Scientists / Open questions

Steven Weinberg

Particle physics; quantum field theory; cosmology

1979 Nobel Prize in Physics

27 questions

Realistic radiative generation of first- and second-generation fermion masses: the completion problem of Weinberg's third-generation-only framework
Ab initio Standard-Model prediction of $\eta\to 3\pi$ decay and the correction $\Delta Q$ to the chiral low-energy theorem for the quark-mass ratio $Q$
Dynamical justification of the tree-approximation chiral-Lagrangian eikonal treatment of semisoft and virtual pions in high-energy hadron reactions (Weinberg's summing-soft-pions framework)
Dynamical Kaluza–Klein compactification: stabilizing the extra dimensions and deriving the observed gauge couplings without fine-tuning
Weinberg's 1959 0⁺→0⁺ muon-capture/electron-scattering ratio test of the vector weak current and the identification of additional suitable nuclear levels
Nonperturbative determination of the vacuum pion-field distribution underlying soft-pion unitarity damping in hard-hadron reactions
Genuine few-nucleon contributions to low-energy pion–nucleus scattering beyond the deuteron in chiral effective field theory
Convergent perturbation theory for Coulomb scattering and charged few-body systems: the uncompleted core of Weinberg's 1963 quasiparticle program
Rigorous foundation of Weinberg's tree theorem for the in-in formalism: the classical double-trajectory prescription for tree-level correlations
Discrete symmetries and non-Lorentzian tangent-space groups: the open directions of Weinberg's causality-based spin-statistics program in higher spacetime dimensions
Foundations of the infinite-momentum (light-front) formulation of quantum field theory: zero-mode renormalization, equivalence with covariant quantization, and Lorentz covariance under Fock-space truncation
Open issues in Weinberg's chiral effective field theory of nuclear forces: power-counting/renormalization consistency, the fine-tuned s-wave contact term, and multi-nucleon forces
Baryon-tower mass splittings from non-tower pion transitions in current-algebra sum rules
Completing Weinberg's ordinary-energy supersymmetry program: natural Fayet-Iliopoulos terms, anomaly-free U(1) spectra, vacuum stability, and dimension-six proton decay
All-orders consistency of the SO(8192) unoriented open bosonic string: higher-loop dilaton-tadpole cancellation, the closed-string-tachyon regulator, and the origin of the special Chan–Paton choice
A natural theory of fermion masses and flavor mixing: the open problem of Weinberg's 1977 lecture "The Problem of Mass"
Compositeness beyond the weak-binding regime: the surviving open core of Weinberg's 1963 elementary-particle theory of composite particles
Characterizing the multi-field inflationary potentials for which the curvature perturbation $\mathcal{R}$ approaches a constant as the universe expands
Attractivity, collisionless anisotropic inertia, and quantum-loop stability of adiabatic superhorizon solutions: the open core of Weinberg's general-case program
Diffraction corrections and unexecuted amplitude integrals in the eikonal method for magnetohydrodynamic waves (Weinberg, 1962)
Naturalness of the two-nucleon system in QCD: why the S-wave contact interactions sit near the unitarity (4π) fixed point and the deuteron is bound by only 2.2 MeV
Exact spectral-function sum rules beyond asymptotic freedom: the domain of validity of the Bernard-Duncan-LoSecco-Weinberg relations
Completing Weinberg's 1964 connected-kernel program for multiparticle scattering: relativistic antiparticle extension, many-body limit, sharp kernel conditions, and practical computability
Dynamical QCD origin of the constituent quark's Dirac-like electroweak couplings: the $g_A=+1$ selection and the vanishing anomalous magnetic moment (Weinberg, 1990)

Back to open problems

Realistic radiative generation of first- and second-generation fermion masses: the completion problem of Weinberg's third-generation-only framework

Ab initio Standard-Model prediction of η→3π\eta\to 3\piη→3π decay and the correction ΔQ\Delta QΔQ to the chiral low-energy theorem for the quark-mass ratio QQQ

Dynamical justification of the tree-approximation chiral-Lagrangian eikonal treatment of semisoft and virtual pions in high-energy hadron reactions (Weinberg's summing-soft-pions framework)

Dynamical Kaluza–Klein compactification: stabilizing the extra dimensions and deriving the observed gauge couplings without fine-tuning

Weinberg's 1959 0⁺→0⁺ muon-capture/electron-scattering ratio test of the vector weak current and the identification of additional suitable nuclear levels

Nonperturbative determination of the vacuum pion-field distribution underlying soft-pion unitarity damping in hard-hadron reactions

Genuine few-nucleon contributions to low-energy pion–nucleus scattering beyond the deuteron in chiral effective field theory

Convergent perturbation theory for Coulomb scattering and charged few-body systems: the uncompleted core of Weinberg's 1963 quasiparticle program

Rigorous foundation of Weinberg's tree theorem for the in-in formalism: the classical double-trajectory prescription for tree-level correlations

Discrete symmetries and non-Lorentzian tangent-space groups: the open directions of Weinberg's causality-based spin-statistics program in higher spacetime dimensions

Foundations of the infinite-momentum (light-front) formulation of quantum field theory: zero-mode renormalization, equivalence with covariant quantization, and Lorentz covariance under Fock-space truncation

Open issues in Weinberg's chiral effective field theory of nuclear forces: power-counting/renormalization consistency, the fine-tuned s-wave contact term, and multi-nucleon forces

Baryon-tower mass splittings from non-tower pion transitions in current-algebra sum rules

Completing Weinberg's ordinary-energy supersymmetry program: natural Fayet-Iliopoulos terms, anomaly-free U(1) spectra, vacuum stability, and dimension-six proton decay

All-orders consistency of the SO(8192) unoriented open bosonic string: higher-loop dilaton-tadpole cancellation, the closed-string-tachyon regulator, and the origin of the special Chan–Paton choice

A natural theory of fermion masses and flavor mixing: the open problem of Weinberg's 1977 lecture "The Problem of Mass"

Compositeness beyond the weak-binding regime: the surviving open core of Weinberg's 1963 elementary-particle theory of composite particles

Characterizing the multi-field inflationary potentials for which the curvature perturbation R\mathcal{R}R approaches a constant as the universe expands

Attractivity, collisionless anisotropic inertia, and quantum-loop stability of adiabatic superhorizon solutions: the open core of Weinberg's general-case program

Diffraction corrections and unexecuted amplitude integrals in the eikonal method for magnetohydrodynamic waves (Weinberg, 1962)

Naturalness of the two-nucleon system in QCD: why the S-wave contact interactions sit near the unitarity (4π) fixed point and the deuteron is bound by only 2.2 MeV

Exact spectral-function sum rules beyond asymptotic freedom: the domain of validity of the Bernard-Duncan-LoSecco-Weinberg relations

Completing Weinberg's 1964 connected-kernel program for multiparticle scattering: relativistic antiparticle extension, many-body limit, sharp kernel conditions, and practical computability

Dynamical QCD origin of the constituent quark's Dirac-like electroweak couplings: the gA=+1g_A=+1gA​=+1 selection and the vanishing anomalous magnetic moment (Weinberg, 1990)

Ab initio Standard-Model prediction of $\eta\to 3\pi$ decay and the correction $\Delta Q$ to the chiral low-energy theorem for the quark-mass ratio $Q$

Characterizing the multi-field inflationary potentials for which the curvature perturbation $\mathcal{R}$ approaches a constant as the universe expands

Dynamical QCD origin of the constituent quark's Dirac-like electroweak couplings: the $g_A=+1$ selection and the vanishing anomalous magnetic moment (Weinberg, 1990)