Related papers: Axion Mass from Magnetic Monopole Loops
We consider a compact abelian Higgs model in 3+1 dimensions with a topological axion term and construct its dual theories for both bulk and boundary at strong coupling. The model may be viewed as describing a superconductor with magnetic…
Rotations of axion fields in the early universe can produce dark matter and the matter-antimatter asymmetry of the universe. We point out that the rotation can generate an observable amount of a stochastic gravitational-wave (GW)…
The axion particle may or may not exist, but the axion field can be used, as shown here, in an explicitly local formulation of a chiral U(1) gauge theory with both classical and quantum gauge invariance. Nonabelian analogues of axion…
We show that, contrary to assertions in the literature, the main contribution to the axion-photon coupling need not be quantized in the units proportional to $e^2$. In particular, we discuss a loophole in the argument for this quantization…
A general scheme for axion electrodynamics is given, in which a surrounding medium of constant permittivity and permeability is assumed. Then, as an application we give simple numerical estimates for the electromagnetic current density…
Pair-creation of charged particles in a strong gauge-field background - the renowned Schwinger effect - can strongly alter the efficiency of gauge-field production during axion inflation. It is therefore crucial to have a clear…
We study a theory less explored in the literature, that of a massive abelian gauge boson interacting with a massless fermion. In this framework we calculate the electromagnetic potentials created by a point like massless charge. We…
Memory effects of gravitational waves from astronomical events or primordial universe might have the information of new physics. It is intriguing to observe that the memory effect exists in electrodynamics as a net momentum kick, while the…
We report on a search for ultra-low-mass axion-like dark matter by analysing the ratio of the spin-precession frequencies of stored ultracold neutrons and $^{199}$Hg atoms for an axion-induced oscillating electric dipole moment of the…
The placement of a magnetic monopole into an electrically-neutral chiral plasma with a non-zero axial density results in an electric polarization of the matter. The electric current produced by the chiral magnetic effect is balanced by…
We show that axions can be produced from Abelian-Higgs cosmic strings due to the axion-gauge coupling. The strong magnetic field is confined in the string, and the electric field is induced around the moving string, allowing axion…
We investigate the axion inflation model derived by poly-instanton effects in type II superstring theories. Poly-instanton effects are instanton effects corrected by another instanton and it can generate the modulus-axion potential with the…
The highly populated, low-energy excitations of a scalar field of mass $m_a\sim 10^{-22}\,\textrm{eV}$ can represent the full dark matter content of the universe and alleviate some tensions in the standard cosmological scenario on…
Understanding axion production in the early Universe remains a pivotal challenge, given the axion as a compelling cold dark matter candidate. Conventional misalignment scenarios often overlook the possibility that a large initial axion…
We show that a recent constraint on the cosmic birefringence effect due to dark energy can be related to the constraints on the coupling of axion dark matter to photon, by relying on a simple model of two-axion alignment mechanism with…
We evaluate the efficiency of axion production from spatially random initial conditions in the axion field, so a network of axionic strings is present. For the first time, we perform numerical simulations which fully account for the large…
We investigate the instability due to dynamical axion field near the topological phase transition of insulators. We first point out that the amplitude of dynamical axion field is bounded for magnetic insulators in general, which suppresses…
The electric Weak Gravity Conjecture demands that axions with large decay constant $f$ couple to light instantons. The resulting large instantonic corrections pose problems for natural inflation. We explore an alternative argument based on…
Studies of Majorana bound states in semiconducting nanowires frequently neglect the orbital effect of magnetic field. Systematically studying its role leads us to several conclusions for designing Majoranas in this system. Specifically, we…
Axion-like fields are naturally generated by a mechanism of anomaly cancellation of one or more anomalous gauge abelian symmetries at the Planck scale, emerging as duals of a two-form from the massless bosonic sector of string theory. This…