Disciplines / Research questions

Physics

691 research topics · 2739 questions

CTM inversion relations3 questions
  1. Rigorous derivation of the surface and corner free energies of the anisotropic triangular-lattice Ising model: Baxter's product-form conjectures and the corner-factor gauge ambiguity

  2. Rigorous foundation of the inversion-relation derivation of the bulk, surface and corner free energies of the square-lattice Ising model

  3. Conjectured inversion relations for thermalized interaction-round-a-face lattice models built from rational conformal field theories

Exponential structure of the CTM spectrum3 questions
  1. Algebraic and field-theoretic structure of the corner transfer matrix of the exact continuous matrix product state for the Lieb-Liniger model

  2. Lattice-level foundation and domain of validity of the entanglement-spectrum–corner-Hamiltonian correspondence in open quantum spin chains

  3. Analytic theory of the corner-transfer-matrix eigenvalue spectrum and its curvature-induced regularization at criticality for the Ising model on the hyperbolic plane

CTM operator product representation1 questions
  1. Physical origin of flat corner transfer matrix spectra and the renormalizability–entanglement connection in the 2D kicked quantum Ising Floquet system

CTM star-triangle relation2 questions
  1. Exact spectrum of the Floquet evolution operator of star-triangle-derived integrable quantum circuits (Potts and ZQ\mathbb{Z}_Q circuits)

  2. Regularisation of continuous-spin extended Z-invariance and three-point Lagrangian systems as quasi-classical limits of Yang-Baxter lattice models

CTM and the eight-vertex model3 questions
  1. Rigorous derivation of the corner free energy product formulae for integrable Potts and loop models, and the periodicity structure of their exponents

  2. Rigorous derivation of the electric critical exponents ηe=1−μ/π\eta_e=1-\mu/\pi and δe=(3π+μ)/(π−μ)\delta_e=(3\pi+\mu)/(\pi-\mu) of the symmetric eight-vertex model

  3. Rigorous foundation of the tail-operator construction of form factors in Belavin's (Z/nZ)(\mathbb{Z}/n\mathbb{Z})-symmetric model and the determinant/Riemann–Hilbert structure of eight-vertex form factors

CTM and the density matrix2 questions
  1. A priori characterization of exact entanglement equipartition and reconstruction of the entanglement Hamiltonian from symmetry-resolved entanglement in gapped quantum systems

  2. Microscopic foundation of the entanglement-spectrum-corner-Hamiltonian correspondence in integrable open spin chains

CTM and infinite PEPS contraction1 questions
  1. Conditioning and degeneracy of the environment-differentiation linear systems in CTM-based projected entangled-pair state optimization

CTM and order parameter3 questions
  1. Single-valued hyperelliptic representation of the automorphism-invariant order-parameter combination Lpq(r)L_{pq}(r) of the chiral Potts model for arbitrary rapidities

  2. Pair-correlation functions of the two-dimensional integrable N-state chiral Potts model

  3. Chiral Potts order parameters from finite-lattice determinant representations: homogeneous and thermodynamic limits in general ZpZ_p representations, and one-determinant form factors for the generators vnv_n

CTM and hard-hexagon model1 questions
  1. Foundations of the inversion-relation free energy of thermalized IRF lattice models and the identity of the coset factor G\mathcal{G}

CTMRG3 questions
  1. Kosterlitz–Thouless critical reduced field of the triangular Ising antiferromagnet in a field: controlled finite-bond-dimension extrapolation for C3C_3-symmetric CTMRG and the asymptotics of the three-state Potts critical line

  2. Robust lattice-tailored corner transfer matrix renormalization group for non-positive tensor networks on Archimedean lattices

  3. Symmetry-adapted subspace-iteration CTMRG for two-dimensional tensor networks

density-matrix renormalization group(DMRG)2 questions
  1. A priori prediction of the shared bond dimension of bundled matrix product states for many low-lying excitations

  2. Convergence theory and principled subspace enrichment for one-site DMRG-type alternating optimization in tensor train format with adaptive ranks

diagonal and non-diagonal scattering3 questions
  1. First-principles derivation of the boundary entropy for the current-perturbed SU(2)kSU(2)_k WZNW model: proving the diagonalize-and-normalize g-function procedure in a non-diagonal integrable quantum field theory

  2. Modified crossing in exact S-matrices of 1+1d QFTs with non-invertible symmetries: dynamical verification and completion of the categorical bootstrap

  3. Analytic characterization and field-theory realization of extremal charged S-matrices in 1+1 dimensions

dichromatic polynomial2 questions
  1. Arbitrary-width structure of the Potts partition-function-zero accumulation locus on self-dual square-lattice strips (the Chang–Shrock conjecture)

  2. The generalized Beraha conjecture for non-planar graphs: integer-Q eigenvalue cancellations, limiting curves, and density of flow roots for generalized Petersen graphs

difference property1 questions
  1. Prove or disprove that the boost condition [Q2,Q3]=0[Q_2,Q_3]=0 is equivalent to Yang–Baxter solvability for non-difference-form and non-diagonalizable nearest-neighbour spin chains

    Open for about 31 years
dilogarithm identities2 questions
  1. Removing the full-rank hypothesis from the cluster aa-variable periodicity derivation of higher-degree Rogers dilogarithm identities

  2. Nil-DAHA and quantum dilogarithm derivations of Rogers-Ramanujan type identities: the Cherednik-Feigin quantum lift and dilogarithm identities for untwisted nonsimply-laced affine types

dilogarithm sum rules2 questions
  1. Periodicity, Rogers dilogarithm sum rules and cluster-algebra status of the (N,p) crossed Y-systems from the low-energy AdS4 x CP3 string

  2. Precise generalized Nahm conjecture for half-indices of 3d Chern-Simons matter theories and the dynamical verification of the candidate modular Nahm sums

Mechanism of DNA overstretching deformation3 questions
  1. Quantitative microscopic account of the DNA overstretching transition: coexistence force, S-state structure, and sequence-dependent cooperativity

    Open for about 12 years
  2. Structural organization and melting kinetics of overstretched DNA under defined topological constraint

    Open for about 16 years
  3. Sequence-dependent B-to-S kinetics, the B–S free-energy landscape, and hairpin-trapped reannealing among overstretched DNA structures

    Open for about 11 years
Dolan–Grady relation2 questions
  1. A Lusztig-type quantum group structure for the q-Onsager algebra at roots of unity: presentation, cyclic tridiagonal pairs, and non-abelian symmetry sectors of the open XXZ chain

    Open for about 10 years
  2. Open directions in the charge-pump characterization of SPT phases: pivot loops, the Onsager algebra, representation-SPTs, and equivariant families

    Open for about 1 year
domain-wall boundary condition2 questions
  1. Completing the steepest-descent asymptotics of two-dimensional Ising interface partition functions: wetting-pole residues and uniform ordering of exponentially small corrections

    Open for about 1 year
  2. Arctic curves of the six-vertex model with partial domain-wall, reflecting-end, and half-turn boundary conditions: generic-weight determination and the domain-wall equivalence class

    Open for about 8 years
dressed energy2 questions
  1. Large-time asymptotics and finite-temperature spectral function of a mobile impurity in a one-dimensional gas

  2. Rigorous low-temperature expansions for the thermodynamic nonlinear integral equations of integrable models beyond the Lieb–Liniger gas, and rigorous 1/L finite-size corrections

dressed velocity1 questions
  1. An independent, fully classical derivation of the effective velocity and dressing equations of generalized hydrodynamics for classical integrable field theories with radiative modes (sinh-Gordon prototype)

Drude weight3 questions
  1. Sine-Gordon TBA and generalised hydrodynamics at generic coupling: Y-system equivalence, charge-conjugation-odd conserved quantities, and anomalous topological-charge transport beyond Euler scale

  2. Rigorous foundations of the finite-temperature spin Drude weight of the gapless XXZ chain: charge completeness, incommensurate anisotropies, and the fractal (popcorn) structure

  3. Open spin-transport problems for the integrable arbitrary-spin XXZ chain: low-temperature Drude weight, irrational anisotropy, the isotropic point, and Kohn-formula equivalence

Duality and Star-Triangle Transformations of Planar Ising Models1 questions
  1. The precise relation between Chang duality of the two-dimensional ϕ4\phi^4 theory and the continuum limit of Kramers-Wannier duality

    Open for about 5 years
Entanglement spectrum and CTM spectrum1 questions
  1. Natural momentum labeling of corner-tensor entanglement spectra for infinite two-dimensional quantum systems

entropy production in integrable systems2 questions
  1. Hydrodynamic entropy production versus entanglement growth in a trapped one-dimensional Bose gas thermalising via diffusion

  2. Extensive entropy increase in isolated quantum systems: beyond the eigenstate thermalization hypothesis and beyond instantaneous quenches

Euler-scale transport2 questions
  1. Open problems of ballistic macroscopic fluctuation theory: rigorous foundations, shock selection, subleading corrections, full counting statistics, and the non-integrable, quantum, and experimental frontiers

  2. Well-definedness and shock-limited validity of the nonlinear projection formula for Euler-scale correlation functions

excited-state TBA3 questions
  1. TBA/NLIE equations for monster potentials: the excited-state sector of the ODE/IM correspondence

  2. TBA pseudo-energy reformulation of exact finite-volume expectation values and generalization to integrable quantum field theories with non-diagonal scattering beyond the sine-Gordon model

  3. Excited-state g-functions from analytic continuation of the Tracy-Widom TBA

Face-type Yang–Baxter equation4 questions
  1. Associative Yang-Baxter-type equation for fully dynamical (IRF-type) quantum R-matrices

  2. Classification of integrable interaction-round-a-face models of qubits and of their integrable unitary boundary processes

  3. Multiplicity-generalized conformal-field-theory construction of trigonometric RR-matrices and interaction-round-a-face weights (benchmark: the unrestricted su(3)k\mathfrak{su}(3)_k adjoint face model)

  4. Rigorous proof or refutation of the general-rank basic hypergeometric sum/integral identity and multi-spin IRF Yang-Baxter solution of Gahramanov and Jafarzade

face–vertex correspondence4 questions
  1. Universal vertex-IRF transformation for quantum affine algebras: realizing generalized Belavin-Drinfeld data, extending the Balog-Dabrowski-Feher classification, infinite-dimensional evaluation, and the Whittaker-module link

    Open for about 19 years
  2. Completing the 20-vertex to solid-on-solid correspondence: explicit evaluation of the Boltzmann weight constants

    Open for about 1 year
  3. Exact spectra and elliptic quantum-group structures for the q-deformed Inozemtsev and MZ' long-range spin chains

    Open for about 2 years
  4. Two-sided invertibility of cell maps and connecting-system hypotheses in the groupoid intertwiner-twist construction for the dynamical Yang-Baxter equation

    Open for about 2 years
finite-entanglement scaling2 questions
  1. Rigorous origin of the finite-bond-dimension scaling law ξ(D)∼Dκ\xi(D)\sim D^{\kappa} in tensor network renormalization

  2. Theory of the finite-entanglement perturbation and the encoding of conformal operator content in matrix product state transfer operators

Form factors and correlation function representation2 questions
  1. Consistent form factor programme and physical interpretation of the minimal form factor ambiguity for integrable QFTs deformed by finitely many generalized TTˉT\bar T perturbations

    Open for about 2 years
  2. Convergence of the form-factor expansion of correlation functions in the 1+1-dimensional sinh-Gordon model beyond the space-like vacuum two-point function, and the sharp large-N asymptotics of its summands

    Open for about 6 years
form-factor bootstrap3 questions
  1. Quantum energy inequalities in interacting integrable quantum field theories beyond one-particle level: stress-tensor prefactor freedom, parity breaking, and higher particle numbers

  2. Completing the form-factor bootstrap for TTˉT\bar T-deformed integrable quantum field theories: higher-particle form factors and the fate of the kinematic residue equation

  3. Thermodynamic form factor bootstrap for integrable quantum field theories with bound states and non-diagonal scattering

Fredholm determinant1 questions
  1. Completing the deformed Tracy–Widom theory for Fredholm determinants of Schrödinger-type kernels: general wave functions, multi-interval support, large-gap asymptotics, and the Schlesinger structure

fusion hierarchy2 questions
  1. Closure relations and complete separation-of-variables spectrum characterization for twisted glM∣Ngl_{\mathcal{M}|\mathcal{N}} and Hubbard models

    Open for about 7 years
  2. Trace conjectures and zero-pattern classification for the dilute A2(2)A_2^{(2)} loop model at λ=π/3λ=π/3: the conformal partition functions of critical site percolation on the triangular lattice

    Open for about 3 years
Gaudin determinant1 questions
  1. Rigorous proof of the universal MPS–Bethe-state overlap formula for orthogonal and symplectic rational spin chains

    Open for about 1 year
Gaussian/c=1c=1 critical line2 questions
  1. Stochastic-geometry description of critical Ashkin–Teller interfaces: the boundary-operator map, the four fractal dimensions, SLE4_4 traces, and FK–spin duality in the c=1c=1 extended conformal field theory

  2. Critical behaviour of the ferromagnetic square-lattice Ashkin–Teller model: rigorous verification of the predicted critical exponents and transition order along the transition curves

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