Disciplines / Research questions
Physics
691 research topics · 2739 questions
generalized Gibbs ensemble3 questions
Deep thermalization in interacting integrable quantum systems: constructing the analogue of the deep generalized Gibbs ensemble beyond free fermions
Extending the nonlinear integral equation formulation of the sine-Gordon generalized Gibbs ensemble beyond the individual-boundedness restriction
Determining the number of Lagrange multipliers needed for generalized Gibbs ensemble descriptions of realistic integrable quantum systems
generalized hydrodynamics(GHD)2 questions
Hall–Littlewood and -Whittaker process2 questions
Hard Hexagon and Related Models7 questions
Algorithmic Pirogov–Sinai theory at the phase boundary: efficient counting and sampling in the phase-coexistence regime for lattice models
Open for about 8 yearsPhase diagram of the loop model with large and its hard-hexagon limit
Open for about 11 yearsGlobal analytic structure of the hard-hexagon partition function per site in the complex fugacity plane: dominant eigenvalue branches beyond Baxter's solution
Open for about 13 yearsExact evaluation of the entropy of -colorings of the square lattice (-species close-packed hard-square lattice gas): vertex-model, transfer-matrix, and graph-expansion routes
Open for about 56 yearsControlled determination of the critical parameters of the disordered-columnar transition in the 2x2 hard-square (2-NN exclusion) lattice gas
Open for about 9 yearsHigher-order terms, convergence, and quantitative validity of the high-activity expansion for the hard square lattice gas with nearest- and next-nearest-neighbor exclusion
Open for about 14 yearsCommon crossing of finite-width density curves at the critical point of the hard-square lattice gas
Open for less than 1 year
Hard-hexagon critical activity3 questions
Localized-magnon saturation physics of frustrated antiferromagnets beyond the smallest-area hard-core description: extra ground states, residual entropy, hard-square thermodynamics, and microscopic U and V parameters
Nonunitary string-net PEPS: tube-algebra central idempotents without C*-structure, gapped non-Hermitian parent Hamiltonians, convergent fixed-point algorithms, and extensions to logarithmic CFTs
Limits of the R-matrix analysis of Mayer cluster coefficients: the spectrum-shift regime, reality of the matrix elements, and error-controlled critical activities
Hard-hexagon critical exponent3 questions
Thermodynamic-limit analytic structure of the non-integrable hard-square lattice gas: zero locus, equimodular gaps, the conjectures, and a discriminant criterion for integrability
Critical exponents from Mayer cluster coefficients: completing the R-matrix asymptotic theory beyond its validated range
Analytic structure of the hard-hexagon partition function per site in the complex fugacity plane: dominant transfer-matrix eigenvalue branches, the necklace region and its zeros, and the algebraic origin of the extra eigenvalues
Hard-hexagon model3 questions
Conjectural foundations of the inversion-relation solution for solvable IRF lattice models: thermalization, analyticity of the free energy, and the unidentified coset CFT
Thermodynamic-limit analytic structure of the hard-hexagon partition function at complex fugacity: the necklace of zeros and the transfer-matrix eigenvalue branches beyond Baxter's solution
Exact entanglement characterization of the Rokhsar-Kivelson quantum hard-square lattice gas: Rényi entropies, integrable entanglement spectra, and the extension beyond two-leg ladders
Hard-hexagon order parameter2 questions
Hard-square model4 questions
Melting scenario of the period-3 phase of the hard-square model with diagonal interactions: Lifshitz point location, anisotropic critical exponents, and floating-phase boundaries
Exact values of the hard-square entropy constant and the bipartite hard-square constant for grid-graph independent-set enumeration
Existence, sharpness, and location of the uniqueness threshold of the hard-core lattice gas on the square lattice (conjectured )
Unresolved phase diagram, Gibbs-measure classification, and sharp correlation decay for the hard-square lattice gas
Hecke algebra1 questions
height function3 questions
Asymptotic variance constant and Gaussian scaling limits for the square-ice height function and generalized solid-on-solid models
Disorder-induced regions and the height-function scaling limit in the square-lattice dimer model with layered quenched disorder
Uniqueness of limit shapes for the six-vertex model with rare corners and restricted Mallows permutations at general bias
higher-order TRG3 questions
Systematically improvable three-dimensional tensor-network renormalization group: controlled entanglement filtering of the area-law obstruction and extraction of universal data in 3D lattice models
Grassmann tensor-network coarse-graining for four-dimensional lattice QCD: full gauge-fermion treatment with controlled truncation accuracy
Provable error bounds for randomized higher-order tensor renormalization group methods (R-HOTRG, MDTRG, Triad-MDTRG)
Ice-Type Models4 questions
Residual entropy of ordinary ice: the exact ice-rule configuration count and a precision experimental test of Pauling's estimate
Open for about 90 yearsContinuum limit of the Feynman checkerboard model as a complex-weight six-vertex model in an absorbing strip
Open for about 2 yearsApproximation complexity of the six-vertex model in the white region and on planar graphs
Open for about 8 yearsExact growth constant for colourings of the square lattice with more than three colours
Open for about 49 years
impurity models1 questions
infinite PEPS3 questions
Parent Hamiltonian and Gossamer-Tail Control for Chiral Projected Entangled-Pair States: Bulk Gaps of the Z3 Kitaev Chiral Spin Liquid
Certified extraction of anyon sectors and modular data from infinite PEPS: completeness of transfer-matrix fixed points and correlation-length scaling
Decidability of normalizability, symmetry classification, canonical forms, and the parent-Hamiltonian spectral gap within physically relevant subclasses of projected entangled pair states
interacting particle systems1 questions
intertwiner3 questions
The periodic-diffeomorphism case of the intertwiner volume conjecture for the Kauffman bracket skein algebra
Open for about 3 yearsCompleting the theory of vertical (particle-number-changing) intertwiners in the rational Calogero model
Open for about 1 yearCompleting the permutation-coefficient theory of gl(n) Yangian intertwiners: general parameter permutations, general rank and evaluation order, contour dependence, and factorization equivalence
Open for about 1 year
IRF/face model2 questions
Ising Model on the Bethe Lattice5 questions
Extremality of the Disordered Phase of the Ising Model with Competing Interactions on a Cayley Tree
Open for about 9 yearsAnalytic classification of the invariant sets, positive fixed points, and higher-period orbits of the recursion operator for the Ising model with competing binary and ternary interactions on a third-order Cayley tree
Open for about 5 yearsExactness of closed-form self-consistent equations for the bond-diluted Ising model on the Bethe lattice
Open for about 12 yearsExact solution of the quenched bond-diluted Ising model on the Bethe lattice at finite coupling (, )
Open for about 12 yearsValidity and explanatory power of the finite-variable reduced dynamics for Glauber dynamics of the bond-diluted Ising model on a Bethe lattice
Open for about 16 years
Ising–dimer mapping3 questions
Explicit identification of the local and Fourier inverse Kasteleyn matrices for the critical Z-invariant Ising model on periodic isoradial graphs
Open for about 17 yearsCompleting exact bosonization of the critical Ising model in bounded domains: flat-boundary dimer observables, the half-integer electric endpoint, and lattice-to-continuum constants
Open for about 14 yearsA general structural theory for dimer models on non-bipartite periodic graphs: weak limits of Boltzmann measures and spectral curves
Open for about 17 years
Ising/free-fermion special case1 questions
Izergin–Korepin determinant4 questions
Basis-parametrized determinant representations for the six-vertex model with partial domain wall boundary conditions
Open for about 3 yearsExtending the modified-operator linear-system method for six-vertex partition functions to reflecting boundaries, the trigonometric antiperiodic case, and higher rank
Open for about 2 yearsThe Izergin–Korepin nineteen-vertex domain wall partition function beyond the root of unity: closed forms, reflection boundaries, eigenvector components, and structural characterization
Open for about 11 yearsSix-vertex domain-wall partition function at roots of unity beyond the third: functional-equation evaluation
Jacobi elliptic functions1 questions
Kagomé eight-vertex model1 questions
Kagomé lattice Ising-type model2 questions
Microscopic origin of the anomalous critical scattering at the kagome-ice plateau termination in Ho2Ti2O7 under a tilted [111] field
Open for about 19 yearsExact finite-temperature characterization of the disordered regions of the generalized kagomé-lattice Ising model with pair and triplet interactions
Open for about 7 years
Kagomé Lattice Eight-Vertex Model2 questions
Open problems for the free-fermion eight-vertex models on the square lattice: singularities of staggered free-fermion models, invariant variables, and the general even–odd finite-torus mapping
Open for about 9 yearsUniversality classes of the non-Ising transitions in the six-vertex model on the kagome lattice
Open for about 1 year
Kagomé–square lattice model transformation3 questions
Exact or provably controlled quantum decoration transformations for non-commuting quantum spin lattice models
Open for about 10 yearsExplicit Kagome-type decorated-lattice construction from the gauge/YBE decoration transformation and its place in the integrability web
Open for about 2 yearsYang-Baxter integrability of the 3D quantum crystal melting Hamiltonian: Kagome-lattice Boltzmann weights, a commuting transfer matrix, and the mass-gap conjecture
Kasteleyn orientation2 questions
The Pfaffian recognition problem beyond planar, bipartite, and near-bipartite graphs (Problem 42 of Kothari–de Carvalho–Lucchesi–Little)
Open for about 8 yearsExtending the Pfaffian Sign Theorem for the dimer model to other lattices on the torus and to higher-genus and non-orientable surfaces
Open for about 8 years
KPZ universality class3 questions
Boundaries of Kardar-Parisi-Zhang universality for the chronon in time-crystalline matter
Simultaneous Hausdorff dimension of the geodesic splitting sets in the directed landscape across all time levels
Exact solvability, stationary structure, and KPZ universality of the quantum ASEP and its quantum Kardar-Parisi-Zhang dynamics
Kramers–Wannier duality4 questions
Sector dependence of the exact Kramers–Wannier duality in exactly solvable SO() spin chains: the Ramond sector and its Spin() duality-defect interpretation
Open for about 3 yearsGeneralizing non-invertible Kramers-Wannier and Kennedy-Tasaki transformations beyond one dimension: higher-form gauging, SSPT classification beyond two dimensions, the fermionic exchange origin, and non-invertible Lieb-Schultz-Mattis constraints
Open for about 2 yearsSelf-dual Kramers-Wannier points as non-invertible symmetries: phase transitions and criticality of LDPC codes in non-Euclidean geometries
Open for about 2 yearsThe precise map between Chang/Magruder self-duality of continuum phi^4 theory and Kramers-Wannier / Ising-Z2-gauge lattice duality
Open for about 5 years
Landen transformation3 questions
Selected parameter values of the one-parameter series solutions of the modular Schwarzian equation: algebraicity, D-finiteness, D-D-finiteness, and the diagonals of rational functions
Ordering-independent period matrix of the Case (b) separable N=2 sine-Gordon breather
Does parameter-space modular invariance organize gapped integrable models? Virasoro characters, dualities, and the complex-argument extension of the XYZ chain
Lee–Yang model2 questions
limit shape3 questions
Zero-temperature crystallization of the doubly periodic Aztec diamond dimer model beyond smooth tropical curves and iterated limits
Arctic-circle behavior and domino shuffling for random perfect matchings of Aztec castles (Problem 5.2 of Leoni–Musiker–Neel–Turner)
Smoothness of multinomial dimer limit shapes in dimensions (Kenyon-Wolfram, Question 10.2)
Loop model and conformal field theory1 questions
Has Lorentz symmetry been broken?5 questions
Rigorous indirect bounds on quark-sector CPT violation from the neutral-kaon mass difference
Open for about 17 yearsCoupling of nonlinear electrodynamics to Lorentz-symmetry violation: the electric-background sector, non-CFJ operators, and detectability of the nonlinear-LSV interference terms
Open for about 4 yearsViability and phenomenological consistency of opposite d/s CPT phases as a CPT-violation mechanism in the Standard Model
Open for about 6 yearsSpontaneous Lorentz breaking by Faddeev–Popov ghost condensation in perturbative quantum gravity: the curved-background generalization
Open for about 15 yearsIs foliation-induced Lorentz-symmetry breaking in quantum gravity a relevant perturbation beyond leading order?
Open for about 7 years
Macdonald processes3 questions
Fredholm determinantal representations and asymptotics of periodic Macdonald processes at positive charge
Positivity, canonical mixing decompositions, and rigorous Whittaker scaling limits in the classification of nearest-neighbor Markov dynamics on Macdonald processes
Multipoint scaling limits, Pfaffian structure, and the Whittaker degeneration chain for half-space Macdonald processes