{"id":"20bfa7c4-1740-4d1f-ac86-af95f3ee2fa6","arxiv_id":"2607.12410","paper_version":1,"verdict":"UNVERDICTED","confidence":"LOW","novelty_score":6.0,"correctness_risk":"high","formal_verification":"none","parameter_count":2,"one_line_summary":"A ghost-Gutzwiller Ansatz on the t-J model yields low-doping FL*, a d-wave superconducting dome, and an overdoped Fermi liquid, reproducing key cuprate phase-diagram features.","lead":"A ghost-Gutzwiller variational wavefunction, optimized at mean-field cost, produces a fractionalized Fermi liquid (FL*) in the single-band t-J model. The resulting doping-temperature diagram also shows a d-wave superconducting dome and an overdoped conventional Fermi liquid, matching key qualitative cuprate features.","discovery_kind":"extension","skeptic_critique":{"model":"grok-4.5","headline":"FL* may be forced by the ghost fractionalization channels of the Ansatz rather than emerging from the t-J model itself.","rationale":"The reader’s weakest_assumption is precisely the load-bearing concern: whether the ghost-Gutzwiller Ansatz faithfully captures t-J physics or injects FL*-like features by construction. Abstract-only access prevents checking the explicit form of the ghost channels, the mean-field equations, Luttinger diagnostics, or any benchmarks against DMRG/VMC, so no stronger or weaker objection can be substantiated. The concern therefore leaves the existing UNVERDICTED verdict and LOW confidence unchanged; the proposed concrete test is the minimal numerical check that would decide whether the emergence claim survives.","tokens_in":1888,"tokens_out":512,"duration_ms":10878,"concrete_test":"At fixed low doping (e.g., x=0.05–0.10) and J/t typical of cuprates, extract the Fermi-surface volume (Luttinger count) from the optimized ghost-Gutzwiller state and recompute the same observable with a ghost-free variational Monte Carlo or DMRG ground state of the identical t-J Hamiltonian on the same lattice; if the volume violation disappears or shrinks below the ghost-Gutzwiller value by a statistically significant margin, the FL* is an Ansatz artifact.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central claim is that an FL* phase emerges in the single-band t-J model via a mean-field-optimized ghost-Gutzwiller Ansatz, yielding a cuprate-like T–doping diagram. For emergence to be a property of the t-J model (rather than of the variational manifold), the ghost channels must not force fractionalization by construction. Ghost-Gutzwiller constructions introduce auxiliary degrees of freedom that fractionalize charge/spin; if the optimized Ansatz lives in a sector that already violates Luttinger’s theorem by design, the reported FL* and the low-doping portion of the phase diagram are artifacts of the trial state, not evidence about the true low-energy physics. The abstract treats the Ansatz as sufficient to generate the full diagram; without an explicit demonstration that FL* survives when the ghost channels are constrained or removed, or that the same diagnostics appear in unbiased methods, the emergence claim rests on an untested fidelity assumption about the Ansatz.","agreement_with_reader":"agree"},"referee_report":{"model":"grok-4.5","summary":"The manuscript claims that a fractionalized Fermi liquid (FL*) phase emerges in the single-band t-J model from a mean-field-optimized ghost-Gutzwiller variational Ansatz. The resulting temperature-doping phase diagram is reported to contain a low-doping FL* region, a d-wave superconducting dome, and an overdoped conventional Fermi liquid, thereby reproducing key qualitative features of cuprate phenomenology. Because only the abstract is available, the explicit form of the Ansatz, the optimization procedure, the Luttinger-volume diagnostics, energy comparisons, and any benchmarks against exact or high-accuracy t-J results cannot be inspected.","tokens_in":2187,"tokens_out":747,"duration_ms":5962,"significance":"If the central claim is substantiated, the work would supply a computationally inexpensive variational route to FL* physics inside the single-band t-J model and a compact cuprate-like T-doping diagram. That would be of clear interest to the strongly correlated community, provided the FL* is shown to be a genuine property of the t-J low-energy physics rather than an artifact of the ghost channels. The abstract advertises a simple mean-field cost and a parameter-light construction; those practical strengths would be valuable if the fidelity of the Ansatz is established.","major_comments":[{"comment":"Only the abstract is available for review. The load-bearing claim that FL* 'emerges' in the t-J model therefore cannot be verified: the explicit ghost-Gutzwiller wavefunction, the mean-field free-energy functional, the Luttinger-volume diagnostic, the energy comparisons that place FL* below competing states, and any checks against exact diagonalization or high-accuracy t-J benchmarks are all inaccessible. Without those elements the emergence claim cannot be assessed.","section":null},{"comment":"The abstract's emergence language is in tension with the structure of ghost-Gutzwiller constructions. Ghost fractionalization channels introduce auxiliary degrees of freedom that can violate Luttinger's theorem by design. For the reported low-doping FL* to be attributed to the t-J model rather than to the variational manifold, the manuscript must demonstrate that FL* survives when the ghost channels are constrained or removed, or that the same diagnostics appear in unbiased methods. No such control is described in the abstract; this is the central fidelity assumption that must be tested before the phase diagram can be read as a property of the t-J model.","section":null},{"comment":"Mean-field variational treatments of the t-J model are known to over-stabilize ordered or fractionalized phases. The abstract asserts a full temperature-doping diagram (FL*, d-wave dome, overdoped FL) obtained at mean-field cost. Without finite-size scaling, comparison to known t-J ground-state energies, or an assessment of the variational bias, it is unclear whether the reported sequence of phases is robust or an artifact of the mean-field approximation.","section":null}],"minor_comments":[],"recommendation":"uncertain","confidential_remarks":"This is an abstract-only review (full text unavailable). The recommendation is therefore uncertain by necessity: the technical content required to evaluate the load-bearing claims is missing. If the full manuscript is supplied, the report should be reopened; the two central issues to check first are (i) whether the ghost channels force FL* by construction and (ii) whether the variational energies and Luttinger diagnostics are benchmarked against unbiased t-J data. Scope appears appropriate for a condensed-matter theory journal once those points are resolved."},"author_rebuttal":null,"desk_editor":{"model":"grok-4.5","letter":"The one thing to know: this abstract claims that a simple ghost-Gutzwiller Ansatz, optimized at mean-field cost, produces an FL* phase inside the single-band t-J model and a T–doping diagram with low-doping FL*, a d-wave SC dome, and overdoped FL. That combination, if it holds up in the full paper, is a useful technique-level result for cuprate/pseudogap work. It is not a first-principles proof that FL* is the true t-J ground state.\n\nWhat looks new is the packaging: ghost channels plus Gutzwiller projection, cheap enough to scan temperature and doping, and reported to land on the qualitative cuprate sequence. Gutzwiller and slave-particle treatments of t-J, and FL* as a pseudogap candidate, are established; the contribution is that this particular variational route is claimed to deliver the whole diagram without heavy numerics. Credit that if the full text shows clean diagnostics (Luttinger volume, energy comparisons, phase boundaries) and honest comparison to known t-J benchmarks.\n\nThe soft spot is real and load-bearing for the “emerges in the t-J model” language. Ghost fractionalization channels can put FL*-like states inside the variational manifold by construction. Without the paper showing that FL* survives when those channels are constrained or removed, or that the same signatures appear in unbiased methods, the low-doping FL* may be an artifact of the trial state rather than a property of the Hamiltonian. Mean-field variational treatments of t-J are known to over-stabilize ordered or fractionalized phases; that is a standard caveat, not a manufactured one. Free parameters (J/t, longer-range hoppings, ghost hybridizations) will also matter for how much of the diagram is robust.\n\nWe only have the abstract, so derivation, diagnostics, and benchmarks cannot be inspected. The stress-test concern about forced fractionalization is the right one to carry into the full text; it may or may not land once the math is visible.\n\nWho it is for: people who already work on variational/slave-particle approaches to doped Mott systems and want a cheap FL* route for phase-diagram scans. Not for someone looking for a definitive resolution of the t-J ground state. It deserves a serious referee if the full paper ships the Ansatz details, Luttinger diagnostics, and energy comparisons; desk-reject only if those are missing. I would not cite from the abstract alone, and I would not put it in reading group until the full text is out. Send to peer review when the manuscript is complete—the claim is important enough inside the field to warrant referee time, even if revision will demand tighter controls on the ghost sector.","headline":"Abstract-only claim of FL* from ghost-Gutzwiller on t-J; technique-level interest, but emergence vs. Ansatz artifact cannot be checked yet.","tokens_in":2768,"tokens_out":667,"would_cite":false,"duration_ms":5444,"reading_group":"no","serious_thinker":"unclear","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"grok-4.5","headline":"A simple ghost-Gutzwiller Ansatz yields a fractionalized Fermi liquid phase and a cuprate-like diagram in the single-band t-J model.","keywords":["fractionalized Fermi liquid","FL*","ghost-Gutzwiller Ansatz","t-J model","cuprates","pseudogap","d-wave superconductivity","Luttinger's theorem"],"falsifier":"A controlled numerical benchmark (exact diagonalization on small clusters or high-accuracy DMRG/ variational Monte Carlo without ghost channels) showing that the t-J ground state at low doping remains a conventional Fermi liquid or lacks the FL* signatures predicted by the optimized ghost-Gutzwiller Ansatz.","tokens_in":2810,"feed_emoji":"⚡","tokens_out":600,"duration_ms":4656,"temperature":0.7,"pith_summary":"This paper claims that a fractionalized Fermi liquid (FL*) phase arises naturally in the single-band t-J model when the ground state is approximated by a ghost-Gutzwiller variational Ansatz that can be optimized at mean-field cost. FL* metals combine fractionalized quasiparticles with ordinary ones and violate Luttinger's theorem; they have long been proposed as candidates for the pseudogap of underdoped cuprates. The authors report that the optimized Ansatz produces a temperature-doping phase diagram containing a low-doping FL* region, a d-wave superconducting dome, and an overdoped conventional Fermi liquid, thereby recovering the main qualitative features of cuprate phenomenology from a single, inexpensive variational calculation. If correct, the result shows that the essential physics of fractionalization and the cuprate diagram can be captured without heavy numerical machinery once the right fractionalization channels are built into the trial wave function.","feed_headline":"Ghost-Gutzwiller Ansatz yields FL* and cuprate-like diagram","feed_subtitle":"Mean-field optimization of a simple trial state recovers FL*, d-wave dome, and overdoped Fermi liquid in the t-J model.","key_machinery":"The ghost-Gutzwiller Ansatz: a variational wave function that introduces auxiliary \"ghost\" fractionalization channels inside a Gutzwiller projected state, allowing simultaneous treatment of conventional and fractionalized quasiparticles and optimized by a mean-field calculation.","core_discovery":"A FL* phase emerges in the single-band t-J model through a simple ghost-Gutzwiller Ansatz optimized at mean-field cost. The resulting temperature-doping phase diagram encompasses a low-doping FL*, a d-wave superconducting dome, and an overdoped conventional Fermi liquid, reproducing key qualitative features of cuprate phenomenology.","pith_inferences":[],"forward_implications":[],"fun_headline_variants":["Ghost-Gutzwiller Ansatz produces FL* in t-J model","FL* emerges via simple ghost-Gutzwiller in t-J","Mean-field ghost Ansatz yields cuprate-like FL* diagram","t-J model hosts FL*, d-wave dome via ghost-Gutzwiller","Simple ghost-Gutzwiller recovers FL* and cuprate features"],"cache_read_input_tokens":2304,"weakest_assumption_plain":"That the ghost-Gutzwiller channels, once mean-field optimized, faithfully capture the true low-energy physics of the t-J model rather than forcing FL*-like features by construction of the trial state.","fun_headline_variants_meta":{"raw":{"variants":["Ghost-Gutzwiller Ansatz produces FL* in t-J model","FL* emerges via simple ghost-Gutzwiller in t-J","Mean-field ghost Ansatz yields cuprate-like FL* diagram","t-J model hosts FL*, d-wave dome via ghost-Gutzwiller","Simple ghost-Gutzwiller recovers FL* and cuprate features"]},"model":"grok-4.5","effort":"low","cost_usd":0.00174,"raw_usage":{"total_tokens":768,"prompt_tokens":669,"num_sources_used":0,"completion_tokens":99,"cost_in_usd_ticks":17400000,"prompt_tokens_details":{"text_tokens":669,"audio_tokens":0,"image_tokens":0,"cached_tokens":128},"completion_tokens_details":{"audio_tokens":0,"reasoning_tokens":0,"accepted_prediction_tokens":0,"rejected_prediction_tokens":0}},"tokens_in":669,"tokens_out":99,"duration_ms":1052,"temperature":1.0,"reasoning_tokens":0,"cache_read_input_tokens":128,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-07-15T06:18:37.800922+00:00","model_set":{"reader":"grok-4.5"},"falsifier":"A controlled numerical benchmark (exact diagonalization on small clusters or high-accuracy DMRG/ variational Monte Carlo without ghost channels) showing that the t-J ground state at low doping remains a conventional Fermi liquid or lacks the FL* signatures predicted by the optimized ghost-Gutzwiller Ansatz.","supporting_citations":[],"review_version":1}