{"id":"357ab290-de4c-40d8-af1b-2d60c70cc385","arxiv_id":"2411.14200","paper_version":1,"verdict":"CONDITIONAL","confidence":"MODERATE","novelty_score":5.0,"correctness_risk":"medium","formal_verification":"none","parameter_count":0,"one_line_summary":"Twisted holography is conjectured to extend from orbifolds to orientifolds, with bulk duals given by unoriented or oriented topological strings on SL2C/Γ, where orientifold data is encoded by a spin structure.","lead":"This paper organizes four-dimensional N=2 superconformal gauge theories arising from D3-branes at orientifolds and proposes new holographic dualities for their chiral algebras. If the conjectures hold, the protected operators of each such theory would be described by topological strings on a quotient of SL2C.","discovery_kind":"extension","skeptic_critique":{"model":"deepseek-v4-flash","headline":"The central leap is from the Z2 example to all ADE orientifolds: Sec. 3.2 does not show that orientation-reversing elements act only on the fermionic α,γ boundary conditions and leave the A/D complex-structure towers untouched for general Γ.","rationale":"The reader's weakest_assumption correctly identifies the load-bearing gap: the orientifold action after the Q+S twist is assumed to reduce to a quotient SL2C/Γ with orientation-reversing elements contributing only a Z2-bundle/spin structure, with the extrapolation from Z2 to all ADE groups unproven. My stress-test sharpens this concern in two ways. First, the Z2 check only compares parity of the A/B/C/D towers in a free-field cohomology; it does not provide the bulk action of αΩ' on BCOV fields, so it cannot justify the claim that complex-structure deformations (the Beltrami sector) are unaffected for nontrivial Γ. Second, the paper itself relies on a further conjecture that all Chan-Paton representations for a fixed orientifold group yield the same large-N chiral algebra; this is necessary for the bulk background to be determined by Γ alone, and it is not checked even for the next-simplest case. The proposed test, computing the Z4/G1=Z2 orientifold chiral algebra from the free-field construction and comparing it with the Z4 orbifold, is the minimal nontrivial check that would either support or falsify the spin-structure interpretation. I do not see grounds to reject the paper: it is explicitly framed as conjectural, it organizes a substantial class of constructions, and it provides one explicit worked example with a clear bulk interpretation. The appropriate verdict remains CONDITIONAL, matching the reader's assessment; my concern does not move the verdict, so I mark it UNCHANGED.","tokens_in":20036,"tokens_out":8107,"duration_ms":87508,"concrete_test":"Compute the large-N chiral algebra for the Γ=Z4, G1=Z2 orientifold (Sec. 2.4, k=2, using both Chan-Paton choices γ and γ~). Impose the orientifold projection (2.5)-(2.6) on the symplectic bosons and bc system, enumerate the A_n, B_n, C_n, D_n single-trace primaries, and compare with the pure Z4 orbifold. The spin-structure claim predicts that the A/D towers match the Z4 orbifold exactly while only the B/C tower parities are shifted by the choice of index-2 subgroup; any additional projection of A/D, or any difference between the two Chan-Paton representations, would disprove the 'simply SL2C/Γ with a spin structure' characterization.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The paper's central claim is the identification of the twisted bulk with SL2C/Γ (O3 case) or unoriented topological strings on SL2C/G1 (O7 case), with orientifold data reduced to a Z2-bundle/spin structure. The only substantive check is the Γ=Z2 example in Sec. 3.2: from Eqs. (3.1)-(3.3), the Z2 orbifold keeps the four single-trace towers at even n, while the SO(N)/USp(2N) orientifold keeps A_n,D_n for even n and B_n,C_n for odd n. The paper then asserts that in general the orientation-reversing elements only twist boundary conditions for the fermionic Chern-Simons fields α,γ, leaving the Beltrami differential sector (the A/D towers) unchanged. This is an extrapolation from one parity computation in a free chiral algebra to an unstated action of αΩ' on BCOV/Kodaira-Spencer theory. For Γ with nontrivial α, the action of the orientifold element on the complex structure of SL2C/Γ and on β is not derived, so the claim that the background is 'simply SL2C/Γ' is not established. The problem is compounded by the multiple Chan-Paton representations for the same (Γ,G1) in Secs. 2.4-2.6: the paper conjectures they give the same large-N chiral algebra, but if the orientifold projection depends on the representation, the bulk cannot be determined by the orientifold group alone. The O7 claim inherits the same gap: localization onto the O7-plane and reduction to unoriented strings on SL2C/G1 are stated, not computed, with the SO(8) global symmetry as the only direct evidence. Since Sec. 4 explicitly defers proofs to future work, this is an admitted conjecture rather than an internal inconsistency, but the conjecture's key structural assumption is tested in only one case.","agreement_with_reader":"partial"},"referee_report":{"model":"deepseek-v4-flash","summary":"The paper proposes twisted holographic duals for the chiral algebras associated to a large class of four-dimensional N=2 superconformal gauge theories realized by D3-branes on orientifolds. For O3-plane orientifolds with orientifold group Γ and orientation-preserving subgroup G1, the proposal is that the bulk dual is topological string theory on SL2C/Γ, with the orientation-reversing elements encoding a Z2-bundle or spin structure that affects only certain fermionic boundary conditions. For O7-plane orientifolds of the form ZΩ'_2 × G1, the proposal instead involves unoriented topological strings on SL2C/G1, with the boundary chiral algebra carrying an SO(8) Kac-Moody symmetry. Section 2 organizes the orientifold constructions and their quiver gauge theories, while Section 3 develops the proposed dualities. The only concrete computation is the Γ = Z2 example in Section 3.2, where trace identities show that the SO/USp orientifold chiral algebras keep the A_n and D_n towers at even n and the B_n and C_n towers at odd n, thereby distinguishing them from the Z2 orbifold theory. The paper is explicit that the general dualities are conjectures to be proven in future work.","tokens_in":20435,"tokens_out":4361,"duration_ms":44840,"significance":"If the conjectures are correct, the paper extends the twisted holography program of Costello and Gaiotto to a broad set of orientifold theories, including a proposal involving unoriented topological strings, which would be a novel holographic arena. The paper is commendably transparent: it has no free parameters, it clearly labels the central dualities as conjectures, and it provides one explicit, clean check in the Z2 case. The observation that the SO/USp and Z2-orbifold chiral algebras share the A and D towers but differ in the B and C towers is a useful and falsifiable diagnostic. However, the significance is currently limited by the fact that all load-bearing steps beyond the Z2 example are asserted rather than derived, so the paper reads more as a research announcement than as a completed duality proposal.","major_comments":[{"comment":"The central step from the Z2 example to general O3 orientifolds is not established. The paper shows in Eqs. (3.1)-(3.3) that the SO/USp projection keeps A_n and D_n for even n and B_n and C_n for odd n, and then states that in general the choice of index-2 subgroup is a Z2-bundle/spin structure that changes only the boundary conditions of the fermionic Chern-Simons fields α and γ, while the A and D towers, tied to the Beltrami differential and complex structure, are unchanged. This is an extrapolation from a free-chiral-algebra parity computation to a statement about the action of αΩ' on BCOV/Kodaira-Spencer theory for nontrivial α. No such action is computed or even defined for a non-cyclic Γ. Since the claim that 'the resulting background is simply SL2C/Γ' rests on this premise, the paper should either derive this for at least one non-cyclic example or explicitly demote it to a conjecture with a concrete test (e.g., matching the projected single-trace towers against a bulk computation of boundary-condition-changing operators).","section":"Sec. 3.2, after Eq. (3.3)"},{"comment":"The O7 proposal is stated but not derived. The paper asserts that upon twisting the IIB theory localizes entirely onto the O7-plane and that the local physics is described by unoriented topological strings, with the USp(2N) theory plus antisymmetric and four fundamentals as the boundary dual. The only direct evidence offered is the SO(8) flavor symmetry matching the SO(8) holomorphic Chern-Simons theory on space-filling branes. Since this is one of the two central families of dualities, the absence of any computation of the single-trace chiral algebra or of the bulk localization means the claim currently has the status of an analogy. Please either provide supporting evidence or clearly mark the entire O7 family as a conjecture separate from the O3 case, and state what would be needed to test it.","section":"Sec. 3.1"},{"comment":"The paper's conjecture that all quivers belonging to the same orientifold group give the same large-N chiral algebra is load-bearing for the claim that the bulk is determined entirely by the orientifold group. However, the orientifold projection depends on the chosen Chan-Paton representation, and different representations give different quivers, e.g. Eq. (2.25) versus Eq. (2.26) for ZαΩ'_8 lead to different gauge-group factors and matter representations. The paper provides no computation showing that the projected single-trace spectra coincide in the large-N limit, and no example beyond the SO/USp duality of the Z2 case. Without this, the map from a given field theory to a unique bulk is ambiguous. This needs either proof for a nontrivial example or an explicit caveat that the bulk assignment is part of the conjecture.","section":"Sec. 2.2-2.6 and end of Sec. 3 introduction"}],"minor_comments":[{"comment":"The text says that for sp(2N) 'the same equation holds' and writes M_i^T = -Ω M_i Ω^{-1}, but the displayed trace relation would be clearer if the conjugation by Ω were carried through explicitly; the final parity conclusion is correct, but the intermediate step is abbreviated.","section":"Sec. 3.2, Eq. (3.3)"},{"comment":"Typo: 'tractible' should be 'tractable' in the final bullet point.","section":"Sec. 4"},{"comment":"The block matrix Ω_m is defined only implicitly; stating its size explicitly (m/2 × m/2 blocks) would improve readability, especially since the same symbol recurs in later sections.","section":"Sec. 2.2, Eq. (2.14)"},{"comment":"The tables list conformal rank assignments but do not fully specify the hypermultiplet representations for every node; referring explicitly to the equation numbers for the Chan-Paton representations in each row would make the tables more self-contained.","section":"Tables 2-4"}],"recommendation":"major_revision","confidential_remarks":"The paper is a short, openly conjectural note. Its main value is in organizing orientifold constructions and proposing a concrete, parameter-free extension of twisted holography, but the central extrapolations are currently unsupported. I do not see grounds for rejection, since the claims are hedged and the Z2 check is sound; however, the manuscript should either strengthen the derivations for a nontrivial example or more precisely delimit what is conjecture and what is established. The citation and attribution practices seem appropriate."},"author_rebuttal":null,"desk_editor":{"model":"deepseek-v4-flash","letter":"Dear colleague,\n\nThe paper proposes twisted holographic duals for large-N N=2 SCFTs from D3-branes at orientifolds: the bulk is topological strings on SL2C/Γ for O3-planes, and unoriented topological strings on SL2C/G1 for O7-planes. What's genuinely new is the claim that orientifold data survives the twist as a choice of spin structure—a Z2-bundle over SL2C/Γ—and the explicit Z2 computation showing this matters. The paper is honest that the dualities are conjectures.\n\nThe strengths: it's a clean organization of the orientifold constructions, and the one concrete check in Sec. 3.2 is correct. The trace identities show that the Z2 orbifold keeps A_n,D_n for even n and B_n,C_n for odd n, while SO/USp keeps A,D for even and B,C for odd. That's a real, independent Z2 invariant of the chiral algebra that distinguishes orbifold from orientifold, and it matches the claimed bulk picture: the A/D towers (Beltrami/complex structure) are untouched, while the B/C towers (fermionic Chern-Simons fields) see twisted boundary conditions. That's a nice piece of evidence.\n\nThe soft spots are exactly where you'd expect. The extrapolation from Z2 to all ADE subgroups is assumed, not derived. The paper asserts that orientation-reversing elements act only on the fermionic boundary conditions for general Γ, but it doesn't show that the action on the bulk BCOV/Kodaira-Spencer theory is that simple—especially the action on the Beltrami differential and on β for nontrivial α. The O7 localization claim is also stated rather than computed; the SO(8) global symmetry is suggestive but not a derivation. And the multiple Chan-Paton representations for the same (Γ,G1) are conjectured to give the same large-N chiral algebra, but if the projection depends on the representation, the bulk can't be fixed by the group alone. These are not fatal flaws, because the paper explicitly frames them as conjectures and leaves proofs for future work, but they mean the central claim is supported by one example plus plausibility.\n\nWho's it for: anyone working on twisted holography or protected sectors of N=2 SCFTs. It deserves a serious referee—the conjecture is coherent, the Z2 check is solid, and the paper maps out a research program. I'd send it to review, with the expectation that the referee will push for either a second nontrivial example or a derivation of the spin-structure boundary conditions in the bulk. I wouldn't desk-reject it; it's the kind of paper that generates follow-ups.\n\nBest.","headline":"A transparent conjecture paper with one solid parity check; worth refereeing, but the leap from Z2 to all ADE orientifolds is the soft spot.","tokens_in":20980,"tokens_out":3077,"would_cite":false,"duration_ms":28796,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"deepseek-v4-flash","headline":"The paper proposes that the protected chiral algebra of any $\\mathcal{N}=2$ superconformal gauge theory from an orientifold has a twisted-holographic dual: topological string theory on $\\mathrm{SL}_2\\mathbb{C}/\\Gamma$, with the…","keywords":["N=2 superconformal field theory","chiral algebra","twisted holography","orientifold","topological string","Kodaira-Spencer theory","BCOV theory","D3-branes"],"falsifier":"Compute the large-$N$ chiral algebra of a nontrivial ADE orientifold theory, for instance the binary tetrahedral O3 orientifold or the O7 theory with $\\Gamma=\\mathbb{Z}_2^{\\Omega'}\\times\\mathbb{Z}_3$, and compare the B and C operator towers, or the full characters, with the prediction of Kodaira-Spencer theory on $\\mathrm{SL}_2\\mathbb{C}/\\Gamma$ with the claimed spin-structure boundary conditions; a mismatch in parity, multiplicity, or level would settle the proposal against the extrapolation from the $\\mathbb{Z}_2$ case.","tokens_in":19844,"feed_emoji":"🌀","tokens_out":14344,"duration_ms":108837,"temperature":0.7,"pith_summary":"Four-dimensional $\\mathcal{N}=2$ superconformal gauge theories that admit a weakly coupled limit can be built by placing D3-branes on orientifold singularities, and each such theory carries a protected subsector that forms a two-dimensional chiral algebra. This paper proposes that, in the large-$N$ limit, that chiral algebra has a twisted-holographic dual: topological string theory, whose spacetime physics is Kodaira-Spencer (BCOV) theory, on the Calabi-Yau threefold $\\mathrm{SL}_2\\mathbb{C}/\\Gamma$, with $\\Gamma$ the finite orientifold group. For orientifolds containing an O7-plane, the dual is instead the unoriented topological string on $\\mathrm{SL}_2\\mathbb{C}/G_1$, because the twist localizes the theory onto the O7-plane. The paper's central observation is that orientation-reversing elements of the orientifold leave the bulk complex structure unchanged and manifest themselves only as a choice of spin structure, meaning twisted boundary conditions for the fermionic fields in the bulk, which distinguishes these chiral algebras from ordinary orbifold theories on the same space. If the proposal is right, it supplies a holographic interpretation for a large family of $\\mathcal{N}=2$ quiver gauge theories and shows that orientifold data survive the twist in a precise, computable form.","feed_headline":"Twist maps orientifold N=2 theories to topological strings on SL2C/Γ","feed_subtitle":"The protected chiral algebra is dual to Kodaira-Spencer theory, with orientifold data in a spin structure.","key_machinery":"The machinery is the $Q+S$ twist: a nilpotent supercharge built from a supersymmetry generator $Q$ and a superconformal generator $S$, whose cohomology selects the protected local operators of the four-dimensional theory and makes them into a two-dimensional chiral algebra, a set of operators depending holomorphically on one coordinate with crossing-symmetric OPEs. On the gravity side, twisting supergravity corresponds to turning on a bosonic ghost background, and for type IIB superstrings it produces the spacetime physics of the B-model topological string, namely Kodaira-Spencer (BCOV) theory. The proposal is that in these orientifold backgrounds the bulk theory lives on the quotient $\\mathrm{SL}_2\\mathbb{C}/\\Gamma$, with the orientation-reversing elements of $\\Gamma$ realized as a $\\mathbb{Z}_2$-bundle, a spin-structure choice, that changes only the boundary conditions of the fermionic fields $\\alpha$ and $\\gamma$, while the Beltrami differential $\\beta$ (the complex-structure deformation) is insensitive to it. For O7 orientifolds the same twist collapses the theory onto the O7-plane, where the relevant bulk theory is the anomaly-free unoriented topological string on $\\mathrm{SL}_2\\mathbb{C}/G_1$.","core_discovery":"The central claim is that the chiral algebra associated to any of these $\\mathcal{N}=2$ superconformal orientifold theories is holographically dual, in the large-$N$ limit, to topological strings on a Calabi-Yau threefold of the form $\\mathrm{SL}_2\\mathbb{C}/\\Gamma$. When the orientifold group contains the element $\\Omega' = \\Omega R_{45}(-1)^{F_L}$, whose fixed locus is an O7-plane, the twist localizes the theory entirely onto that plane, and the bulk is described by unoriented topological strings on $\\mathrm{SL}_2\\mathbb{C}/G_1$; the expected $\\mathrm{SO}(8)$ Kac-Moody subalgebra in the boundary chiral algebra matches the $\\mathrm{SO}(8)$ holomorphic Chern-Simons theory on the space-filling branes. When the orientifold instead contains an O3-plane, the bulk background is the same quotient $\\mathrm{SL}_2\\mathbb{C}/\\Gamma$ as for the orbifold by $\\Gamma$, but the orientation-reversing elements act as a nontrivial $\\mathbb{Z}_2$-bundle over the quotient, equivalently a choice of spin structure, which fixes the boundary conditions for the fermionic Chern-Simons fields $\\alpha$ and $\\gamma$ while leaving the complex-structure sector (the A and D towers of operators) untouched. The explicit $\\mathbb{Z}_2$ example shows that the $\\mathrm{SO}(N)$/$\\mathrm{USp}(2N)$ chiral algebras differ from the two-node quiver theory precisely in the parity of the B and C towers, and the paper conjectures this spin-structure distinction persists for every ADE subgroup of $\\mathrm{SU}(2)$.","pith_inferences":["Beyond the paper's claims, the spin-structure mechanism suggests a general rule: whenever a discrete symmetry with orientation reversal acts on a twisted-holographic background, its only imprint in the protected sector will be through fermionic boundary conditions, making the B and C towers universal detectors of such $\\mathbb{Z}_2$-bundles.","The conjecture could be stress-tested at finite $N$ by computing the characters of the chiral algebras for the binary tetrahedral or octahedral orientifold quivers and comparing with open topological string partition functions on $\\mathrm{SL}_2\\mathbb{C}/\\Gamma$; a mismatch there would show where the extrapolation from the $\\mathbb{Z}_2$ example to the full ADE family fails.","One can also ask whether the O7 localization onto unoriented topological strings admits a direct worldsheet definition as an orientifold of the B-model, in which case the anomaly-cancellation condition for unoriented topological strings would serve as a consistency check for the entire twisted duality.","If the spin structure is visible in the chiral algebra, modular properties or spectral-flow sectors of the two-dimensional theory should detect it, giving a purely field-theoretic invariant that distinguishes orientifold duals on the same Calabi-Yau threefold."],"forward_implications":["The chiral algebra associated to a given orientifold group is independent of the chosen weakly coupled limit, so quivers appearing in the same box of the paper's tables must have identical chiral algebras in the large-$N$ limit, since they describe the same B-model background.","The two-node $\\mathbb{Z}_2$ orbifold theory and the $\\mathrm{SO}(2N+1)$/$\\mathrm{USp}(2N)$ orientifold theories share the same complex-structure sector (the A and D towers) but differ in the fermionic sector (the B and C towers), with the latter two theories identical in the large-$N$ limit as a manifestation of S-duality.","For O7 orientifolds with group $\\mathbb{Z}_2^{\\Omega'}\\times G_1$, the dual is the unoriented topological string on $\\mathrm{SL}_2\\mathbb{C}/G_1$, and the $\\mathrm{SO}(8)$ flavor symmetry of the boundary chiral algebra matches the $\\mathrm{SO}(8)$ holomorphic Chern-Simons theory on the space-filling branes.","The orientifold information that survives the twist is precisely the spin structure, so distinct orientifold theories can share the same Calabi-Yau vacuum but still be distinguished by their fermionic boundary conditions.","The proposal extends the twisted holography dictionary from orbifold theories to the full list of $\\mathcal{N}=2$ superconformal gauge theories coming from O3- and O7-plane orientifolds, including all finite subgroups of $\\mathrm{SU}(2)$ in the ADE classification."],"supporting_citations":[{"why":"Establishes the prototypical twisted holography duality between the chiral algebra of $\\mathcal{N}=4$ super Yang-Mills theory and BCOV theory on $\\mathrm{SL}_2\\mathbb{C}$, the template this paper extends to orientifold groups.","marker":"[10]"},{"why":"Defines the chiral algebra associated to any four-dimensional $\\mathcal{N}=2$ SCFT, the boundary object whose holographic dual the paper proposes.","marker":"[2]"},{"why":"Introduces the notion of twisting supergravity by a bosonic ghost background, the bulk-side counterpart of the $Q+S$ twist.","marker":"[3]"},{"why":"Identifies the spacetime physics of the B-model topological string as Kodaira-Spencer (BCOV) theory, the bulk theory living on $\\mathrm{SL}_2\\mathbb{C}/\\Gamma$.","marker":"[4]"},{"why":"Constructs the unoriented topological string and proves its anomaly cancellation, the bulk theory used for the O7-plane duals.","marker":"[24]"},{"why":"Shows that D-branes at orbifold singularities produce quiver gauge theories, the construction this paper revisits and extends to orientifolds.","marker":"[12]"},{"why":"Supplies the physical holographic dual of the $\\mathrm{SO}(N)$/$\\mathrm{USp}(2N)$ orientifold theories, IIB on $\\mathrm{AdS}_5\\times \\mathbb{RP}^5$, the starting point for the twisted $\\mathbb{Z}_2$ example.","marker":"[32]"},{"why":"Provides the $\\mathrm{AdS}_5\\times S^5/\\mathbb{Z}_k$ holographic dual of orbifold quiver theories, the background whose twisted version is generalized here.","marker":"[31]"}],"fun_headline_variants":["Orientifold twist ties N=2 theories to topological strings on SL2C/Γ","Twist makes N=2 orientifold duality a spin-structure choice","Spin structure decides bulk topological string dual for N=2 orientifolds","O7 and O3 twists map N=2 chiral algebras to topological string duals","Origami twist: N=2 orientifold holography folds to spin structure"],"cache_read_input_tokens":3200,"weakest_assumption_plain":"The load-bearing premise is that, after twisting, the orientation-reversing part of an orientifold only chooses which fields are periodic or antiperiodic around the cycles of $\\mathrm{SL}_2\\mathbb{C}/\\Gamma$ and adds no other new structure to the bulk, a pattern verified only in the two-element example and assumed for the entire ADE family of finite subgroups.","fun_headline_variants_meta":{"raw":{"variants":["Orientifold twist ties N=2 theories to topological strings on SL2C/Γ","Twist makes N=2 orientifold duality a spin-structure choice","Spin structure decides bulk topological string dual for N=2 orientifolds","O7 and O3 twists map N=2 chiral algebras to topological string duals","Origami twist: N=2 orientifold holography folds to spin structure"]},"model":"deepseek-v4-flash","effort":"low","cost_usd":0.001099,"raw_usage":{"total_tokens":4618,"prompt_tokens":1007,"completion_tokens":3611,"prompt_tokens_details":{"cached_tokens":384},"prompt_cache_hit_tokens":384,"prompt_cache_miss_tokens":623,"completion_tokens_details":{"reasoning_tokens":3503}},"tokens_in":623,"tokens_out":3611,"duration_ms":25850,"temperature":1.0,"reasoning_tokens":3503,"cache_read_input_tokens":384,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-08-12T15:25:23.849856+00:00","model_set":{"reader":"deepseek-v4-flash"},"falsifier":"Compute the large-$N$ chiral algebra of a nontrivial ADE orientifold theory, for instance the binary tetrahedral O3 orientifold or the O7 theory with $\\Gamma=\\mathbb{Z}_2^{\\Omega'}\\times\\mathbb{Z}_3$, and compare the B and C operator towers, or the full characters, with the prediction of Kodaira-Spencer theory on $\\mathrm{SL}_2\\mathbb{C}/\\Gamma$ with the claimed spin-structure boundary conditions; a mismatch in parity, multiplicity, or level would settle the proposal against the extrapolation from the $\\mathbb{Z}_2$ case.","supporting_citations":[],"review_version":1}