Fixing the dynamical evolution in scalar-Gauss-Bonnet gravity
Bibliographic record
Abstract
One of the major obstacles to testing alternative theories of gravity with gravitational-wave data from merging binaries of compact objects is the formulation of their field equations, which is often mathematically ill-suited for time evolutions. A possible way to address these delicate shortcomings is the fixing-the-equations approach, which was developed to control the behavior of the high-frequency modes of the solutions and the potentially significant flow toward ultraviolet modes. This is particularly worrisome in gravitational collapse, where even black hole formation might be insufficient to shield regions of the spacetime where these pathologies might arise. Here, we focus (as a representative example) on scalar-Gauss-Bonnet gravity, a theory that can lead to ill-posed dynamical evolutions, but with intriguing stationary black hole physics. We study the spherical collapse of a scalar pulse to a black hole in the fixing-the-equations approach, comparing the early stages of the evolution with the unfixed theory and the later stages with its stationary limit. With this approach, we are able to evolve past problematic regions in the original theory, resolve black hole collapse, and connect with the static black hole solutions. Our method can thus be regarded as providing a weak completion of the original theory, and the observed behavior lends support for considering previously found black hole solutions as a natural outcome of collapse scenarios.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.003 |
| Scholarly communication | 0.001 | 0.002 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".