English
Related papers

Related papers: On critical exponents without Feynman diagrams

200 papers

The magnetic line defect in the $O(N)$ model gives rise to a non-trivial one-dimensional defect conformal field theory of theoretical and experimental value. This model is considered here in $d=4-\varepsilon$ and the full spectrum of defect…

High Energy Physics - Theory · Physics 2025-08-26 Jake Belton , Nadav Drukker , Ziwen Kong , Andreas Stergiou

We compute the contribution to the anomalous dimension of the twist-2 operators in N=4 SYM theory, which is proportional to the number of fermion loops inside Feynman diagrams or, formally, to the number of fermions. The result was obtained…

High Energy Physics - Theory · Physics 2022-11-30 V. N. Velizhanin

The determinant method in the conformal bootstrap is applied for the critical phenomena of a single polymer in arbitrary $D$ dimensions. The scale dimensions (critical exponents) of the polymer ($2< D \le 4$) and the branched polymer ($3 <…

High Energy Physics - Theory · Physics 2019-12-06 S. Hikami

We simplify, to a single integral of dilogarithms, the least tractable O(1/N^3) contribution to the large-N critical exponent $\eta$ of the non-linear sigma-model, and hence $\phi^4$-theory, for any spacetime dimensionality, D. It is the…

High Energy Physics - Theory · Physics 2016-09-06 D. J. Broadhurst , A. V. Kotikov

We apply numerical conformal bootstrap techniques to the four-point function of a Weyl spinor in 4d non-supersymmetric CFTs. We find universal bounds on operator dimensions and OPE coefficients, including bounds on operators in mixed…

High Energy Physics - Theory · Physics 2019-02-19 Denis Karateev , Petr Kravchuk , Marco Serone , Alessandro Vichi

The Wilson-Fisher criticality provides a paradigm for a large class of phase transitions in nature (e.g., helium, ferromagnets). In the three dimension, Wilson-Fisher critical points are not exactly solvable due to the strongly-correlated…

Strongly Correlated Electrons · Physics 2023-12-08 Chao Han , Liangdong Hu , W. Zhu

The effect of the $\ord{\partial^4}$ terms of the gradient expansion on anomalous dimension $\eta$ and the correlation length's critical exponent $\nu$ of the Wilson-Fisher fixed point has been determined for the Euclidean $O(N)$ model for…

High Energy Physics - Theory · Physics 2018-04-04 Z. Peli , S. Nagy , K. Sailer

We use analytic bootstrap techniques for a CFT with an interface or a boundary. Exploiting the analytic structure of the bulk and boundary conformal blocks we extract the CFT data. We further constrain the CFT data by applying the equation…

High Energy Physics - Theory · Physics 2021-09-21 Parijat Dey , Alexander Söderberg

In this work we initiate the conformal bootstrap program for ${\mathcal N}=2$ superconformal field theories in four dimensions. We promote an abstract operator-algebraic viewpoint in order to unify the description of Lagrangian and…

High Energy Physics - Theory · Physics 2019-03-25 Christopher Beem , Madalena Lemos , Pedro Liendo , Leonardo Rastelli , Balt C. van Rees

The critical behavior of a non-local scalar field theory is studied. This theory has a non-local quartic interaction term which involves a real power -\beta of the Laplacian. The parameter \beta can be tuned so as to make that interaction…

High Energy Physics - Theory · Physics 2019-12-11 Roberto Trinchero

We compute the two-loop four-point form factor of a length-3 half-BPS operator in planar N=4 SYM, which belongs to the class of two-loop five-point scattering observables with one off-shell color-singlet leg. A new bootstrapping strategy is…

High Energy Physics - Theory · Physics 2021-10-13 Yuanhong Guo , Lei Wang , Gang Yang

Recent work using a large-charge expansion for the $O(N)$ Wilson-Fisher conformal field theory has shown that the anomalous dimensions of large-charge operators can be expressed in terms of a few low-energy constants (LECs) of a…

High Energy Physics - Lattice · Physics 2022-03-02 Hersh Singh

We advocate a strategy of bootstrapping Feynman integrals from just knowledge of their singular behavior. This approach is complementary to other bootstrap programs, which exploit non-perturbative constraints such as unitarity, or…

High Energy Physics - Phenomenology · Physics 2024-11-20 Holmfridur Hannesdottir , Andrew McLeod , Matthew D. Schwartz , Cristian Vergu

We consider the Landau-Ginzburg-Wilson Hamiltonian with O(n)x O(m) symmetry and compute the critical exponents at all fixed points to O(n^{-2}) and to O(\epsilon^3) in a \epsilon=4-d expansion. We also consider the corresponding non-linear…

High Energy Physics - Theory · Physics 2009-11-07 Andrea Pelissetto , Paolo Rossi , Ettore Vicari

We discuss properties of the $\epsilon$-expansion in $d=4-\epsilon$ dimensions. Using Lagrange inversion we write down an exact expression for the value of the Wilson-Fisher fixed point coupling order by order in $\epsilon$ in terms of the…

High Energy Physics - Theory · Physics 2020-04-21 Thomas A. Ryttov

We develop a method for extracting accurate critical exponents from perturbation expansions of the O(n)-symmetric nonlinear sigma-model in D=2+ epsilon dimensions. This is possible by considering the epsilon-expansions in this model as…

High Energy Physics - Theory · Physics 2009-10-31 Hagen Kleinert

Feynman diagrams are calculated by means of their Taylor series expansion in terms of external momenta squared. It is demonstrated in various examples that by the application of conformal mapping and Pad\'{e} approximants, it is possible to…

High Energy Physics - Phenomenology · Physics 2009-10-28 J. Fleischer , O. V. Tarasov

We set up the conventional conformal bootstrap equations in Mellin space and analyse the anomalous dimensions and OPE coefficients of large spin double trace operators. By decomposing the equations in terms of continuous Hahn polynomials,…

High Energy Physics - Theory · Physics 2018-03-14 Parijat Dey , Kausik Ghosh , Aninda Sinha

Higher-point correlation functions encode the data of infinitely many 4-point correlators in conformal field theory (CFT). In this paper, we develop new tools to efficiently extract this data from multi-point crossing equations. Concretely,…

High Energy Physics - Theory · Physics 2025-09-03 António Antunes , Sebastian Harris , Apratim Kaviraj

Recently an efficient numerical method has been developed to implement the constraints of crossing symmetry and unitarity on the operator dimensions and OPE coefficients of conformal field theories (CFT) in diverse space-time dimensions. It…

High Energy Physics - Theory · Physics 2013-10-30 Ferdinando Gliozzi