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Related papers: On the trace anomaly for Weyl fermions

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The chiral anomaly is a phenomenon characteristic of Weyl fermions, which has condensed matter realizations in Weyl semimetals. Efforts to observe smoking gun signatures of the chiral anomaly in Weyl semimetals have mostly focused on a…

Strongly Correlated Electrons · Physics 2019-08-30 Aaron Hui , Yi Zhang , Eun-Ah Kim

We derive explicit anomaly-index formulas for four-dimensional Weyl fermions charged under the finite symmetries $\mathrm{Spin}\times\mathbb Z_n$ and $\mathrm{Spin}\times_{\mathbb Z_2^{\mathrm F}}\mathbb Z_{2m}^{\mathrm F}$. The strategy is…

High Energy Physics - Theory · Physics 2026-05-29 Zheyan Wan

Weyl semimetals provide the realization of Weyl fermions in solid-state physics. Among all the physical phenomena that are enabled by Weyl semimetals, the chiral anomaly is the most unusual one. Here, we report signatures of the chiral…

The trace anomaly is relevant to the renormalisation of the unpolarised parton distributions. The role of the trace anomaly in F_2 is compared with the axial anomaly in g_1.

High Energy Physics - Phenomenology · Physics 2009-10-28 S. D. Bass

In a theory of a Dirac fermion field coupled to a metric-axial-tensor (MAT) background, using a Schwinger-DeWitt heat kernel technique, we compute non-perturbatively the two (odd parity) trace anomalies. A suitable collapsing limit of this…

High Energy Physics - Theory · Physics 2018-09-26 L. Bonora , M. Cvitan , P. Dominis Prester , S. Giaccari , M. Paulisic , T. Stemberga

Weyl fermions are two-component chiral fermions in (3+1)-dimensions. When coupled to a gauge field, the Weyl fermion is known to have an axial anomaly, which means the current conservation of the left-handed and right-handed Weyl fermions…

Strongly Correlated Electrons · Physics 2013-06-13 Chao-Xing Liu , Peng Ye , Xiao-Liang Qi

We study the definition of trace anomalies for models of Dirac and Weyl fermions coupled to a metric and a gauge potential. While in the non-perturbative case the trace anomaly is the response of the effective action to a Weyl…

High Energy Physics - Theory · Physics 2021-07-19 Loriano Bonora

The Weyl anomaly problem is treated within a purely geometrical context. Arguments are given that hint at a possible classical origin of the conformal anomaly in the Riemannian nature of the background geometry where the matter fields play…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Israel Quiros

Weyl semimetals are materials where electrons behave effectively as a kind of massless relativistic particles known asWeyl fermions. These particles occur in two flavours, or chiralities, and are subject to quantum anomalies, the breaking…

Weyl semimetal with Weyl fermions at Fermi energy is one of the topological materials, and is a condensed-matter realization of the relativistic fermions. However, there are several crucial differences such as the shift of Fermi energy,…

Mesoscale and Nanoscale Physics · Physics 2019-03-27 Hiroaki Ishizuka , Naoto Nagaosa

Three-dimensional condensed matter incarnations of Weyl fermions generically have a tilted dispersion---in sharp contrast with their elusive high-energy relatives where a tilt is forbidden by Lorentz invariance, and with the low-energy…

Materials Science · Physics 2016-08-24 M. Udagawa , E. J. Bergholtz

Weyl semimetals are predicted to realize the three-dimensional axial anomaly first discussed in particle physics. The anomaly leads to unusual transport phenomena such as the chiral magnetic effect in which an applied magnetic field induces…

Mesoscale and Nanoscale Physics · Physics 2016-11-23 Edwin Barnes , J. J. Heremans , Djordje Minic

Nielsen-Ninomiya theorem forbids Weyl fermions on the lattice which respect the full hypercubic symmetry. By giving up this assumption in a specific way, it is possible to formulate a lattice theory with a single Weyl fermion in four…

High Energy Physics - Lattice · Physics 2010-10-26 Artan Borici

We consider a Dirac fermion in a metric-axial-tensor (MAT) background. By regulating it with Pauli-Villars fields we analyze and compute its full anomaly structure. Appropriate limits of the MAT background allows to recover the anomalies of…

High Energy Physics - Theory · Physics 2020-04-22 Fiorenzo Bastianelli , Matteo Broccoli

Weyl semimetals are one kind of three-dimensional gapless semimetal with nontrivial topology in the momentum space. The chiral anomaly in Weyl semimetals manifests as a charge imbalance between the Weyl nodes of opposite chiralities induced…

Strongly Correlated Electrons · Physics 2015-01-19 Jianhui Zhou , Hao-Ran Chang , Di Xiao

The trace anomaly and anomaly-induced action are evaluated for the two-dimensional $2D$ vector theory with classical conformal symmetry. Implementing local conformal symmetry while preserving the gauge invariance requires either giving up…

High Energy Physics - Theory · Physics 2025-12-19 Samuel W. P. Oliveira , Ilya L. Shapiro

The general structure of trace anomaly, suggested recently by Deser and Shwimmer, is argued to be the consequence of the Wess-Zumino consistency condition. The response of partition function on a finite Weyl transformation, which is…

High Energy Physics - Theory · Physics 2010-11-01 D. R. Karakhanyan , R. P. Manvelyan , R. L. Mkrtchyan

We classify the trace anomaly for parity-invariant non-relativistic Schr\"odinger theories in 2+1 dimensions coupled to background Newton-Cartan gravity. The general anomaly structure looks very different from the one in the z=2 Lifshitz…

High Energy Physics - Theory · Physics 2016-07-06 Roberto Auzzi , Stefano Baiguera , Giuseppe Nardelli

We explore the trace (Weyl) anomaly within a general metric-affine geometry that includes both torsion and nonmetricity. Using the Heat Kernel method and Seeley's algorithm, we compute the Minakshisundaram coefficients for arbitrary…

General Relativity and Quantum Cosmology · Physics 2024-10-03 Sebastian Bahamonde , Yuichi Miyashita , Masahide Yamaguchi

Chiral anomaly and the novel quantum phenomena it induces have been widely studied for Dirac and Weyl fermions. In most typical cases, the Lorentz covariance is assumed and thus the linear dispersion relations are maintained. However, in…

Mesoscale and Nanoscale Physics · Physics 2022-01-21 Lan-Lan Gao , Xu-Guang Huang