The joint analysis of galaxy-galaxy lensing and galaxy clustering is a promising method for inferring the growth function of large-scale structure. Anticipating a near future application of this analysis to Dark Energy Survey (DES) measurements of galaxy positions and shapes, we develop a practical approach to modeling the assumptions and systematic effects affecting the joint analysis of small-scale galaxy-galaxy lensing and large-scale galaxy clustering. Introducing parameters that characterize the halo occupation distribution (HOD), photometric redshift uncertainties, and shear measurement errors, we study how external priors on different subsets of these parameters affect our growth constraints. Degeneracies within the HOD model, as well as between the HOD and the growth function, are identified as the dominant source of complication, with other systematic effects being subdominant. The impact of HOD parameters and their degeneracies necessitate the detailed joint modeling of the galaxy sample that we employ. We conclude that DES data will provide powerful constraints on the evolution of structure growth in the Universe, conservatively/optimistically constraining the growth function to 7.9%/4.8% with its first-year data that cover over 1000 square degrees, and to 3.9%/2.3% with its full five-year data that will survey 5000 square degrees, including both statistical and systematic uncertainties.

The Milky Way is surrounded by a gravitationally bound gas corona extending up to the Galaxy’s virial radius. Interactions of cosmic-ray particles with this gas give rise to energetic secondary gamma rays and neutrinos. We present a quantitative analysis of the neutrino and gamma-ray fluxes from the corona of the Milky Way together with a combined contribution of coronae of other galaxies. The high-energy neutrino flux is insufficient to explain the IceCube results, while the contribution to the FERMI-LAT diffuse gamma-ray flux is not negligible.

We study the simultaneous evolution of electron, neutrino, and quark asymmetries and large-scale hypermagnetic fields in the symmetric phase of the electroweak plasma in the temperature range $100\mathrm{GeV}\le T\le 10\mathrm{TeV}$, taking into account the chirality flip processes via inverse Higgs decays and fermion number violation due to Abelian anomalies. We present a derivation of the coefficient of the Chern-Simons term for the hypercharge gauge field, showing that the left-handed and right-handed components of each fermion species contribute with opposite sign. This is in contrast to the results presented in some of the previous works. The ${\mathrm{U}}_{\mathrm{Y}}(1)$ Chern-Simons term affects the resulting anomalous magnetohydrodynamic equations. We solve the resulting coupled evolution equations for the lepton and baryon asymmetries, as well as the hypermagnetic field to obtain their time evolution along with their values at the electroweak phase transition ($T_{\mathrm{EW}}\sim 100\mathrm{GeV}$) for a variety of critical ranges for their initial values at $T=10\mathrm{TeV}$. We first investigate the results of this sign change by directly comparing our results with those obtained in one of the previous works and find that matter asymmetry generation increases considerably in the presence of a strong hypermagnetic field. Furthermore, we find that a strong hypermagnetic field can generate matter asymmetry starting from absolutely zero asymmetry, while matter asymmetry can generate a hypermagnetic field provided the initial value of the latter is nonzero.

We provide a variant model of a strongly interacting massive particle (SIMP), where composite dark matter (DM) comes from a strongly interacting U(1) theory. We first explain a non-Abelian version of the model with an additional singlet field, which is mixed with the Higgs field to maintain kinetic equilibrium between the hidden and Standard Model (SM) sectors. The mixing leads to signals that would be detected by future collider experiments, direct DM detection experiments, and beam-dump experiments. Then we investigate a U(1) theory with a scalar monopole, where U(1) charged particles are confined by a monopole condensation. In this model, the radial component of the monopole can mix with the Higgs field, so that we do not need to introduce the additional singlet field.

We propose a novel approach to measure the branching ratios of the leptonic ${\eta }^{(\prime )}\to {\mu }^{+}{\mu }^{-}$ decays by using charmed meson decays, namely, $D_{(s)}^{+}\to {\pi }^{+}{\eta }^{(\prime )}(\to {\mu }^{+}{\mu }^{-})$ and $D^0\to K^{-}{\pi }^{+}{\eta }^{(\prime )}(\to {\mu }^{+}{\mu }^{-})$. We advocate that the data available at LHCb can already yield a new measurement of $\mathrm{Br}(\eta \to {\mu }^{+}{\mu }^{-})$ with accuracy competitive with the current world average. We also estimate that using the data collected by LHCb between 2015 and 2018 in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of $5.0{\mathrm{fb}}^{-1}$, the relative uncertainties to this branching ratio can be reduced down to $\sim 10\%$. We also show that the first observation of $\mathrm{Br}({\eta }^{\prime }\to {\mu }^{+}{\mu }^{-})$ may be possible with the upgrade of the LHCb experiment.

Lepton number violation plays an essential role in many scenarios of neutrino mass generation and also provides new clues to search new physics beyond the standard model. We consider the neutrinophilic two-Higgs-doublet model ($\nu \text{−}2\mathrm{HDM}$) where additional right-handed neutral fermions $N_{Ri}$ and a complex singlet scalar $\sigma$ are also involved. In the scalar sector, the global $U(1{)}_L$ symmetry is spontaneously broken, leading to Nambu-Goldstone boson, the Majoron $J$, accompanied by the Majorana neutrino mass generation. We find that the massless Majoron will induce large invisible Higgs decay, and current experiments have already set constraints on relevant parameters. For the first time, we point out that the $\nu \text{−}2\mathrm{HDM}$ with $N_{Ri}$ can be distinguished from other seesaw by the same sign trilepton signature $3{\ell }^{\pm }4j+{\cancel{E}}_T$. More interesting, for the $\mathcal{O}(\mathrm{keV})$ scale Majoron, it is a good candidate of decaying dark matter to interpret the 3.5 and 511 keV line excesses by two different parameter spaces.

We present the evolution of a supersonic wind interacting with a boson star (BS) and compare the resulting wind density profile with that of the shock cone formed when the wind is accreted by a nonrotating black hole (BH) of the same mass. The physical differences between these accretors are that a BS, unlike a BH, has no horizon nor a mechanical surface, and thus the wind is expected to trespass the BS. Despite these conditions, on the BS space-time, the gas achieves a stationary flux with the gas accumulating in a high-density elongated structure comparable to the shock cone formed behind a BH. The highest density resides in the center of the BS, whereas in the case of the BH, it is found on the downstream part of the BH near the event horizon. The maximum density of the gas is smaller in the BS case than in the BH case. Our results indicate that the highest density of the wind is more similar on the BS to that on the BH when the BS has high self-interaction, when it is more compact and when the wind velocity is higher. We expect this and similar analyses help us know whether BSs can still be black hole mimickers or can be ruled out.

Motivated by holographic models of a (pseudo)conformal Universe, we carry out a complete analysis of linearized metric perturbations in the time-dependent two-brane setup of the Lykken-Randall type. We present the equations of motion for the scalar, vector and tensor perturbations and identify light modes in the spectrum, which are scalar radion and transverse-traceless graviton. We show that there are no other modes in the discrete part of the spectrum. We pay special attention to properties of light modes and show, in particular, that the radion has red power spectrum at late times, as anticipated on holographic grounds. Unlike the graviton, the radion survives in the single-brane limit, when one of the branes is sent to the adS boundary. These properties imply that potentially observable features characteristic of the 4d (pseudo)conformal cosmology, such as statistical anisotropy and specific shapes of non-Gaussianity, are inherent also in holographic conformal models as well as in brane world inflation.

We propose a new parametrization of the background equations of motion corresponding to (canonical) single-field models of inflation, which allows a better understanding of the general properties of the solutions and of the corresponding predictions in the inflationary observables. Based on the tools of dynamical systems, the method suggests that inflation comes in two flavors: power-law and de Sitter. Power-law inflation seems to occur for a restricted type of potentials, whereas de Sitter inflation has a much broader applicability. We also show a general perturbative method, by means of series expansion, to solve the new equations of motion around the critical point of the de Sitter type and how the method can be used for arbitrary models of de Sitter inflation. It is then argued that for the latter there are two general classes of inflationary solutions, given in terms of the behavior of the tensor-to-scalar ratio as a function of the number $N$ of $e$-folds before the end of inflation: $r\sim N^{-1}$ (Class I) or $r\sim N^{-2}$ (Class II). We give some examples of the two classes in terms of known scalar field potentials and compare their general predictions with constraints obtained from observations.

We propose a generalized star product that deviates from the standard one when the fields are considered at different spacetime points by introducing a form factor in the standard star product. We also introduce a recursive definition by which we calculate the explicit form of the generalized star product at any number of spacetime points. We show that our generalized star product is associative and cyclic at linear order. As a special case, we demonstrate that our recursive approach can be used to prove the associativity of standard star products for same or different spacetime points. The introduction of a form factor has no effect on the standard Lagrangian density in a noncommutative spacetime because it reduces to the standard star product when spacetime points become the same. We show that the generalized star product leads to physically consistent results and can fit the observed data on hemispherical anisotropy in the cosmic microwave background radiation.

The magnetic dipole radiation model is currently the best approach we have to explain pulsar radiation. However, a most characteristic parameter of the observed radiation, the braking index $n_{\text{obs}}$, shows deviations for all the eight best studied isolated pulsars, from the simple model prediction $n_{\text{dip}}=3$. The index depends upon the rotational frequency and its first and second time derivatives but also on the assumption that the magnetic dipole moment and inclination angle and the moment of inertia of the pulsar are constant in time. In a recent paper [Phys. Rev. D 91, 063007 (2015)], we showed conclusively that changes in the moment of inertia with frequency alone cannot explain the observed braking indices. Possible observational evidence for the magnetic dipole moment migrating away from the rotational axis at a rate $\dot{\alpha }\sim 0.6°$ per 100 years over the lifetime of the Crab pulsar has been recently suggested by Lyne et al. In this paper, we explore the magnetic dipole radiation model with constant moment of inertia and magnetic dipole moment but variable inclination angle $\alpha$. We first discuss the effect of the variation of $\alpha$ on the observed braking indices and show they all can be understood. However, no explanation for the origin of the change in $\alpha$ is provided. After discussion of the possible source(s) of magnetism in pulsars, we propose a simple mechanism for the change in $\alpha$ based on a toy model in which the magnetic structure in pulsars consists of two interacting dipoles. We show that such a system can explain the Crab observation and the measured braking indices.

We derive the analytical time delay of light propagating in the equatorial plane and parallel to the velocity of a moving Kerr-Newman black hole up to the second post-Minkowskian order via integrating the null geodesic equations. The velocity effects are expressed by a very compact form. We then concentrate on analyzing the magnitudes of the correctional effects on the second-order contributions to the delay and discuss their possible detection. Our result in the first post-Minkowskian approximation is in agreement with Kopeikin and Schäfer’s formulation which is based on the retarded Liénard-Wiechert potential.

We investigate the critical behavior of pion superfluidity in the framework of the functional renormalization group (FRG). By solving the flow equations in the SU(2) linear sigma model at finite temperature and isospin density, and making comparison with the fixed point analysis of a general $O(N)$ system with continuous dimension, we find that the pion superfluidity is a second order phase transition subject to an $O(2)$ universality class with a dimension crossover from $d_c=4$ to $d_c=3$. This phenomenon provides a concrete example of dimension reduction in thermal field theory. The large-$N$ expansion gives a temperature independent critical exponent $\beta$ and agrees with the FRG result only at zero temperature.

The flavor changing decays of the top quark are severely suppressed in the standard model by virtue of the Glashow-Iliopoulos-Maiani mechanism. Many beyond the standard model extensions predict the decay rates at a level that is observable in the LHC. We perform a complete one-loop calculation of the flavor changing top quark decays $t\to c\gamma$ and $t\to ch$ in the universal extradimensional model. Apart from considering the decay rates in the minimal version of the model, we also calculate the rates in the nonminimal scenario where the presence of boundary localized terms interestingly modifies the setup. We find that the decay rates in the minimal variant of the model do not change much from their standard model values. In the nonminimal version of this model, these decay rates can be higher for specific choices of the boundary localized parameters for a certain range of inverse compactification radius. But these model parameters lead to Kaluza-Klein particle masses that are in tension with various searches at the LHC.

A search is presented for the production of two Higgs bosons in final states containing two photons and two bottom quarks. Both resonant and nonresonant hypotheses are investigated. The analyzed data correspond to an integrated luminosity of $19.7{\mathrm{fb}}^{-1}$ of proton-proton collisions at $\sqrt{s}=8\mathrm{TeV}$ collected with the CMS detector. Good agreement is observed between data and predictions of the standard model (SM). Upper limits are set at 95% confidence level on the production cross section of new particles and compared to the prediction for the existence of a warped extra dimension. When the decay to two Higgs bosons is kinematically allowed, assuming a mass scale ${\mathrm{\Lambda }}_{\mathrm{R}}=1\mathrm{TeV}$ for the model, the data exclude a radion scalar at masses below 980 GeV. The first Kaluza-Klein excitation mode of the graviton in the RS1 Randall-Sundrum model is excluded for masses between 325 and 450 GeV. An upper limit of 0.71 pb is set on the nonresonant two-Higgs-boson cross section in the SM-like hypothesis. Limits are also derived on nonresonant production assuming anomalous Higgs-boson couplings.

Level-rank duality relates the observables of two different Chern-Simons theories in which the roles of the Chern-Simons level and the rank of the gauge group are exchanged. In this paper, we explore the consequences of this duality in the realm of topological string theory. We show that this duality induces a number of identities between the open Gromov-Witten invariants of the geometries associated with a knot $\mathcal{K}$ and its mirror image $\tilde{\mathcal{K}}$. We show how these identities arise both in the A model and in the dual B model.

In this paper we explore the correspondence between four-dimensional Born-Infeld theory and five-dimensional classical gravity. The Born-Infeld theory side corresponds to the low-energy effective theory for open strings ending on coincident D3-branes in a (slowly varying) background Kalb-Ramond field, including all higher-derivative corrections. On the gravity side one has the gravitational (closed-string) description of D3-branes in the same background Kalb-Ramond field and the correspondence is thus a consequence of the open/closed-string duality. According to the correspondence the gravity side provides a description of the strong coupling limit of Born-Infeld theory. This is a correspondence between effective theories in a similar sense as in the fluid/gravity correspondence. We match the Born-Infeld and gravity sides up to, and including, two-derivative corrections. To this end, we find a new gravity solution for D3-branes with flat embedding in the background of an arbitrary constant background Kalb-Ramond field and show that there are no two-derivative corrections to this for a slowly varying Kalb-Ramond field.

We rederive relativistic hydrodynamics as a Lagrangian effective theory using the doubled coordinates technique, allowing us to include dissipative terms. We include Navier-Stokes shear and bulk terms, as well as Israel-Stewart relaxation time terms, within this formalism. We show how the inclusion of shear dissipation forces the inclusion of the Israel-Stewart term into the theory, thereby providing an additional justification for the form of this term.

Exact expressions have been proposed for correlation functions of the large-$N$ (planar) limit of the ($1+1$)-dimensional $\mathrm{SU}(N)\times \mathrm{SU}(N)$ principal chiral sigma model. These were obtained with the form-factor bootstrap. The short-distance form of the two-point function of the scaling field $\mathrm{\Phi }(x)$ was found to be $N^{-1}⟨\mathrm{Tr}\mathrm{\Phi }(0{)}^{†}\mathrm{\Phi }(x)⟩=C_2{\ln }^{2}mx$, where $m$ is the mass gap, in agreement with the perturbative renormalization group. Here we point out that the universal coefficient $C_2$ is proportional to the mean first-passage time of a Lévy flight in one dimension. This observation enables us to calculate $C_2=1/16\pi$.

We present an exact renormalization group (RG) analysis of $O(N)$-invariant scalar field theory about the Gaussian fixed point. We prove a series of statements that, taken together, show that the nonpolynomial eigenperturbations found in the local potential approximation at the linearized level do not lead to new interactions, i.e. enlarge the universality class, in the local potential approximation nor treated exactly. Nonperturbatively, their RG flow does not emanate from the fixed point. For the equivalent Wilsonian effective action, they can be reexpressed in terms of the usual couplings to polynomial interactions, which can furthermore be tuned to be as small as desired for all finite RG time. For the infrared cutoff Legendre effective action, this can also be done for the infrared evolution. We explain why this is nevertheless consistent with the fact that the large field behavior is fixed by these perturbations.