Journal of High Energy Physics

We investigate a higher-group structure of massless axion electrodynamics in (3 + 1) dimensions. By using the background gauging method, we show that the higher-form symmetries necessarily have a global semistrict 3-group (2-crossed module) structure, and exhibit ’t Hooft anomalies of the 3-group. In particular, we find a cubic mixed ’t Hooft anomaly between 0-form and 1-form symmetries, which is specific to the higher-group structure.

In this paper, we explore the question of how different gauge choices in a gauge theory affect the tensor product structure of the Hilbert space in configuration space. In particular, we study the Coulomb gauge and observe that the naive gauge potential degrees of freedom cease to be local operators as soon as we impose the Dirac brackets. We construct new local set of operators and compute the entanglement entropy according to this algebra in 2 + 1 dimensions. We find that our proposal would lead to an entanglement entropy that behave very similar to a single scalar degree of freedom if we do not include further centers, but approaches that of a gauge field if we include non-trivial centers. We explore also the situation where the gauge field is Higgsed, and construct a local operator algebra that again requires some deformation. This should give us some insight into interpreting the entanglement entropy in generic gauge theories and perhaps also in gravitational theories.

We consider the generation of neutrino masses via a singly-charged scalar singlet. Under general assumptions we identify two distinct structures for the neutrino mass matrix. This yields a constraint for the antisymmetric Yukawa coupling of the singly-charged scalar singlet to two left-handed lepton doublets, irrespective of how the breaking of lepton-number conservation is achieved. The constraint disfavours large hierarchies among the Yukawa couplings. We study the implications for the phenomenology of lepton-flavour universality, measurements of the W-boson mass, flavour violation in the charged-lepton sector and decays of the singly-charged scalar singlet. We also discuss the parameter space that can address the Cabibbo Angle Anomaly.

In this paper we study for the first time topological defects in the context of nonlocal field theories in which Lagrangians contain infinite-order differential operators. In particular, we analyze domain walls. Despite the complexity of non-linear infinite-order differential equations, we are able to find an approximate analytic solution. We first determine the asymptotic behavior of the nonlocal domain wall close to the vacua. Then, we find a linearized nonlocal solution by perturbing around the well-known local ‘kink’, and show that it is consistent with the asymptotic behavior. We develop a formalism to study the solution around the origin, and use it to verify the validity of the linearized solution. We find that nonlocality makes the width of the domain wall thinner, and the energy per unit area smaller as compared to the local case. For the specific domain wall solution under investigation we derive a theoretical constraint on the energy scale of nonlocality which must be larger than the corresponding symmetry-breaking scale. We also briefly comment on other topological defects like string and monopole.

We clarify some issues concerning the central charges saturated by the extended objects in the SUSY U(1) 4d gauge theory in the Ω-background. The configuration involving the monopole localized at the domain wall is considered in some details. At the rational ratio $ \frac{{{\in_1}}}{{{\in_2}}}=\frac{p}{q} $ the trajectory of the monopole provides the torus (p,q) knot in the squashed three-sphere. Using the relation between the integrable systems of Calogero type at the rational couplings and the torus knots we interpret this configuration in terms of the auxiliary 2d quiver theory or 3d theory with nontrivial boundary conditions. This realization can be considered as the AGT-like representation of the torus knot invariants.

It has recently been demonstrated that black hole dynamics in a large number of dimensions D reduces to the dynamics of a codimension one membrane propagating in flat space. In this paper we define a stress tensor and charge current on this membrane and explicitly determine these currents at low orders in the expansion in $$ \frac{1}{D} $$ . We demonstrate that dynamical membrane equations of motion derived in earlier work are simply conservation equations for our stress tensor and charge current. Through the paper we focus on solutions of the membrane equations which vary on a time scale of order unity. Even though the charge current and stress tensor are not parametrically small in such solutions, we show that the radiation sourced by the corresponding membrane currents is generically of order $$ \frac{1}{D^D} $$ . In this regime it follows that the ‘near horizon’ membrane degrees of freedom are decoupled from asymptotic flat space at every perturbative order in the $$ \frac{1}{D} $$ expansion. We also define an entropy current on the membrane and use the Hawking area theorem to demonstrate that the divergence of the entropy current is point wise non negative. We view this result as a local form of the second law of thermodynamics for membrane motion.

We propose a B − L gauged extension of the Standard Model where light neutrino masses arise from type III seesaw mechanism. Unlike the minimal B − L model with three right handed neutrinos having unit lepton number each, the model with three fermion triplets is however not anomaly free. We show that the leftover triangle anomalies can be cancelled by two neutral Dirac fermions having fractional B − L charges, both of which are naturally stable by virtue of a remnant ℤ2× $$ {\mathbb{Z}}_2^{\prime } $$ symmetry, naturally leading to a two component dark matter scenario without any ad-hoc symmetries. We constrain the model from all relevant phenomenological constraints including dark matter properties. Light neutrino mass and collider prospects are also discussed briefly. Due to additional neutral gauge bosons, the fermion triplets in type III seesaw can have enhanced production cross section in collider experiment.

We explore the possibility of discovering the mirror baryons and electrons of the Mirror Twin Higgs model in direct detection experiments, in a scenario in which these particles constitute a subcomponent of the observed DM. We consider a framework in which the mirror fermions are sub-nano-charged, as a consequence of kinetic mixing between the photon and its mirror counterpart. We consider both nuclear recoil and electron recoil experiments. The event rates depend on the fraction of mirror DM that is ionized, and also on its distribution in the galaxy. Since mirror DM is dissipative, at the location of the Earth it may be in the form of a halo or may have collapsed into a disk, depending on the cooling rate. For a given mirror DM abundance we determine the expected event rates in direct detection experiments for the limiting cases of an ionized halo, an ionized disk, an atomic halo and an atomic disk. We find that by taking advantage of the complementarity of the different experiments, it may be possible to establish not just the multi-component nature of mirror dark matter, but also its distribution in the galaxy. In addition, a study of the recoil energies may be able to determine the masses and charges of the constituents of the mirror sector. By showing that the mass and charge of mirror helium are integer multiples of those of mirror hydrogen, these experiments have the potential to distinguish the mirror nature of the theory. We also carefully consider mirror plasma screening effects, showing that the capture of mirror dark matter particles in the Earth has at most a modest effect on direct detection signals.