In this work, we develop a normal product algorithm suitable to the study of anisotropic field theories in flat space, apply it to construct the symmetries generators and describe how their possible anomalies may be found. In particular, we discuss the dilatation anomaly in a scalar model with critical exponent $z=2$ in six spatial dimensions.

For the four-dimensional SU(N) Euclidean Yang-Mills theory in the Landau gauge, we present two sets of gauge field configurations that satisfy the Euclidean equations of motion. These configurations generate four-dimensional chromo-field flux sheets whose spatial cross sections are three-dimensional chromo-field flux tubes. In lattice simulations, they may be detected as center vortices. The first set of gauge field configurations generates chromo-electric flux tubes that should contribute to a chromo-electric flux tube between two static color charges. The string tension ${\sigma }_r$ for two static color charges in representation $r$ then naturally satisfies the Casimir scaling. Applying a gauge transformation to this set of gauge field configurations, we can transform them into those in the maximal Abelian gauge. These transformed configurations generate chromo-electric flux tubes that should contribute to those observed between two static quarks in lattice simulations performed in the maximal Abelian gauge. The second set of gauge field configurations generates chromo-magnetic flux tubes. When rotated in a plane that includes the temporal $x_4$ axis and is perpendicular to the flux tube axis, the rotated gauge field configuration generates a chromo-electric flux tube and should contribute to the chromo-electric flux tubes observed in lattice simulations in the Landau gauge. We also argue that when regulated on a lattice, any of the flux sheet gauge field configurations with a finite flux sheet thickness is located on the Gribov horizon in the infinite lattice volume limit. We thus suggest that these sets of gauge field configurations contribute significantly to the low-energy properties of QCD, particularly the quark confinement.

We present a new code, named COCAL—Compact Object CALculator, for the computation of equilibriums and quasiequilibrium initial data sets of single or binary compact objects of all kinds. In the cocal code, those solutions are calculated on one or multiple spherical coordinate patches covering the initial hypersurface up to the asymptotic region. The numerical method used to solve field equations written in elliptic form is an adaptation of self-consistent field iterations in which Green’s integral formula is computed using multipole expansions and standard finite difference schemes. We extended the method so that it can be used on a computational domain with excised regions for a black hole and a binary companion. Green’s functions are constructed for various types of boundary conditions imposed at the surface of the excised regions for black holes. The numerical methods used in cocal are chosen to make the code simpler than any other recent initial data codes, accepting the second order accuracy for the finite difference schemes. We perform convergence tests for time symmetric single black hole data on a single coordinate patch, and binary black hole data on multiple patches. Then, we apply the code to obtain spatially conformally flat binary black hole initial data using boundary conditions, including the one based on the existence of equilibrium apparent horizons.

What is the size of the most massive object one expects to find in a survey of a given volume? In this paper, we present a solution to this problem using extreme-value statistics, taking into account primordial non-Gaussianity and its effects on the abundance and the clustering of rare objects. We calculate the probability density function (PDF) of extreme-mass clusters in a survey volume, and show how primordial non-Gaussianity shifts the peak of this PDF. We also study the sensitivity of the extreme-value PDFs to changes in the mass functions, survey volume, redshift coverage, and the normalization of the matter power spectrum, ${\sigma }_8$. For “local” non-Gaussianity parametrized by $f_{\mathrm{NL}}$, our correction for the extreme-value PDF due to the bias is important when $f_{\mathrm{NL}}\gtrsim 100$, and becomes more significant for wider and deeper surveys. Applying our formalism to the massive high-redshift cluster XMMUJ0044.0-2-33, we find that its existence is consistent with $f_{\mathrm{NL}}=0$, although the conclusion is sensitive to the assumed values of the survey area and ${\sigma }_8$. We also discuss the convergence of the extreme-value distribution to one of the three possible asymptotic forms, and argue that the convergence is insensitive to the presence of non-Gaussianity.

A model based on $SU(3{)}_C\times SU(2{)}_L\times U(1{)}_Y\times SU(2{)}_N$ has recently been proposed, where the $SU(2{)}_N$ vector gauge bosons are neutral, so that a vector dark-matter candidate is possible and constrained by data to be less than about 1 TeV. We explore further implications of this model, including a detailed study of its Higgs sector. We improve on its dark-matter phenomenology, as well as its discovery reach at the Large Hadron Collider.

The form factors of weak decays of the $B$ meson to orbitally excited scalar, axial vector, and tensor light mesons are calculated in the framework of the QCD-motivated relativistic quark model based on the quasipotential approach. Relativistic effects are systematically taken into account. The form factors are expressed through the overlap integrals of the meson wave functions, and their dependence on the momentum transfer is self-consistently determined in the whole kinematical range. On this basis semileptonic and two-body nonleptonic $B$ decay rates to orbitally excited light mesons are calculated. Good agreement of the obtained predictions with available experimental data is found.

We consider flat Friedmann-Lemaître-Robertson-Walker cosmological models in the framework of general scalar-tensor theories of gravity with arbitrary coupling functions, set in the Jordan frame, in the cosmological epoch when the energy density of the ordinary dust matter dominates over the energy density of the scalar potential. Motivated by cosmological observations, we apply an approximation scheme in the regime close to the so-called limit of general relativity. The ensuing nonlinear approximate equations for the scalar field and the Hubble parameter can be solved analytically in cosmological time. This allows us to distinguish the theories with solutions that asymptotically converge to general relativity and draw some implications about the cosmological dynamics near this limit.

The collision-free Boltzmann equation is used in the context of brane-$f(R)$ gravity to derive the virial theorem. It is shown that the virial mass is proportional to certain geometrical terms appearing in the Einstein field equations and contributes to gravitational energy and that such a geometric mass can be attributed to the virial mass discrepancy in a cluster of galaxies. In addition, the galaxy rotation curves are studied by utilizing the concept of conformal symmetry and notion of conformal Killing symmetry. The field equations may then be obtained in an exact parametric form in terms of the parameter representing the conformal factor. This provides the possibility of studying the behavior of the angular velocity of a test particle moving in a stable circular orbit. The tangential velocity can be derived as a function of the conformal factor and integration constants, resulting in a constant value at large radial distances. Relevant phenomena such as the deflection of light passing through a region where the rotation curves are flat and the radar echo delay are also studied.

We perform the coupling of the scalar, Maxwell, and Yang-Mills fields as well as the cosmological constant to BF gravity with Immirzi parameter. The proposed action principles employ auxiliary fields in order to keep a polynomial dependence on the $B$ fields. By handling the equations of motion for the $B$ field and for the auxiliary fields, these latter can be expressed in terms of the physical fields and by substituting these expressions into the original action principles we recover the first-order (Holst) and second-order actions for gravity coupled to the physical matter fields. We consider these results a relevant step towards the understanding of the coupling of matter fields to gravity in the theoretical framework of $BF$ theory.

We construct gravitational dynamics for Finsler spacetimes in terms of an action integral on the unit tangent bundle. These spacetimes are generalizations of Lorentzian metric manifolds which satisfy necessary causality properties. A coupling procedure for matter fields to Finsler gravity completes our new theory that consistently becomes equivalent to Einstein gravity in the limit of metric geometry. We provide a precise geometric definition of observers and their measurements and show that the transformations, by means of which different observers communicate, form a groupoid that generalizes the usual Lorentz group. Moreover, we discuss the implementation of Finsler spacetime symmetries. We use our results to analyze a particular spacetime model that leads to Finsler geometric refinements of the linearized Schwarzschild solution.

Isocurvature perturbations naturally occur in models of inflation consisting of more than one scalar field. In this paper, we calculate the spectrum of isocurvature perturbations generated at the end of inflation for three different inflationary models consisting of two canonical scalar fields. The amount of nonadiabatic pressure present at the end of inflation can have observational consequences through the generation of vorticity and subsequently the sourcing of B-mode polarization. We compare two different definitions of isocurvature perturbations and show how these quantities evolve in different ways during inflation. Our results are calculated using the open source Pyflation numerical package which is available to download.

Dark matter which interacts through a magnetic or electric dipole moment is an interesting possibility which may help resolve the discrepancy between the DAMA annual modulation signal and the null results of other searches. In this article we examine relic density and collider constraints on such dark matter, and find that for couplings needed to explain DAMA, the thermal relic density is generically in the right ballpark to account for cosmological measurements. Collider constraints are relevant for light WIMPs, but less constraining that direct searches for masses above about 10 GeV.

The standard models of inflation predict statistically homogeneous and isotropic primordial fluctuations, which should be tested by observations. In this paper we illustrate a method to test the statistical isotropy of the mean of the cosmic microwave background temperature fluctuations in the spherical harmonic space and apply the method to the Wilkinson Microwave Anisotropy Probe seven-year observation data. A classical method to test a mean, like the simple Student’s t test, is not appropriate for this purpose because the Wilkinson Microwave Anisotropy Probe data contain anisotropic instrumental noise and suffer from the effect of the mask for the foreground emissions which breaks the statistical independence. Here we perform a band-power analysis with Monte Carlo simulations in which we take into account the anisotropic noise and the mask. We find evidence of a nonzero mean at 99.93% confidence level in a particular range of multipoles. The evidence against the zero-mean assumption as a whole is still significant at the 99% confidence level even if the fact is taken into account that we have tested multiple ranges.

In general, there can be mass differences among scalar bosons of the Higgs triplet field with the hypercharge of $Y=1$. In the Higgs triplet model, when the vacuum expectation value $v_{\Delta }$ of the triplet field is much smaller than that $v$ ($\simeq 246\mathrm{GeV}$) of the Higgs doublet field as required by the electroweak precision data, a characteristic mass spectrum $m_{H^{++}}^2-m_{H^{+}}^2\simeq m_{H^{+}}^2-m_{{\varphi }^0}^2(\equiv \xi )$ appears, where $m_{H^{++}}$, $m_{H^{+}}$, $m_{{\varphi }^0}$ are the masses of the doubly-charged ($H^{++}$), the singly-charged ($H^{+}$), and the neutral (${\varphi }^0=H^0$ or $A^0$) scalar bosons, respectively. It should be emphasized that phenomenology with $\xi \ne 0$ is drastically different from that in the case with $\xi =0$ where the doubly-charged scalar boson decays into the same-sign dilepton ${\ell }^{+}{\ell }^{+}$ or the diboson $W^{+}{W}^{+}$ depending on the size of $v_{\Delta }$. We find that, in the case of $\xi >0$, where $H^{++}$ is the heaviest, $H^{++}$ can be identified via the cascade decays such as $H^{++}\to H^{+}{W}^{+(*)}\to {\varphi }^0{W}^{+(*)}{W}^{+(*)}\to b\overline{b}{\ell }^{+}\nu {\ell }^{+}\nu$. We outline how the Higgs triplet model can be explored in such a case at the LHC. By the determination of the mass spectrum, the model can be tested and further distinguished from the other models with doubly-charged scalar bosons.

The radion, a scalar particle associated with the radius of a compact warped extra dimension, may be the lightest new particle in this class of models. Its couplings to SM particles are proportional to the their masses, similar to the usual Higgs boson, but suppressed by a scale ${\Lambda }_r$, the radion vacuum expectation value. The main differences are the coupling to massless gauge bosons that receives contribution from the trace anomaly of the energy-momentum tensor due to the nonvanishing $\beta$ functions and the mixing with the Higgs boson arising from a nonminimal coupling to gravity parametrized by a dimensionless coefficient $\xi$. In particular, these differences can result in significant modifications of the radion phenomenology. We use current LHC data on Higgs searches to find exclusion regions on the parameters of a radion model, ${\Lambda }_r$, $\xi$ and the radion mass $m_r$. We find that, even for low values of ${\Lambda }_r$, the radion can still have a mass in the region where the Standard Model Higgs has been excluded, for a narrow range of values for the mixing parameter. Some signals at the LHC for this scenario are discussed. We also find that it is possible to hide the Higgs boson in the current searches in this model, due to a suppression of its couplings.

In the presence of a background supergravity flux, $N$ M2-branes will expand via the Myers effect into M5-branes wrapped on a fuzzy 3-sphere. In previous work the fluctuations of the M2-branes were shown to be described by the five-dimensional Yang-Mills gauge theory associated to D4-branes. We show that the Aharony-Bergman-Jafferis-Maldacena prescription for 11-dimensional momentum in terms of magnetic flux lifts to an instanton flux of the effective five-dimensional Yang-Mills theory on the sphere, giving an $M$-theory interpretation for these instantons.

We explore the effects of collective neutrino flavor oscillations due to neutrino-neutrino interactions on the neutrino heating behind a stalled core-collapse supernova shock. We carry out axisymmetric (two-dimensional) radiation-hydrodynamic core-collapse supernova simulations, tracking the first 400 ms of the post-core-bounce evolution in $11.2\mathrm{\text{−}}{M}_{\odot }$ and $15\mathrm{\text{−}}{M}_{\odot }$ progenitor stars. Using inputs from these two-dimensional simulations, we perform neutrino flavor oscillation calculations in multienergy single-angle and multiangle single-energy approximations. Our results show that flavor conversions do not set in until close to or outside the stalled shock, enhancing heating by not more than a few percent in the most optimistic case. Consequently, we conclude that the postbounce preexplosion dynamics of standard core-collapse supernovae remains unaffected by neutrino oscillations. Multiangle effects in regions of high electron density can further inhibit collective oscillations, strengthening our conclusion.

Using the main result of a companion paper, in which the binding energy of a circular-orbit nonspinning compact binary system is computed at leading-order beyond the test-particle approximation, the exact expression of the effective-one-body (EOB) metric component $g_{tt}^{\mathrm{eff}}$ is obtained through first order in the mass ratio. Combining these results with the recent gravitational self-force calculation of the periastron advance for circular orbits in the Schwarzschild geometry, the EOB metric component $g_{rr}^{\mathrm{eff}}$ is also determined at linear order in the mass ratio. These results assume that the mapping between the real and effective Hamiltonians at the second and third post-Newtonian (PN) orders holds at all PN orders. Our findings also confirm the advantage of resumming the PN dynamics around the test-particle limit if the goal is to obtain a flexible model that can smoothly connect the test-mass and equal-mass limits.

The magnetic moments and transition magnetic moments of the ground-state baryons are analyzed in an expansion in $1/N_c$, $SU(3)$ flavor symmetry breaking and isospin symmetry breaking. There is clear evidence in the experimental data for the hierarchy of magnetic moments of the combined expansion in $1/N_c$ and flavor breaking. $SU(3)$ breaking in the magnetic moments is expected to be enhanced relative to that of other hadronic observables, and significant $SU(3)$ breaking is found.

We show that a quantized ideal fluid will generally exhibit a small but nonzero viscosity due to the backreaction of quantum sound waves on the background. We use an effective field theory expansion to estimate this viscosity to leading order in perturbation theory. We discuss our results and whether this estimate can be used to obtain a more model-independent estimate of the “quantum bound” on the viscosity of physical systems.