{"id":"eeafdcdb-bc33-40b2-b903-339333b96cd7","arxiv_id":"2607.26932","paper_version":1,"verdict":"CONDITIONAL","confidence":"HIGH","novelty_score":5.0,"correctness_risk":"medium","formal_verification":"none","parameter_count":6,"one_line_summary":"Quasi-potential watershed voids in FLAMINGO J-PAS mocks remain size- and shape-consistent under photo-z errors, recover ~63% of thresholded volume, and preserve massive void-galaxy environmental trends.","lead":"A quasi-gravitational potential plus watershed void finder recovers dynamically dominant cosmic voids in J-PAS-like photometric mocks despite redshift smearing, and massive void galaxies still look bluer and more star-forming than equal-mass galaxies in dense regions. That matters because upcoming wide photometric surveys need a practical way to do void science without full spectroscopy.","discovery_kind":"new_application","skeptic_critique":{"model":"grok-4.5","headline":"No significant objection beyond the reader's already-flagged systematics gap; the mock-level claim holds.","rationale":"The paper delivers a clean, well-documented mock test that the quasi-potential watershed plus Φ>0 cut stabilises dynamically dominant voids and massive void-galaxy trends under the specific photo-z error model. Evidence quality (paired catalogues, multiple statistics, recovery correlations, bootstrap galaxy-property intervals) is adequate for that claim. The reader's CONDITIONAL verdict already prices in the deferred systematics and missing method calibration; no internal inconsistency or hidden assumption in the mock comparison itself rises to a stronger objection. A modest realism test (mask + selection) is the natural next check but does not require changing the verdict now.","tokens_in":30130,"tokens_out":524,"duration_ms":10843,"concrete_test":"Re-run the full pipeline on the same FLAMINGO snapshot after applying a simple angular mask + radial selection function approximating early J-PAS footprint depth variation; recompute the IoU-matched recovery fraction and the KS p-values on D_max and ellipticity. If recovery volume falls below ~40% of the thresholded quasi-potential or KS tests on size/shape reject at p<0.05, the readiness claim weakens; otherwise the mock result is robust to that layer of realism.","verdict_should_be":"UNCHANGED","load_bearing_attack":"No additional load-bearing concern identified that would overturn the central mock demonstration. The strongest claim is carefully scoped to a controlled FBI vs JP comparison under J-PAS-like line-of-sight errors: quasi-potential watershed voids (Φ>0 threshold, 1 Mpc grid, log-density Poisson solve) yield compatible size/ellipticity distributions, recover ~425 matched voids (~63% of FBI thresholded volume) with high Spearman correlations, and preserve massive void-core galaxy trends (lower M*, bluer colours, elevated SFR/sSFR at fixed mass). The reader's weakest assumption correctly isolates the forward leap to real J-PAS readiness (omitted masks, selection, full p(z), RSD; calibration deferred to McCarthy et al. in prep.). Within the paper's stated scope that leap is already caveated (§2.2, §3.2, §6), so it does not undermine the mock evidence itself. Secondary limitations (M*≥10^10 cut, IoU>0.5 recovery definition, spherical core selection) are acknowledged and do not invert the reported FBI–JP agreement.","agreement_with_reader":"agree"},"referee_report":{"model":"grok-4.5","summary":"The paper tests whether a quasi-gravitational potential (Poisson solve on ln(1+δ) from a DTFE galaxy density field), followed by a Φ>0-thresholded watershed, can identify dynamically dominant voids in FLAMINGO-based J-PAS mocks despite photometric redshift errors. Comparing an ideal FBI mock to a JP mock with J-PAS-like line-of-sight scatter at z=0.3 and mi<20, the authors report compatible void size and ellipticity distributions, recovery of ~425 matched voids (IoU>0.5) occupying ~63% of the FBI thresholded quasi-potential volume with strong object-by-object Spearman correlations, and preservation of expected massive void-core galaxy trends (lower M*, bluer colours, elevated SFR/sSFR at fixed mass) relative to a high-density comparison sample. The main photo-z impact is interior contamination of JP density profiles and a modest drop in void abundance.","tokens_in":30505,"tokens_out":1549,"duration_ms":35734,"significance":"If the controlled mock result holds, the work offers a practical path for void and void-galaxy science in narrow-band photometric surveys such as J-PAS, where raw density-based void finders are known to degrade under photo-z scatter. The FBI–JP design, dual size estimators (Req and Dmax), KS and Spearman tests, spherical plus boundary density profiles, and mass-binned galaxy property comparisons with bootstrap intervals constitute a clear, falsifiable demonstration within the stated scope. Strengths include the explicit differential mock test, the dynamical motivation for restricting to expanding Φ>0 basins, and candid caveats on deferred systematics and the M*≥10^10 cut. The result is incremental rather than transformative, but useful for the community preparing J-PAS and similar surveys.","major_comments":[{"comment":"§3.2 and §6 state that grid resolution, log-transform, and the quasi-potential threshold (exclude −Φ≥0) are not calibrated here and are deferred to McCarthy et al. (in prep.). The central claim that the method ‘mitigates redshift errors’ and yields ‘reliable’ voids therefore rests on a single fixed parameter set (1 Mpc grid, Φ>0 cut, ~55–56% volume occupation). Without at least a limited sensitivity check in this manuscript (e.g., threshold variation and effect on KS p-values, recovery fraction, and stacked profiles), it is hard to judge how load-bearing those choices are for the reported FBI–JP agreement. A short appendix or table quantifying stability under modest threshold/grid changes would substantially strengthen the robustness claim.","section":"§3.2, §6"},{"comment":"§4.3 and §5.1 document clear photo-z contamination of JP void interiors (elevated central 1+δ; SMF excess above ~10^11 M⊙; fewer void-core galaxies because collecting spheres shrink). The galaxy-property conclusions in §5.2 (bluer colours, higher SFR/sSFR at fixed mass) are drawn from the full JP void-core sample, not the 8990 ID-matched galaxies common to FBI and JP. Given that contamination is the dominant photo-z effect, the paper should either (i) repeat Fig. 12 on the matched subset or (ii) quantify how much the JP–high-density contrast shrinks when contaminants are removed. Without that, the claim that ‘expected trends survive’ in the JP mock is only partially stress-tested.","section":"§5.1–5.2, Fig. 12"},{"comment":"§3.3–4.5 define recovery via IoU>0.5 and report 425 recovered voids (~40% of FBI voids; ~63% of FBI thresholded volume) with high Spearman rs for Dmax and ellipticity. The abstract and conclusions call this a ‘reasonable number’ and evidence that voids are ‘reliably’ identified. The paper should state more explicitly what success criterion was set a priori (volume fraction? purity/completeness vs size?) and how sensitive the 63% figure is to the IoU cut (e.g., IoU>0.3 vs 0.5). As written, ‘reasonable’ is post hoc and weakens the quantitative recovery claim.","section":"§3.3, §4.5, Abstract"}],"minor_comments":[{"comment":"Fig. 3 caption and body: watershed boundaries are said to be shown in a 5 Mpc-thick slice in one place and 1 Mpc in another; clarify slice thickness consistently for density vs quasi-potential panels.","section":"Fig. 3"},{"comment":"Eq. (5) and surrounding text: the quasi-potential is defined via Poisson on ln(1+δ), but the symbol Φ is used for both the standard and quasi potential. Introduce a distinct symbol (e.g. Φ_q) to avoid confusion when discussing Φ>0 thresholds.","section":"§3.2"},{"comment":"§2.2: the J-PAS calibration sample is restricted to well-defined primary peaks and 0.2<z<0.4, mi<20; the text correctly notes it may not represent the full J-PAS population. A one-sentence quantitative comparison of the error distribution to the broader miniJPAS/TOPz sample would help readers gauge selection bias.","section":"§2.2"},{"comment":"§4.2: KS test on Req rejects equality (p=0.0012) while Dmax does not (p=0.065). The text correctly prefers Dmax, but the abstract’s ‘overall size … distributions agree well’ should briefly acknowledge the Req tension so it is not overstated.","section":"Abstract, §4.2"},{"comment":"Typos/notation: ‘J-P AS’ spacing inconsistencies in title/headers; ‘goaldz’ in §2.1; ‘Superhubble Bubbles’ may need a brief definition or citation call-out on first use beyond Icke 1984.","section":"Title, §2.1, §3.2"},{"comment":"Fig. 7–8 inset difference panels are useful; ensure axis labels and the sign convention (JP−FBI vs FBI−JP) are stated in the caption.","section":"Figs. 7–8"}],"recommendation":"minor_revision","confidential_remarks":"The manuscript is an application paper whose methodological core is deferred to McCarthy et al. (in prep.). That is acceptable if the present claims stay scoped to the FBI–JP mock test, which they largely do. I would not block on the missing calibration provided the authors add a minimal sensitivity check and tighten the recovery/galaxy-contamination language. Fit for A&A is good; novelty is moderate (quasi-potential watershed + J-PAS photo-z) but the controlled experiment is clean. No integrity concerns."},"author_rebuttal":null,"desk_editor":{"model":"grok-4.5","letter":"The one thing worth knowing is that this is a clean FBI-vs-JP mock test: Poisson solve on ln(1+δ), Φ>0 watershed threshold, and the usual DTFE grid, applied to FLAMINGO L1_m8 at z=0.3 with J-PAS-calibrated line-of-sight errors. Size and ellipticity distributions stay compatible, ~425 voids match at IoU>0.5 (~63% of the FBI thresholded volume) with high Spearman correlations, and the massive void-core galaxies still look lower-mass, bluer, and more star-forming at fixed M* than the high-density control.\n\nWhat is actually new is the quantitative application, not the ingredients. Watershed voids, potential basins, DTFE, and photo-z void problems are established; the paper’s contribution is the controlled comparison under explicitly J-PAS-like errors plus the void-core selection and the recovery statistics. They do the comparison properly: abundance, Req and Dmax, ellipticities with KS tests, spherical and boundary density profiles, object-by-object recovery, and mass-binned SFR/sSFR/colour with bootstrap intervals. The main photo-z damage is correctly diagnosed as interior contamination from scattered high-density galaxies, not wholesale destruction of the large expanding basins. Citations look appropriate and the differential design is not circular.\n\nSoft spots are real but already flagged by the authors and do not sink the mock claim. Method calibration (grid, log-transform, threshold) is deferred to McCarthy et al. in prep.; survey geometry, masks, selection, full p(z), and RSD are omitted by design (§2.2, §6). The M*≥10^10 cut means these are not the classic faint void population. IoU>0.5 and the spherical core cut are choices, not theorems. None of that overturns the FBI–JP agreement inside the stated scope.\n\nThis is for people building void pipelines for J-PAS/Euclid-style photo-z maps or checking whether environmental trends survive redshift smearing. It deserves a serious referee. I would engage with it and expect it to be cited in that niche; I would not desk-reject.","headline":"Solid controlled mock demo that quasi-potential watershed voids and massive void-galaxy trends hold under J-PAS-like photo-z errors; useful infrastructure, not a cosmology result, with the real-data leap already caveated.","tokens_in":31356,"tokens_out":554,"would_cite":true,"duration_ms":11535,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":["98.80.-k","98.65.Dx","95.75.Pq","98.62.Py"],"model":"grok-4.5","headline":"A quasi-gravitational potential can recover dynamically dominant voids and their galaxy trends despite J-PAS photometric redshift errors.","keywords":["cosmic voids","photometric redshifts","quasi-gravitational potential","watershed void finder","void galaxies","J-PAS","FLAMINGO","large-scale structure"],"falsifier":"Apply the identical pipeline to a larger mock that also includes survey geometry, masks, selection functions and full photo-z posteriors; if the recovered-void volume fraction collapses well below 63 percent or the void-versus-dense galaxy property trends disappear, the claim fails.","tokens_in":31024,"feed_emoji":"🌌","tokens_out":817,"duration_ms":16750,"temperature":0.7,"pith_summary":"Photometric surveys map huge volumes of galaxies cheaply, but redshift errors smear structures along the line of sight and wreck ordinary void finders. This paper shows that solving a Poisson equation on the log galaxy density produces a quasi-gravitational potential whose large-scale peaks mark the true expansion centres of the cosmic web. A watershed algorithm restricted to the expanding (positive) regions of that field finds voids whose sizes and shapes agree closely between an ideal mock and a mock with realistic J-PAS errors; a matched subset of voids even occupies most of the thresholded volume. Massive galaxies selected inside those voids still look less massive, bluer and more star-forming than equal-mass galaxies in dense regions. The result matters because it opens a practical route to void cosmology and environmental galaxy studies in the coming flood of photometric data.","feed_headline":"Photo-z errors need not erase cosmic voids","feed_subtitle":"A quasi-potential watershed recovers matching voids and galaxy trends in J-PAS mocks","key_machinery":"The quasi-gravitational potential: the Poisson solution of the log-transformed galaxy number density, thresholded to positive (expanding) regions and partitioned by watershed. It acts as a low-pass filter that isolates the dynamically dominant supervoids while suppressing small-scale noise introduced by photo-z scatter.","core_discovery":"In FLAMINGO mocks at z=0.3 with J-PAS-like photometric redshift errors, a watershed applied to a thresholded quasi-gravitational potential recovers dynamically dominant voids whose size and ellipticity distributions match those of the ideal mock, recovers a substantial matched subset occupying roughly 63 percent of the thresholded volume, and still yields massive void-core galaxies that are less massive, bluer and more star-forming than equal-mass galaxies in high-density regions.","pith_inferences":["The same potential watershed could serve as a common void definition across heterogeneous photometric and spectroscopic surveys, reducing finder-to-finder systematics.","Because the method already discards contracting regions, it may automatically suppress the void-in-cloud population that contaminates many cosmological void probes.","Extending the identical pipeline to Euclid-scale volumes would test whether the recovered volume fraction and galaxy trends remain stable when sample variance drops."],"forward_implications":["J-PAS and similar photometric surveys can host catalogues of dynamically dominant voids without waiting for complete spectroscopy.","Massive void-galaxy trends in colour, stellar mass and star-formation rate remain measurable at J-PAS photo-z precision.","Stacking analyses that rely on void centres (Alcock–Paczyński, ISW, weak lensing) become feasible on photometric samples once the quasi-potential filter is applied.","Smaller nested voids and void-in-cloud systems are deliberately excluded, so cosmological constraints will reflect only the expanding supervoid population."],"fun_headline_variants":["Quasi-potential recovers matching voids despite photo-z errors","Watershed voids keep size and shape under J-PAS redshift scatter","Void galaxies stay bluer and more star-forming in photo-z mocks","Dynamically dominant voids occupy 63% volume after error mitigation","FLAMINGO mocks show void trends survive J-PAS-like photo-z noise"],"cache_read_input_tokens":128,"weakest_assumption_plain":"That fixing the log-density transform, one-megaparsec grid and positive-potential threshold is already enough to claim the method will deliver reliable voids once real survey masks, selection functions and full redshift posteriors are included.","fun_headline_variants_meta":{"raw":{"variants":["Quasi-potential recovers matching voids despite photo-z errors","Watershed voids keep size and shape under J-PAS redshift scatter","Void galaxies stay bluer and more star-forming in photo-z mocks","Dynamically dominant voids occupy 63% volume after error mitigation","FLAMINGO mocks show void trends survive J-PAS-like photo-z noise"]},"model":"grok-4.5","effort":"low","cost_usd":0.004195,"raw_usage":{"total_tokens":1383,"prompt_tokens":917,"num_sources_used":0,"completion_tokens":77,"cost_in_usd_ticks":41948000,"prompt_tokens_details":{"text_tokens":917,"audio_tokens":0,"image_tokens":0,"cached_tokens":256},"completion_tokens_details":{"audio_tokens":0,"reasoning_tokens":389,"accepted_prediction_tokens":0,"rejected_prediction_tokens":0}},"tokens_in":917,"tokens_out":77,"duration_ms":8207,"temperature":1.0,"reasoning_tokens":389,"cache_read_input_tokens":256,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-07-30T16:34:52.933908+00:00","model_set":{"reader":"grok-4.5"},"falsifier":"Apply the identical pipeline to a larger mock that also includes survey geometry, masks, selection functions and full photo-z posteriors; if the recovered-void volume fraction collapses well below 63 percent or the void-versus-dense galaxy property trends disappear, the claim fails.","supporting_citations":[],"review_version":1}