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Scale invariance vs conformal invariance

12 Pith papers cite this work. Polarity classification is still indexing.

12 Pith papers citing it
abstract

In this review article, we discuss the distinction and possible equivalence between scale invariance and conformal invariance in relativistic quantum field theories. Under some technical assumptions, we can prove that scale invariant quantum field theories in $d=2$ dimension necessarily possess the enhanced conformal symmetry. The use of the conformal symmetry is well appreciated in the literature, but the fact that all the scale invariant phenomena in $d=2$ dimension enjoy the conformal property relies on the deep structure of the renormalization group. The outstanding question is whether this feature is specific to $d=2$ dimension or it holds in higher dimensions, too. As of January 2014, our consensus is that there is no known example of scale invariant but non-conformal field theories in $d=4$ dimension under the assumptions of (1) unitarity, (2) Poincar\'e invariance (causality), (3) discrete spectrum in scaling dimension, (4) existence of scale current and (5) unbroken scale invariance in the vacuum. We have a perturbative proof of the enhancement of conformal invariance from scale invariance based on the higher dimensional analogue of Zamolodchikov's $c$-theorem, but the non-perturbative proof is yet to come. As a reference we have tried to collect as many interesting examples of scale invariance in relativistic quantum field theories as possible in this article. We give a complementary holographic argument based on the energy-condition of the gravitational system and the space-time diffeomorphism in order to support the claim of the symmetry enhancement. We believe that the possible enhancement of conformal invariance from scale invariance reveals the sublime nature of the renormalization group and space-time with holography.

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2026 11 2024 1

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representative citing papers

Cohomological beta function

math-ph · 2026-06-27 · accept · novelty 7.0 · 2 refs

The leading Cardy beta-function coefficient for J¯J deformations of 2D CFTs is the class of a Chevalley-Eilenberg 2-cocycle obstructing deformation of the Virasoro module.

Universal Description of Decoherence in Scale-Invariant Environments

hep-ph · 2026-04-16 · unverdicted · novelty 7.0

Decoherence in scale-invariant environments is uniquely equivalent to an unparticle bath characterized by scaling dimension d_U, which fixes all exponents via consistency relations and predicts a coherence-protection transition at d_U = 5/2.

The state/defect correspondence

hep-th · 2026-06-10 · unverdicted · novelty 6.0

Establishes a one-to-one correspondence between states and p-dimensional defects in higher-form Maxwell theories via an extended Kac-Moody algebra generated by conserved charges from mixed anomalies, mapping dressed Wilson-'t Hooft defects to squeezed energy eigenstates.

Scale-Invariant Open Quantum Systems

hep-ph · 2026-05-21 · unverdicted · novelty 6.0

Scale-invariant open quantum systems are universally described by unparticle baths with scaling dimension d_U, producing non-Markovian kernels, a fractional Caldeira-Leggett master equation, and phase transitions at d_U = 3/2, 2, and 5/2.

Does hot QCD have a conformal manifold in the chiral limit?

hep-th · 2026-03-10 · unverdicted · novelty 6.0

An 't Hooft anomaly at general imaginary baryon chemical potential constrains the QCD chiral transition to three minimal CFT scenarios, with the favored one for N_f >= 3 featuring a conformal manifold of theta_B-dependent universality classes with an exactly marginal operator tied to baryon density.

citing papers explorer

Showing 12 of 12 citing papers.

  • Cohomological beta function math-ph · 2026-06-27 · accept · none · ref 7 · 2 links · internal anchor

    The leading Cardy beta-function coefficient for J¯J deformations of 2D CFTs is the class of a Chevalley-Eilenberg 2-cocycle obstructing deformation of the Virasoro module.

  • The scheme independent 3-sphere free energy is not a monotone F-function hep-th · 2026-03-10 · unverdicted · none · ref 7 · internal anchor

    The scheme-independent 3-sphere free energy decreases at O(g^2) under relevant deformations of a 3D CFT but is not monotone along the full RG flow of the free massive scalar on S^3.

  • Non-Hermitian free-fermion critical systems and logarithmic conformal field theory cond-mat.str-el · 2026-02-02 · unverdicted · none · ref 43 · internal anchor

    A PT-symmetric non-Hermitian free-fermion field theory realizes logarithmic conformal field theory with central charge c=-2 via a biorthogonal Virasoro algebra construction.

  • Gravitational wave constraints on the Paneitz operator gr-qc · 2026-04-30 · unverdicted · none · ref 17

    The Paneitz operator in 4D belongs to extended mimetic gravity and is constrained by gravitational wave propagation speed.

  • Universal Description of Decoherence in Scale-Invariant Environments hep-ph · 2026-04-16 · unverdicted · none · ref 5

    Decoherence in scale-invariant environments is uniquely equivalent to an unparticle bath characterized by scaling dimension d_U, which fixes all exponents via consistency relations and predicts a coherence-protection transition at d_U = 5/2.

  • The state/defect correspondence hep-th · 2026-06-10 · unverdicted · none · ref 73 · internal anchor

    Establishes a one-to-one correspondence between states and p-dimensional defects in higher-form Maxwell theories via an extended Kac-Moody algebra generated by conserved charges from mixed anomalies, mapping dressed Wilson-'t Hooft defects to squeezed energy eigenstates.

  • Scale-Invariant Open Quantum Systems hep-ph · 2026-05-21 · unverdicted · none · ref 18 · internal anchor

    Scale-invariant open quantum systems are universally described by unparticle baths with scaling dimension d_U, producing non-Markovian kernels, a fractional Caldeira-Leggett master equation, and phase transitions at d_U = 3/2, 2, and 5/2.

  • Direct Experimental Test of Conformal Invariance via Grazing Scattering: A Proposal for X-ray and Neutron Experiments cond-mat.stat-mech · 2026-05-07 · unverdicted · none · ref 9 · internal anchor

    Proposal for an experimental test of conformal invariance in critical phenomena via grazing-incidence scattering that checks a momentum-space differential constraint on the cross-section.

  • Does hot QCD have a conformal manifold in the chiral limit? hep-th · 2026-03-10 · unverdicted · none · ref 54 · internal anchor

    An 't Hooft anomaly at general imaginary baryon chemical potential constrains the QCD chiral transition to three minimal CFT scenarios, with the favored one for N_f >= 3 featuring a conformal manifold of theta_B-dependent universality classes with an exactly marginal operator tied to baryon density.

  • Nonadditivity in Quantum Field Theory: Replica Energies, Scaling Filters, and the Renormalization Group hep-th · 2026-06-10 · conditional · none · ref 62 · internal anchor

    The replica-energy filter (1 − d^{-1} L ∂_L) on log Z isolates universal subextensive data in thermal QFT: central charges, sphere free energies, topological degeneracies, fracton degeneracies, and the Euler anomaly.

  • Probing radiative electroweak symmetry breaking with colliders and gravitational waves hep-ph · 2024-08-07 · unverdicted · none · ref 13 · internal anchor

    Radiative electroweak symmetry breaking with a logarithmic potential yields analytical vacuum solutions, four thermal history patterns, and supercooled FOPT gravitational waves whose signals combined with collider data can probe conformal scales to 10^5-10^8 GeV.

  • Renormalization and Non-perturbative Dynamics in Conformal Quantum Mechanics quant-ph · 2026-04-16 · unverdicted · none · ref 76

    Computes the beta function for the inverse square potential in conformal quantum mechanics to arbitrary perturbative and non-perturbative orders in both bound state and scattering sectors.