Related papers: More About Discrete Gauge Anomalies
Standard Model (SM) with 15 Weyl fermions per family (lacking the 16th, the sterile right-handed neutrino $\nu_R$) suffers from mixed gauge-gravitational anomalies tied to baryon number plus or minus lepton number ${\bf B} \pm {\bf L}$…
We consider localized anomalies in six dimensional Z_n orbifolds. We give a very simple expression for the contribution of a bulk fermion to the fixed point gauge anomaly that is independent of the order n of the orbifold twist. We show it…
Krauss and Wilczek have shown that an unbroken discrete gauge symmetry is respected by gravitationally mediated processes. This has led to a search for such a symmetry compatible with the standard model or MSSM that would protect protons…
We discuss the generalization to global gauge anomalies of the familiar procedure for the cancellation of local gauge anomalies in effective theories of spontaneously broken symmetries. We illustrate this mechanism in a recently proposed…
I remark that the weak mixing angle in the standard model may be computed even in the absence of a grand unification symmetry. In particular, if there is an additional gauged $U(1)$ symmetry at some large scale which can be made…
We discuss the anomalous magnetic moment of fermion in a realistic SU(3) model of gauge-Higgs unification compactified on an orbifold S^1/Z_2 including Z_2-odd bulk mass for fermions. An operator analysis implies that the anomalous magnetic…
We show that there are discrete gauge symmetries protect naturally heavy X particles from decaying into the ordinary light particles in the supersymmetric standard model. This makes the proposal very attractive that the superheavy X…
It is usually believed that there are no perturbative anomalies in supersymmetric gauge theories beyond the well-known chiral anomaly. In this paper we revisit this issue, because previously given arguments are incomplete. Specifically, we…
We study global anomalies of discrete gauge symmetries in six-dimensional supergravities and their realizations in F-theory. We explicitly construct a discrete Green-Schwarz mechanism that depends on the choice of a coupling constant and on…
We propose two supersymmetric Standard Models (SMs) with decaying and stable dark matter (DM) particles. To explain the SM fermion masses and mixings and have a heavy decay DM particle S, we consider the Froggatt-Nielsen mechanism by…
When M-theory is compactified on G_2-holonomy manifolds with conical singularities, charged chiral fermions are present and the low-energy four-dimensional theory is potentially anomalous. We reconsider the issue of anomaly cancellation,…
We study possible anomaly-free discrete R-symmetries that avoid the \mu-problem and the dangerous D\leq 5 operators considering charge assignments that do not commute with the traditional grand unifying simple groups, such as SU(5) or…
The conditions for the absence of gauge anomalies in effective field theories (EFT) are rivisited. General results from the cohomology of the BRST operator do not prevent potential anomalies arising from the non-renormalizable sector, when…
We establish the non-perturbative validity of the gauge anomaly cancellation condition in an effective electroweak theory of massless fermions with finite momentum cut-off and Fermi interaction. The requirement that the current is conserved…
In particle physics model building discrete symmetries are often invoked to forbid unwanted or dangerous couplings. A classical example is the R-parity of the MSSM, which guarantees the absence of dimension four baryon- and lepton-number…
We extend the well-known 't Hooft anomaly matching conditions for continuous global symmetries to discrete groups. We state the matching conditions for all possible anomalies which involve discrete symmetries explicitly. There are two types…
In this note, we discuss the consistency conditions which a discrete $Z_N$ symmetry should satisfy in order that it is not violated by gauge and gravitational instantons. As examples, we enlist all the $Z_N$ ${\cal R}$-symmetries as well as…
We review and clarify the cancellation conditions for gauge anomalies which occur when N=1, D=4 supergravity is coupled to a Kahler non-linear sigma-model with gauged isometries and Fayet-Iliopoulos couplings. For a flat sigma-model target…
We investigate the predictions of anomaly-free dark matter models for direct and indirect detection experiments. We focus on gauge theories where the existence of a fermionic dark matter candidate is predicted by anomaly cancellation, its…
The anomaly of a discrete symmetry is defined as the Jacobian of the path-integral measure. Assuming that the anomaly at low energies is cancelled by the Green-Schwarz (GS) mechanism at a fundamental scale, we investigate possible Kac-Moody…