{"id":"ed00931f-dcf0-4f22-b012-e0a2bab0c56d","arxiv_id":"2506.16939","paper_version":2,"verdict":"REJECT","confidence":"MODERATE","novelty_score":4.0,"correctness_risk":"high","formal_verification":"none","parameter_count":3,"one_line_summary":"The paper sketches a scenario in which evaporating black holes never form a true event horizon, so quasilocal charges can carry information out and prevent information loss.","lead":"A physicist proposes that evaporating black holes never form a genuine one-way event horizon, but instead a temporary, two-way traversable 'dynamical horizon' allows energy and information to leak out. If correct, quantum information would survive black hole evaporation, potentially resolving a decades-old paradox.","discovery_kind":"extension","skeptic_critique":{"model":"deepseek-v4-flash","headline":"Central claim rests on the assumed late-time Minkowski mode limit (49)-(52), transferred from a Vaidya toy model to a semiclassically evaporating black hole without derivation from the semiclassical Einstein equations.","rationale":"The reader's weakest assumption is precisely that the late-time Minkowski mode convergence and κ^{-1}→0 are assumed from the Vaidya toy model rather than derived from semiclassical gravity. My independent reading confirms this is the single load-bearing condition: equations (49)-(52) are the only step that turns the otherwise heuristic 'quasilocal charges carry information' picture into a claim of unitary evolution and no information loss. The classical Brown-York reduction to HPS charges (Eqs. (11), (16), Appendix A) is a genuine, reproducible derivation and deserves credit, but it does not address the quantum information claim. The paper itself flags the missing support: it explicitly states that no solution of the semiclassical Einstein equations for dynamical black holes is known, and it acknowledges that the semiclassical energy flux near the horizon is locally negative while the Vaidya flux is everywhere positive. That admission is decisive: the toy model on which (49)-(52) rest differs qualitatively from the semiclassical scenario in the very quantity that controls the mode evolution. The additional assumptions behind the generalized ANEC (44)-(45) are likewise stated to be uncheckable by explicit calculation. Because the central conclusion (no information loss, unitary S-matrix) has no independent support once (49)-(52) are removed, the REJECT verdict is appropriate. I agree with the reader rather than adding a new concern; nothing in the self-referential limitation statements or appendices changes the assessment.","tokens_in":28615,"tokens_out":1772,"duration_ms":16096,"concrete_test":"Construct or cite a concrete semiclassical model (e.g., a self-consistent solution of the semiclassical Einstein equations for a massless scalar field, or a controlled 1+1-dimensional dilaton-gravity model such as RST/BH which has explicit evaporating solutions) and compute the late-time mode functions and the surface gravity on the dynamical horizon. Check whether g_m → f_m^{(0)+} and κ^{-1} → 0 as the horizon area goes to zero. If in an existing exactly solvable evaporating model the late-time horizon mode overlaps with outgoing modes vanish instead, the convergence assumption (49) fails and the unitary conclusion (52) does not follow; if the modes do converge to Minkowski modes, the concern is resolved for that model.","verdict_should_be":"REJECT","load_bearing_attack":"The load-bearing step is in Sec. 2.3: the claim that the horizon modes and the asymptotic modes both converge to Minkowski modes, so (52) is purely outgoing and the Bogoliubov transformation is unitary. This convergence (49) and the limit κ^{-1}→0 (50) are demonstrated only for the Vaidya toy model in Appendix B, where M(v) is prescribed by hand (71) and vanishes on a finite interval. The paper itself states that no solution of the semiclassical Einstein equations exists to check the analogous behavior in a real evaporating black hole. The semiclassical scenario is also acknowledged to differ from Vaidya in exactly the relevant respect: the flux near the horizon is locally negative in the semiclassical case, not positive, so the mode analysis that yields (91) has no known counterpart. Moreover, the resolution of the event-horizon issue by assuming the horizon is a two-way traversable dynamical horizon is itself an input: no semiclassical solution is exhibited in which the horizon is timelike and two-way traversable for an extended period, and the ANEC-based arguments (44)-(45) ensure only positivity of certain flux integrals, not two-way traversability. Since (49)-(52) are the only quantitative basis for the claimed unitarity and information recovery, the central claim is not derived; it is an assumption transferred from a toy model despite acknowledged qualitative differences.","agreement_with_reader":"agree"},"referee_report":{"model":"deepseek-v4-flash","summary":"The manuscript pursues two goals. First, within the Brown-York quasilocal framework, it constructs charges Q±_f and Q±_Y in Sections 1.2–1.3 and Appendix A, arguing that in the large-sphere Bondi limit they reduce to the conserved supertranslation and superrotation charges of Hawking, Perry, and Strominger. Second, in Section 2 it replaces the classical stress-energy tensor by a renormalized semiclassical source, defines the semiclassical charges in Eqs. (46)–(48), and then describes an evaporation scenario in which no event horizon forms, the inner boundary is a two-way traversable dynamical horizon, and the scalar-field modes converge to Minkowski modes at late times via Eqs. (49)–(52). From this scenario the paper concludes that particle creation in nonstationary black hole spacetimes with locally defined dynamical horizons cannot cause information loss.","tokens_in":28902,"tokens_out":7614,"duration_ms":79145,"significance":"If the information-preservation claim were established, the paper would offer a concrete mechanism for unitarity in black hole evaporation and would connect it to quasilocal boundary charges. The Brown-York derivation of the HPS supertranslation and superrotation charges is a useful consistency check of known results, and the Vaidya mode analysis in Appendix B is carried out in detail. However, the central claim is not demonstrated: the late-time mode convergence that drives the argument is assumed rather than derived, and the paper itself states that no solutions of the semiclassical Einstein equations exist with which to check the required assumptions. The manuscript contains no machine-checked proofs, numerical simulations, or falsifiable quantitative predictions, and the information-recovery mechanism remains at the level of a heuristic scenario.","major_comments":[{"comment":"The information-preservation conclusion is not derived from the semiclassical Einstein equations. The only quantitative basis is the Vaidya toy-model calculation in Appendix B, where the mass function is prescribed by hand in Eq. (71) and the mode functions satisfy Eq. (91); these results are then promoted to a generic evaporating black hole in Eqs. (49)–(50). The manuscript states in Sec. 2.2 that no solutions of the semiclassical Einstein equations describing backreaction in dynamical black hole spacetimes are known and that \"it proves impossible to check the validity of the assumptions made by explicit calculations,\" and it notes in Sec. 2.3 that the semiclassical flux near the horizon is locally negative whereas the Vaidya flux is positive. Consequently, the convergence Eq. (49) and the limit Eq. (50), and therefore the purely outgoing decomposition Eq. (52) with the claimed unitary Bogoliubov transformation, are assumptions rather than consequences of the model. Since Eq. (52) is precisely the statement that no thermal Hawking radiation remains at late times, the conclusion that information is not lost is effectively built in.","section":"Sec. 2.3, Eqs. (49)–(52); Appendix B"},{"comment":"The assumption that a genuine event horizon never forms is also an input. The paper's argument that event horizons are teleological and therefore absent in an evaporating spacetime is a conceptual preference, not a derived property of a semiclassical solution; no solution of Eq. (37) is exhibited with a timelike, two-way traversable dynamical horizon throughout the evaporation. The ANEC relations (44)–(45), even under the two stated assumptions, only establish non-negativity of some integrated flux expressions; they say nothing about causal two-way traversability of the horizon or about the ability of modes from the trapped region to reach future null infinity. Thus the assertion that there is no causal obstruction for information to escape is unsupported by the equations presented.","section":"Sec. 2.3, dynamical-horizon scenario; Eqs. (44)–(45)"},{"comment":"It is not established that the semiclassical charges Q±_f carry the information that would be lost in the standard Hawking calculation. Equation (48) is an asymptotic integral over I± involving the news and the renormalized stress-energy; the text after Eq. (53) asserts that these charges reach future null infinity and satisfy the antipodal matching conditions, but no computation links the flux of Q±_f to the horizon modes g_k appearing in the decomposition Eq. (30). Without such a link, the statement that soft-hair charges mediate the information transfer is an interpretation rather than a result of the Brown-York derivation.","section":"Sec. 2.2, Eq. (48) and following"},{"comment":"The claim that the limiting Bogoliubov transformation is unitary is not demonstrated. Even if g_m → f_m^{(0)+} and f_m^+ → f_m^{(0)+}, one must show that the matrices α, β, γ, η in Eqs. (32)–(33) define a unitary map between the initial and final Fock spaces; the manuscript only states that \"only ingoing and outgoing Minkowskian field modes are being involved.\" The standard stationary calculation, Eq. (34), exhibits a nonzero β-map, and the dynamical calculation that would make β vanish in the limit is not supplied. This is another place where the key conclusion is assumed.","section":"Sec. 2.3, text near Eq. (52)"}],"minor_comments":[{"comment":"Numerous typographical and grammatical errors should be corrected, including \"contiuous,\" \"asssuming,\" \"previosuly,\" \"onclude,\" \"eludicated,\" and \"an an interior part.\"","section":"Throughout"},{"comment":"The null expansions Θ and Ξ are defined with Ξ = 0 imposed on a dynamical horizon, but later flux integrals such as Eqs. (40)–(43) treat Ξ as a variable; please clarify whether these are different foliations or a generalized horizon definition.","section":"Sec. 1.1"},{"comment":"The phrase \"future past infinity\" should be \"past null infinity,\" and the determinant q of the metric q_AB should be defined explicitly in Eqs. (54)–(55).","section":"Appendix A"},{"comment":"The Δ-term in Eq. (25) is introduced before it is defined; please provide its explicit expression or a precise reference.","section":"Sec. 1.4, Eq. (25)"},{"comment":"There are unmatched parentheses in the displayed equations for the semiclassical charges; the manuscript should be carefully proofread.","section":"Eqs. (46)–(47)"}],"recommendation":"reject","confidential_remarks":"I would not recommend inviting a major revision. The technically sound portion of the paper, the Brown-York reduction to known HPS charges, is a consistency check of existing results, while the new physical claim rests on conditions that the paper itself acknowledges cannot be checked with current semiclassical methods. The missing derivation is load-bearing, so the conclusion is an assumption rather than a result. The manuscript would also benefit from a thorough proofreading before any resubmission."},"author_rebuttal":null,"desk_editor":{"model":"deepseek-v4-flash","letter":"The thing to know about this paper is that it has two very different halves. The first half derives the Hawking-Perry-Strominger supertranslation and superrotation charges from Brown-York quasilocal boundary terms. That is a real piece of work: the reduction looks internally consistent, the large-sphere limit reproduces the known Bondi-mass and angular-momentum expressions, and the semiclassical charges in (48) are a natural formal extension. If you work on quasilocal charges, this is a useful cross-check between two formalisms. The author also deserves credit for being honest: Section 2.2 explicitly states that no solutions of the semiclassical Einstein equations for a dynamical black hole are known, so the assumptions cannot be checked, and the conclusions are repeatedly hedged with 'arguably' and 'should'. The reliance on the author's earlier papers [53,54] is appropriate, since the Brown-York framework is his prior work and this is a direct continuation.\n\nThe soft spot is the second half, and it is load-bearing. The no-information-loss conclusion rests on Eqs. (49)-(52): the claim that, as the black hole evaporates, the horizon modes converge to Minkowski modes and the surface gravity diverges (k^{-1}->0), so the late-time decomposition is purely outgoing and the Bogoliubov transformation is unitary. This is derived in Appendix B only for a Vaidya model with a hand-prescribed mass function (71). The transfer to a real semiclassically evaporating black hole is not derived; the paper itself notes that the semiclassical flux near the horizon is locally negative, unlike Vaidya's positive flux. Moreover, (52) is essentially the statement that no thermal radiation remains at late times, so using it to prove that information is not lost is circular. The two-way traversable dynamical horizon is also an input, not a consequence: the ANEC-based arguments give positivity of certain flux integrals, not traversability.\n\nSo the central claim is not supported by the derivations. That said, this is not a crank paper. The classical part is solid enough to survive peer review, and the quantum part, while not a derivation, is a clearly stated proposal. A referee could reasonably say that the conclusion does not follow, but the paper deserves a referee rather than a desk rejection. If the author ever produces an actual semiclassical model where (49) holds, that would be a different conversation.","headline":"A legitimate Brown-York re-derivation of HPS soft hair charges wrapped around an information-preservation scenario whose central mode-convergence assumption is imported from a Vaidya toy model.","tokens_in":29445,"tokens_out":3795,"would_cite":false,"duration_ms":41321,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":["83C57","83C47","83C30","83C45"],"pacs":["04.70.Dy","04.60.-m"],"model":"deepseek-v4-flash","headline":"The paper argues that a black hole that forms and completely evaporates never develops a genuine event horizon; only a two-way traversable dynamical horizon exists, and quasilocal supertranslation charges carry energy and information…","keywords":["black hole information paradox","dynamical horizon","future trapping horizon","Brown-York quasilocal charges","supertranslation soft hair","superrotation charges","Hawking radiation","event horizon"],"falsifier":"A concrete check is to compute the Bogoliubov coefficients between the early-time and late-time mode bases in the paper's Vaidya mass function (71) beyond leading order. If the particle-production matrix $\\beta_{kl}$ does not go to zero as the mass tends to zero, a thermal residue remains and the claimed purification does not occur; conversely, exact vanishing at $M\\to 0$ would support the unitary conclusion.","tokens_in":28329,"feed_emoji":"🕳️","tokens_out":14215,"duration_ms":131311,"temperature":0.7,"pith_summary":"The paper tries to dissolve the black hole information paradox by changing the horizon itself. It claims that a non-rotating black hole that forms, radiates, and fully evaporates never possesses a genuine one-way event horizon; instead it has a two-way traversable dynamical (future-trapping) horizon. Quasilocal Brown-York charges are derived that coincide, in the large-sphere limit, with the conserved supertranslation and superrotation charges of asymptotically flat gravity, and the paper argues that these charges transport energy and information out of the evaporating hole to null infinity. If the scenario is right, black hole formation and evaporation is a unitary, information-preserving process, and particle creation does not lead to loss of information.","feed_headline":"No event horizon forms in black hole evaporation","feed_subtitle":"Quasilocal supertranslation charges keep the horizon two-way traversable, so information can reach infinity.","key_machinery":"The load-bearing object is the dynamical (future-trapping) horizon: a hypersurface foliated by marginally trapped surfaces, with one null expansion zero and the other strictly negative, which replaces the global, teleological event horizon as the inner boundary of spacetime. The derivation proceeds through the Brown-York Hamiltonian for a bounded spacetime with a null time-flow vector field; varying the boundary term yields flux integrals that, in the Bondi gauge at null infinity, become the supertranslation and superrotation charges, plus quasilocal corrections to the Bondi mass-loss formula. The mechanism that is claimed to save information is the mode-convergence condition of Appendix B: as the mass tends to zero, $\\kappa^{-1}\\to 0$ and the horizon modes $g_k$ approach the outgoing Minkowski modes, so the field has the purely outgoing form (52) and the scattering transformation is unitary.","core_discovery":"The central discovery, stated on the paper's own terms, is that replacing the teleological event horizon by a quasilocal dynamical horizon changes the outcome of black hole evaporation. The paper derives quasilocal Brown-York charges that reduce at infinity to the supertranslation and superrotation charges of the asymptotic symmetry algebra, then uses the semiclassical Einstein equations to extend them to the quantum regime as charges sensitive to backreaction. In the Vaidya-like model of collapse and complete evaporation, the horizon's surface gravity obeys $\\kappa^{-1}\\to 0$ as the mass tends to zero, so the horizon modes converge to Minkowski modes and the scalar field admits a purely outgoing decomposition with a unitary Bogoliubov transformation. The paper concludes that particle creation effects in nonstationary spacetimes with locally defined dynamical horizons cannot cause information loss at the quantum level.","pith_inferences":["Editorial inference: if the mechanism is right, information begins leaking during the entire nonstationary phase, not just at the end of evaporation, because the horizon is two-way traversable from the moment it forms; the paper does not quantify how much information exits early versus late.","Editorial inference: the same mode-convergence test could be applied to rotating dynamical horizons; angular momentum changes the surface gravity and could slow the $\\kappa^{-1}\\to 0$ convergence, which would be a concrete way to sharpen or falsify the scenario.","Editorial inference: the quasilocal charge flow suggests an observable tie to gravitational memory; the escaping energy flux should leave a memory signal different in angular structure from the classical one, though the paper only gestures at laboratory verification.","Editorial inference: standard entropy-curve computations usually fix the Cauchy surface as future null infinity plus the black hole interior; in this picture the traversable horizon changes the surface to future null infinity alone at late times, which would shift where unitarity is tested."],"forward_implications":["If the central claim is correct, black hole formation and complete evaporation is a unitary process: the information in the initial collapsing state reappears, in scrambled form, in the radiation at future null infinity.","Hawking radiation from an evaporating dynamical horizon is not thermal at late times; thermal emission with a Planck spectrum is a feature of stationary horizons and disappears once the mass approaches zero.","The supertranslation and superrotation charges are not merely asymptotic bookkeeping: their quasilocal versions carry energy and information through the dynamical horizon to infinity, which is the physical channel that prevents information loss.","The antipodal matching conditions can be satisfied in the dynamical-horizon setting, removing the horizon charge obstruction that encodes information loss in the standard event-horizon picture.","The first law and Smarr formula for stationary black holes emerge as special cases of the same quasilocal Hamiltonian, so the new picture remains consistent with standard black hole thermodynamics."],"supporting_citations":[{"why":"supplies the particle-creation mechanism and thermal spectrum whose information loss the paper aims to remove.","marker":"[43]"},{"why":"provides the supertranslation and superrotation charges that the quasilocal charges must reproduce at infinity, and the antipodal matching conditions.","marker":"[46]"},{"why":"defines dynamical horizons and their laws; the inner boundary of the paper's spacetime is such a horizon.","marker":"[6, 7]"},{"why":"supplies the evaporation scenario where a dynamical or future-trapping horizon replaces the event horizon and lets radiation escape to infinity.","marker":"[1, 49]"},{"why":"gives the Hamiltonian variation and quasilocal corrections to the Bondi mass-loss formula that the charge derivation extends.","marker":"[54]"},{"why":"provides the isolated-horizon framework recovered as the stationary special case, anchoring the surface-gravity and first-law identifications.","marker":"[2, 3, 7]"},{"why":"supplies the supertranslated Vaidya analogue used in Appendix B to test the late-time mode behavior.","marker":"[29]"},{"why":"gives the evaporating-black-hole surface-gravity relation used to show $\\kappa^{-1}\\to 0$ in the toy model.","marker":"[10, 80]"}],"fun_headline_variants":["Dynamical horizons let black hole information escape","No event horizon: information escapes during evaporation","Soft hair and dynamical horizons prevent information loss","Two-way traversable horizon releases black hole information","Quasilocal charges show black hole information escapes"],"cache_read_input_tokens":3200,"weakest_assumption_plain":"The entire conclusion rides on an assumption the paper states openly: that at the end of a real semiclassical evaporation the horizon modes behave as in the Vaidya toy model, with $\\kappa^{-1}\\to 0$ and all modes converging to Minkowski modes so the field becomes purely outgoing; the paper concedes that no solution of the semiclassical Einstein equations for a dynamical black hole is known that would establish this.","fun_headline_variants_meta":{"raw":{"variants":["Dynamical horizons let black hole information escape","No event horizon: information escapes during evaporation","Soft hair and dynamical horizons prevent information loss","Two-way traversable horizon releases black hole information","Quasilocal charges show black hole information escapes"]},"model":"deepseek-v4-flash","effort":"low","cost_usd":0.001216,"raw_usage":{"total_tokens":4959,"prompt_tokens":857,"completion_tokens":4102,"prompt_tokens_details":{"cached_tokens":384},"prompt_cache_hit_tokens":384,"prompt_cache_miss_tokens":473,"completion_tokens_details":{"reasoning_tokens":4032}},"tokens_in":473,"tokens_out":4102,"duration_ms":35551,"temperature":1.0,"reasoning_tokens":4032,"cache_read_input_tokens":384,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-08-15T19:16:26.167859+00:00","model_set":{"reader":"deepseek-v4-flash"},"falsifier":"A concrete check is to compute the Bogoliubov coefficients between the early-time and late-time mode bases in the paper's Vaidya mass function (71) beyond leading order. If the particle-production matrix $\\beta_{kl}$ does not go to zero as the mass tends to zero, a thermal residue remains and the claimed purification does not occur; conversely, exact vanishing at $M\\to 0$ would support the unitary conclusion.","supporting_citations":[{"cited_title":"Super- rotation charge and supertranslation hair on black holes.Journal of High Energy Physics, 2017(5):1–33, 2017","cited_arxiv_id":null,"evidence_quote":"provides the supertranslation and superrotation charges that the quasilocal charges must reproduce at infinity, and the antipodal matching conditions."},{"cited_title":"Quasilocal corrections to Bondi s mass-loss formula and dynamical horizons","cited_arxiv_id":null,"evidence_quote":"gives the Hamiltonian variation and quasilocal corrections to the Bondi mass-loss formula that the charge derivation extends."},{"cited_title":"Soft hair of dynamical black hole and hawking radiation","cited_arxiv_id":null,"evidence_quote":"supplies the supertranslated Vaidya analogue used in Appendix B to test the late-time mode behavior."}],"review_version":2}