We present a detailed analysis (including redshift tomography) of the cosmic dipoles in the Keck+VLT quasar absorber and in the Union2 SnIa samples. We show that the fine structure constant cosmic dipole obtained through the Keck+VLT quasar absorber sample at 4.1σ level is anomalously aligned with the corresponding dark energy dipole obtained through the Union2 sample at 2σ level. The angular separation between the two dipole directions is 11.3 • ± 11.8 • . We use Monte Carlo simulations to find the probability of obtaining the observed dipole magnitudes with the observed alignment, in the context of an isotropic cosmological model with no correlation between dark energy and fine structure constant α. We find that this probability is less than one part in 10 6 . We propose a simple physical model (extended topological quintessence) which naturally predicts a spherical inhomogeneous distribution for both dark energy density and fine structure constant values. The model is based on the existence of a recently formed giant global monopole with Hubble scale core which also couples non-minimally to electromagnetism. Aligned dipole anisotropies would naturally emerge for an off-centre observer for both the fine structure constant and for dark energy density. This model smoothly reduces to ΛCDM for proper limits of its parameters. Two predictions of this model are (a) a correlation between the existence of strong cosmic electromagnetic fields and the value of α and (b) the existence of a dark flow on Hubble scales due to the repulsive gravity of the global defect core ('Great Repulser') aligned with the dark energy and α dipoles. The direction of the dark flow is predicted to be towards the spatial region of lower accelerating expansion. Existing data about the dark flow are consistent with this prediction.

We use a global pixel based estimator to identify the axis of the residual Maximum Temperature Asymmetry (MTA) (after the dipole subtraction) of the WMAP 7 year Internal Linear Combination (ILC) CMB temperature sky map. The estimator is based on considering the temperature differences between opposite pixels in the sky at various angular resolutions (4 • − 15 • and selecting the axis that maximizes this difference. We consider three large scale Healpix resolutions (N side = 16 (3.7 • ), N side = 8 (7.3 • ) and N side = 4 (14.7 • )). We compare the direction and magnitude of this asymmetry with three other cosmic asymmetry axes (α dipole, Dark Energy Dipole and Dark Flow) and find that the four asymmetry axes are abnormally close to each other. We compare the observed MTA axis with the corresponding MTA axes of 10 4 gaussian isotropic simulated ILC maps (based on ΛCDM). The fraction of simulated ILC maps that reproduces the observed magnitude of the MTA asymmetry and alignment with the observed α dipole is in the range of 0.1% − 0.5% (depending on the resolution chosen for the CMB map). The corresponding magnitude+alignment probabilities with the other two asymmetry axes (Dark Energy Dipole and Dark Flow) are at the level of about 1%. We propose Extended Topological Quintessence as a physical model qualitatively consistent with this coincidence of directions.PACS numbers: 98.80. Es,98.65.Dx,98.62.Sb

We analyze the most salient cosmological features of axions in extensions of the Standard Model with a gauged anomalous extra U (1) symmetry. The model is built by imposing the constraint of gauge invariance in the anomalous effective action, which is extended with Wess-Zumino counterterms. These generate axion-like interactions of the axions to the gauge fields and a gauged shift symmetry. The scalar sector is assumed to acquire a non-perturbative potential after inflation, at the electroweak phase transition, which induces a mixing of the Stückelberg field of the model with the scalars of the electroweak sector, and at the QCD phase transition. We discuss the possible mechanisms of sequential misalignments which could affect the axions of these models, and generated, in this case, at both transitions. We compute the contribution of these particles to dark matter, quantifying their relic densities as a function of the Stückelberg mass. We also show that models with a single anomalous U(1) in general do not account for the dark energy, due to the presence of mixed U (1) − SU (3) anomalies.1 Given its important role as a possible solution of the strong CP problem [1] as well as a candidate for the dark matter of the universe, the study of axions [2, 3] [4, 5, 6, 7] (see [8] for an overview) has received momentum both at theoretical and experimental level along the years. The invisible axion owes its origin to a global U (1) P Q (Peccei-Quinn, PQ) symmetry which is spontaneously broken in the early universe and explicitly broken to a discrete Z N symmetry by instanton effects at the QCD phase transition [9]. The breaking occurs at a temperature T P Q below which the symmetry is nonlinearly realized. Strings and domain walls relics, which are typical of axion models and are a problem in ordinary PQ cosmology, can be avoided by introducing inflation to account for their dilution, or by embedding the model into more general constructions based on theories of Grand Unification [10].The almost massless nature of the axion and its suppressed coupling to the fields of the Standard Model are consequences of the fact that this field is associated with the phase of a global anomalous symmetry. Both properties are related to the same scale, the axion decay constant f a ∼ 10 10 − 10 12 GeV.The implications of the PQ axion in cosmology, both in supersymmetric and in non supersymmetric models, have been explored to a finer level of detail. For instance, the axion plays an important role in determining the structure of the primordial perturbations [11,12,13], where it can act as a curvaton.The gauging of an anomalous symmetry has some important effects on the properties of this pseudoscalar, first among all the appearance of independent mass and couplings to the gauge fields. This scenario allows a wider region of parameter space where to look for these particles. For this reason, axion-like fields, which are at the center of several investigations, are unlikely to find any significant and fundamental formulation without an under...

We present a supersymmetric extension of the Standard Model (USSM-A) with an anomalous U (1) and Stückelberg axions for anomaly cancellation, generalizing similar non-supersymmetric constructions. The model, built by a bottom-up approach, is expected to capture the low-energy supersymmetric description of axionic symmetries in theories with gauged anomalous abelian interactions, previously explored in the non-supersymmetric case for scenarios with intersecting branes. The choice of a USSM-like superpotential, with one extra singlet superfield and an extra abelian symmetry, allows a physical axion-like particle in the spectrum. We describe some general features of this construction and in particular the modification of the dark-matter sector which involves both the axion and several neutralinos with an axino component. The axion is expected to be very light in the absence of phases in the superpotential but could acquire a mass which can also be in the few GeV range or larger. In particular, the gauging of the anomalous symmetry allows independent mass/coupling interaction to the gauge fields of this particle, a feature which is absent in traditional (invisible) axion models. We comment on the general implications of our study for the signature of moduli from string theory due to the presence of these anomalous symmetries.