How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
A lake at rest over a bump with a dry crest
Example
Take five periodic cells, , bed values , and free-surface level . Set and , so ; the crest cell is dry.
Facts & Assumptions
Given: The periodic five-cell bed and states above. Verify the exact one-step hydrostatic HLL update.
One-dimensional shallow-water balance law with a dry-state convention: on wet rest cells, and ; a dry cell has with .
Hydrostatic reconstruction with a dry-safe HLL flux and one-sided pressure corrections: each side corrected flux is the common HLL flux plus its cell pressure minus reconstructed pressure.
The hydrostatic HLL update preserves lakes at rest, including dry cells: if the reconstructed states at a face agree at rest, the cell-side corrections leave equal hydrostatic pressures on the two faces of each cell.
Verification
The data are admissible by [F1]. The four face maxima, including the periodic face between cells and , are , so the paired reconstructed depths are respectively , , , , and . All reconstructed velocities are zero.
At these equal states the common HLL fluxes are , , , and . Adding the one-sided pressure corrections in [F2] makes the two corrected fluxes adjacent to each cell both equal : the five cell pressures are .
Each cell therefore has zero corrected-flux difference in the update, so every state is unchanged, including the dry crest. This verifies the exact lake-at-rest preservation in [F3] for this finite wet/dry example.
Depends on
Used by
Nothing in the library uses this result yet.
Dependency tree · one level
3 results within one dependency step of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- E. Audusse, F. Bouchut, M.-O. Bristeau, R. Klein, and B. Perthame, A Fast and Stable Well-Balanced Scheme with Hydrostatic Reconstruction for Shallow Water Flows (standard reference, not scraped)
- F. Bouchut, III. Shallow water problem – Hydrostatic reconstruction scheme (standard reference, not scraped)