arXiv subjects

Yongwei Guo

Publications and source records attributed to Yongwei Guo.

6 recordsLinked to original sources

arXiv2026

Central charges $C_J$ and $C_T$ in QED$_d$-GNY model and scalar QED$_d$

We compute the leading-order $1/N$ corrections to the central charges $C_J$ and $C_T$ in the conformal QED$_d$-Gross-Neveu-Yukawa (GNY) model and the scalar QED$_d$ in $d$ dimensions. The scaling dimensions of the lowest adjoint bilinear scalars are obtained to order $O(1/N)$ for general $d$. In $d=3$, the $U(1)$ Abelian gauge theory possesses a topological $U(1)$ global symmetry, and we evaluate the central charge $C_J^{\text{top}}$ of the topological symmetry current to subleading order in the $1/N$ expansion. Our interest in these theories is primarily motivated by their potential connection to the $SO(5)$ symmetric deconfined quantum critical point (DQCP). We compare the large $N$ results for the central charges $C_J$ and $C_T$ with the conformal data of the $SO(5)$ DQCP obtained from fuzzy sphere and conformal bootstrap. The large $N$ predictions of the QED$_3$-GNY model are found to be in reasonable agreement with the nonperturbative estimates for the $SO(5)$ DQCP.

hep-th↗

arXiv2026

Boundary anomalous dimensions from BCFT: $\phi^{3}$ theories with a boundary and higher-derivative generalizations

We consider the bulk $\phi^3$ deformation of the free boundary conformal field theory in the $\epsilon$ expansion. We determine the leading corrections to the scaling dimensions of boundary fundamental operators and some boundary operator expansion coefficients. Our procedure combines the conformal multiplet recombination with the boundary crossing symmetry. The results cover both the single field case and the multi-field case with $S_{N+1}$ global symmetry, which are associated with the Yang-Lee model and the $(N+1)$-state Potts model respectively. These semi-infinite models describe branched polymers, percolation, and spanning forest at a surface. We generalize these results to some higher derivative theories. In addition, we study the $\phi^{2n+1}$ theories with $n>1$, but only obtain some boundary operator expansion coefficients.

hep-th↗

arXiv2025

Boundary anomalous dimensions from BCFT: O($N$)-symmetric $\phi^{2n}$ theories with a boundary and higher-derivative generalizations

We investigate the $\phi^{2n}$ deformations of the O($N$)-symmetric (generalized) free theories with a flat boundary, where $n\geqslant 2$ is an integer. The generalized free theories refer to the $\Box^k$ free scalar theories with a higher-derivative kinetic term, which is related to the multicritical generalizations of the Lifshitz type. We assume that the (generalized) free theories and the deformed theories have boundary conformal symmetry and O($N$) global symmetry. The leading anomalous dimensions of some boundary operators are derived from the bulk multiplet recombination and analyticity constraints. We find that the $\epsilon^{1/2}$ expansion in the $\phi^6$-tricritical version of the special transition extends to other multicritical cases with larger odd integer $n$, and most of the higher derivative cases involve a noninteger power expansion in $\epsilon$. Using the analytic bootstrap, we further verify that the multiplet-recombination results are consistent with boundary crossing symmetry.

hep-th↗

arXiv2024

Anomalous dimensions from conformal field theory: Generalized $\phi^{2n+1}$ theories

We investigate $\phi^{2n+1}$ deformations of the generalized free theory in the $\epsilon$ expansion, where the canonical kinetic term is generalized to a higher-derivative version. For $n=1$, we use the conformal multiplet recombination method to determine the leading anomalous dimensions of the fundamental scalar operator $\phi$ and the bilinear composite operators $\mathcal J$. Then we extend the $n=1$ analysis to the Potts model with $S_{N+1}$ symmetry and its higher-derivative generalization, in which $\phi$ is promoted to an $N$-component field. We further examine the Chew-Frautschi plots and their $N$ dependence. However, for each integer $n>1$, the leading anomalous dimensions of $\phi$ and $ \mathcal{J}$ are not fully determined and contain one unconstrained constant, which in the canonical cases can be fixed by the results from the traditional diagrammatic method. In all cases, we verify that the multiplet-recombination results are consistent with crossing symmetry using the analytic bootstrap methods.

hep-th↗

arXiv2024

Anomalous dimensions of partially-conserved higher-spin currents from conformal field theory: bosonic $ϕ^{2n}$ theories

In the free $\Box^k$ scalar conformal field theory, there exist conserved and partially-conserved higher-spin currents. We study their anomalous dimensions associated with $ϕ^{2n}$ interaction in the $ε$ expansion. We derive general formulae for the leading corrections from the conformal multiplet recombination, and verify their consistency with crossing symmetry using the Lorentzian inversion formula. The results are further extended to the O($N$) models.

hep-th↗

arXiv2023

Solving anharmonic oscillator with null states: Hamiltonian bootstrap and Dyson-Schwinger equations

As basic quantum mechanical models, anharmonic oscillators are recently revisited by bootstrap methods. An effective approach is to make use of the positivity constraints in Hermitian theories. There exists an alternative avenue based on the null state condition, which applies to both Hermitian and non-Hermitian theories. In this work, we carry out an analytic bootstrap study of the quartic oscillator based on the small coupling expansion. In the Hamiltonian formalism, we obtain the anharmonic generalization of Dirac's ladder operators. Furthermore, the Schrodinger equation can be interpreted as a null state condition generated by an anharmonic ladder operator. This provides an explicit example in which dynamics is incorporated into the principle of nullness. In the Lagrangian formalism, we show that the existence of null states can effectively eliminate the indeterminacy of the Dyson-Schwinger equations and systematically determine $n$-point Green's functions.

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