained route statementFinite variation results retain selected polygon and spectral riskintermediate
- retained route statementActual positive response remains an additional premiseintermediate
- Recorded relationshipThe displayed boundary, fixed-action and detector routes support a conditional approach to the all-Jordan endpoint only together with an exhaustion theorem covering every remaining curve. The source explicitly leaves COV-1 and each named terminal open; this edge is a proposed sufficiency relation, not a derivation of the target.supports · reported by source
- Recorded relationshipRetain the earlier all-deep-family premise only inside the inherited fixed-action branch. The v52 frontier keeps full-tail family and formal comparison hypotheses; that retained premise supplies neither the independent boundary-continuum terminal nor an actual detector implementation.supports · reported by source
- Recorded relationshipThe earlier odd relative radial class and conditional carrier-end cocycle remain bounded by their retained predecessor-source carrier, cap/slicing, anchor and full-boundary conditions. The current source material separately defines labelled cap/current boundaries, retains every named face, and refuses to identify its new boundary integers with integrated cap currents or action without a named comparison. This edge records that current limitation; it does not claim that the new continuum constructs the historical carrier or RC-21.supports · reported by source
- Recorded relationshipThe earlier finite-dimensional self-stress data and model exclusions retain their predecessor-source scope. The current source material derives filled-rectangle response and spatial-strain estimates for the displayed smooth spectral setting, with compulsory positive endpoint displacement as an extra hypothesis. These response formulas supply neither the historical source-localized packet-chain propagation nor full-target exhaustion; no equivalence between the two stress notions is asserted.supports · reported by source
- Recorded relationshipThe earlier lossless lowering measure and contour-shell context retain their predecessor-source controlled-sector and defect-accumulation conditions. The current source material has shifted-radius transport estimates and a stopped first-hit graph, but explicitly withholds a full-tail L1 bound and uniform mass and retains hits, no-hits, fillers and restriction faces. This edge does not identify that graph with the historical shell current or infer a terminal transition from the shared notation.supports · reported by source
- Recorded relationshipThe earlier recorded firewall remains retained at its predecessor scope. The current no-revisit registry independently requires the correct mark/action comparisons, actual carriers and jump excursions, both continuation alternatives and endpoint channels, and all current faces and physical cap hypotheses. Its finite identities, normalized limits and one-branch terminals do not close COV-1 or reinstate an earlier rejected implication.supports · reported by source
- Recorded relationshipAt the displayed charged-state scope, the signed-chain action estimate gives turning-cost lower bounds, not a contradiction. The stopping construction starts on one surviving radial square spine with a continuous charged action representative and retains the first critical-or-height alternative. These are conditional continuations of the fixed-action branch; they neither select an arbitrary all-Jordan family nor complete the target.supports · reported by source
- Recorded relationshipThe inherited transport, cap and frontier interfaces start on the displayed CAS-1 sheet or charged spine and retain that family and every boundary face. The stopped two-sheet frontier over a contiguous action interval retains source/seam/action-rim/selection faces; its flat estimate is not a bound on boundary mass or a claim of singular support. These supplied-family statements depend on the fixed-action/stopping construction and do not provide an all-Jordan terminal.supports · reported by source
- Recorded relationshipOn one coherent regular charged family, the circumcircle formulas yield the stated terminal only with full-tail physical cap uniform integrability or absolute weighted center/radius variation. Pointwise bounded energy, cofinal compactness, relabeling or normalized cap convergence do not supply that premise. This is a conditional terminal of the retained charged-family route, not a proof for every Jordan curve.supports · reported by source
- Recorded relationshipOn the source-ordered exact continuum K, the conserved cap indices give the displayed return-degree formula. A nonzero degree permits compact connected-base continuation to an exact return family; reverse order forces such a degree, while positive order may have all degrees zero. A return point is not the missing corner, and the endpoint return is terminal only with positive limiting side. This conditional chain does not identify cap winding with action or construct a path through K.supports · reported by source
- Recorded relationshipThe second missing-corner coupling and the connected size-floor construction yield BMC-1 for every sufficiently small prescribed side on the same all-scale continuum, independently of a nonzero return degree. B4P-1 then supplies four separated actual boundary points. They need not be the corners of one square, and simultaneous physical collapse remains possible; the source supplies neither a compatible path across scales nor a terminal for every relative-size/chord-parameter regime.supports · reported by source
- DerivationThe governing source separates partial or conditional routes from exhaustive target closure. The conjecture would require every displayed premise and every remaining branch to be discharged. This is an informal dependency record, not a verified derivation.proposed
- Research targetB51-C/R51-Copen
- Research targetB51-R/R51-Ropen
- Research targetB51-T/R51-Topen
- Research targetB45-P/R45-Popen
- Research targetB47-E/R47-Eopen
- Research targetB49-C/R49-Copen
- Research targetB49-M/R49-Mopen
- Research targetB45-G/R45-Gopen
- Research targetB47-H/R47-Hopen
- Research targetB45-H/R45-Hopen
- Research targetB45-Sopen
- Research targetB43-Q/R43-Qopen
- Research targetB37-SRC/R37-Eopen
- Research targetB43-A/R43-Aopen
- Research targetB43-D/R43-Dopen
- Research targetR37-G/B37-Gopen
- Research targetB41-V/R41-Vopen
- Research targetB39-Kopen
- Research targetB37-A/R37-Aopen
- Research targetB37-C/R37-Dopen
- Research targetB41-Eopen
- Research targetB37-B/R37-Bopen
- Research targetB37-D/R37-Copen
- Research targetB37-Eopen
- Research targetB37-F/R37-Fopen
- Research targetCOV-1open
- Useful failureRSE-2 / NR-437reported failure
- Useful failureUAP-1 / B45-G/R45-G / AGC-1 / AGC-2reported failure
- Useful failureAFC-1 / MOM-1reported failure
- Active routeRetained v20 route: Two-center analytic corridorThe retained v20 source reports this route and its unresolved interfaces. Its mathematical statement remains historical recorded evidence; the v52 update does not infer completion from omission. Source-reported live engine with explicit unresolved interfaces; it is not a completed route to the conjecture.
- Active routeRetained v20 route: Radial alternating end transferThe retained v20 source reports this route and its unresolved interfaces. Its mathematical statement remains historical recorded evidence; the v52 update does not infer completion from omission. Source-reported live engine with explicit unresolved interfaces; it is not a completed route to the conjecture.
- Active routeRetained v20 route: Two-center self-stress/model routeThe retained v20 source reports this route and its unresolved interfaces. Its mathematical statement remains historical recorded evidence; the v52 update does not infer completion from omission. Source-reported live engine with explicit unresolved interfaces; it is not a completed route to the conjecture.
- Active routeRetained v20 route: Elegant contour-shell routeThe retained v20 source reports this route and its unresolved interfaces. Its mathematical statement remains historical recorded evidence; the v52 update does not infer completion from omission. Source-reported live engine with explicit unresolved interfaces; it is not a completed route to the conjecture.
- Active routeRetained v20 route: R-E continuous-lift bypassThe retained v20 source reports this route and its unresolved interfaces. Its mathematical statement remains historical recorded evidence; the v52 update does not infer completion from omission. Source-reported live engine with explicit unresolved interfaces; it is not a completed route to the conjecture.
- Active routeThree-contact continuum and total collisionThe boundary route starts from square-freeness and HUG-WRAP, reaches an exact global three-contact continuum, and then has geometric, degree/return, size-coupling and cap-approximation branches. Its live work is to exclude same-continuum total collision, handle the conditional return alternatives, or obtain global cap compatibility. All-zero return degrees and the distinct scale/chord-parameter regimes remain; no path, unnamed action comparison or complete all-Jordan terminal is supplied.
- Active routeActual QSI and detector variationThe unmarked detector route requires actual QSI-1 implementation, including coherent natural maps and lifted/localized values, before its first natural image threshold and angular comparison can be used at the displayed finite-constructible scope. Marked QSL-1C/AI-RISK remains a separate unresolved source interface. Positive profile value or endpoint increase does not force positive square-angle slope, and abstract flat models do not settle actual geometric realization or preservation of first detection through switches.
- Active routeRestricted primitive and positive-response routesThe primitive route uses the displayed common-support ambient budget or finite hull-area variation with selected simple polygons, retaining AI-CPL and AI-RISK; UAP-1 retires the unrestricted universal-budget construction while restricted or square-free-conditional constructions remain. The distinct smooth-response route uses its GL-SM-based formulas only with actual positive bounded-probe or controlled endpoint variation. Critical primitive regularity, unsigned hull accumulation, weak averages or a positive spectral value do not supply those missing inputs or full-target exhaustion.
- Active routeComplete charged-family alternativesThe charged-family route retains both cofinal exact-critical states and one regular full-tail spine at the source's fixed-action scope. The regular branch keeps physical-cap variation or concentration, both stopping alternatives, complete frontier or coherent corridor, and bounded/unbounded energy and cap-product cases. Its circumcircle terminal needs actual full-tail absolute variation or physical cap uniform integrability on one coherent family. First-hit graph estimates, projected inverse concentration, kinematic examples or tangent concurrence do not supply all missing premises or COV-1.
How to interpret these counts
A statement may be a lemma, conditional reduction, special case, documented limitation, or open target. These counts describe the work's structure; they do not estimate distance to a proof.
Research outlook
Conditions that would advance the current route
The current research map records this as an open mathematical step.
A result can change the outlook by closing the bridge, narrowing its scope, or showing that the route cannot work.
- Supply the missing mathematical implication with all stated source hypotheses and retained boundary cases.
- Retain exact evidence for an independent source-fidelity and mathematical review; a model, calculation or branch-only result does not complete the full target.
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Inscribed Square Problem · ready to start
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Must every simple closed curve in the plane pass through the four corners of a square? The current research follows configurations with three corners on the curve and the fourth inside. It reports a connected family across all source separations and a coupling that prevents the second configuration from being smaller than the first. Both sizes can still collapse to zero. Conditional fixed-action, detector and regular-subclass methods remain separate routes, and none currently covers every Jordan curve.
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Sources and references2 cited works · next context review by Nov 21, 2026
The mathematical context was checked on Aug 21, 2026. Status can be refreshed sooner after a material result or claim.
- 1Floer homology and square pegspreprint · Joshua Evan Greene, Andrew Lobb · arXiv · 2024 · accessed Aug 21, 2026
- 2The rectifiable rectangular peg problempreprint · Tomohiro Asano, Yuichi Ike · arXiv · 2024 · accessed Aug 21, 2026
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