The next decade will bring massive new data sets from experiments of the direct detection of weakly interacting massive particle dark matter. Mapping the data sets to the particle-physics properties of dark matter is complicated not only by the considerable uncertainties in the dark-matter model, but by its poorly constrained local distribution function (the “astrophysics” of dark matter). I propose a shift in how to think about direct-detection data analysis. I show that by treating the astrophysical and particle-physics uncertainties of dark matter on equal footing, and by incorporating a combination of data sets into the analysis, one may recover both the particle physics and astrophysics of dark matter. Not only does such an approach yield more accurate estimates of dark-matter properties, but it may illuminate how dark matter coevolves with galaxies.

We consider the vacuum expectation value of Wilson loop operators by studying the behavior of string probes in solutions of type-IIB string theory generated by $N_c$ $D5$-branes wrapped on an $S^2$ internal manifold. In particular, we focus on solutions to the background equations that are dual to field theories with a walking gauge coupling as well as for flavored systems. We present in detail our walking solution and emphasize various general aspects of the procedure to study Wilson loops using string duals. We discuss the special features that the strings show when probing the region associated with the walking of the field-theory coupling.

Baryons in the large $N$ limit of two-dimensional Gross-Neveu models are reconsidered. The time-dependent Dirac-Hartree-Fock approach is used to boost a baryon to any inertial frame and shown to yield the covariant energy-momentum relation. Momentum distributions are computed exactly in arbitrary frames and used to interpolate between the rest frame and the infinite momentum frame, where they are related to structure functions. Effects from the Dirac sea depend sensitively on the occupation fraction of the valence level and the bare fermion mass and do not vanish at infinite momentum. In the case of the kink baryon, they even lead to divergent quark and antiquark structure functions at $x=0$.

We compute in linearized gravity all the contributions to the gravitational effective action due to a virtual Dirac fermion, related to the conformal anomaly. This requires, in perturbation theory, the identification of the gauge-gauge-graviton vertex off mass shell, involving the correlator of the energy-momentum tensor and two vector currents ($TJJ$), which is responsible for the generation of the gauge contributions to the conformal anomaly in gravity. We also present the anomalous effective action expanded in the inverse mass of the fermion as in the Euler-Heisenberg case.

We explored the motion of test particles near slowly rotating relativistic star having a uniform luminosity. In order to derive the test particle’s equations of motion, we made use of the radiation stress-energy tensor first constructed by Miller and Lamb [3]. From the particle’s trajectory obtained through the numerical integration of the equations of motion, it is found that for sufficiently high luminosity, “suspension orbit” exists, where the test particle hovers around at uniform angular velocity in the same direction as the star’s spin. Interestingly, it turned out that the radial position of the suspension orbit was determined by the luminosity and the angular momentum of the star alone and was independent of the initial positions and the specific angular momentum of the particle. Also found is that there exist not only the radiation drag but also “radiation counter drag,” which depends on the stellar radius and the angular momentum, and it is this radiation counterdrag that makes the test particle in the suspension orbit hover around at a uniform angular velocity that is greater than that induced by the Lense-Thirring effect (i.e., general relativistic dragging of inertial frame).

We study the problem of spatially stabilizing four dimensional extremal black holes in background electric/magnetic fields. Whilst looking for stationary stable solutions describing black holes placed in external fields we find that taking a continuum limit of Denef et al.’s multicenter supersymmetric black hole solutions provides a supergravity description of such backgrounds within which a black hole can be trapped within a confined volume. This construction is realized by solving for a levitating black hole over a magnetic dipole base. We comment on how such a construction is akin to a mechanical levitron.

We compare numerical evolutions performed with the BSSNOK formulation and a conformal decomposition of a Z4-like formulation of general relativity. The important difference between the two formulations is that the Z4 formulation has a propagating Hamiltonian constraint, whereas BSSNOK has a zero-speed characteristic variable in the constraint subsystem. In spherical symmetry we evolve both puncture and neutron star initial data. We demonstrate that the propagating nature of the Z4 constraints leads to results that compare favorably with BSSNOK evolutions, especially when matter is present in the spacetime. From the point of view of implementation the new system is a simple modification of BSSNOK.

We discuss the linearization of Einstein equations in the presence of a cosmological constant, by expanding the solution for the metric around a flat Minkowski space-time. We demonstrate that one can find consistent solutions to the linearized set of equations for the metric perturbations, in the Lorentz gauge, which are not spherically symmetric, but they rather exhibit a cylindrical symmetry. We find that the components of the gravitational field satisfying the appropriate Poisson equations have the property of ensuring that a scalar potential can be constructed, in which both contributions, from ordinary matter and $\Lambda >0$, are attractive. In addition, there is a novel tensor potential, induced by the pressure density, in which the effect of the cosmological constant is repulsive. We also linearize the Schwarzschild–de Sitter exact solution of Einstein’s equations (due to a generalization of Birkhoff’s theorem) in the domain between the two horizons. We manage to transform it first to a gauge in which the 3-space metric is conformally flat and, then, make an additional coordinate transformation leading to the Lorentz gauge conditions. We compare our non-spherically symmetric solution with the linearized Schwarzschild–de Sitter metric, when the latter is transformed to the Lorentz gauge, and we find agreement. The resulting metric, however, does not acquire a proper Newtonian form in terms of the unique scalar potential that solves the corresponding Poisson equation. Nevertheless, our solution is stable, in the sense that the physical energy density is positive.

The energy-momentum and angular momentum contained in a spacelike two-surface of spherical topology are estimated by joining the two-surface to null infinity via an approximate no-incoming-radiation condition. The result is a set of gauge-invariant formulas for energy-momentum and angular momentum which should be applicable to much numerical work; it also gives estimates of the finite-size effects.

Starting from Einstein-Yang-Mills theory in higher dimensions with an instanton on a compact sphere, we dimensionally reduce to find an effective four-dimensional action describing “hilltop” inflation. Using recent CMB data, we analyze the parameter space of this model to search for viable setups. One unique feature of this class of inflationary models is that the value of the inflaton field, or alternatively, the size of the compact sphere, is stabilized dynamically during the inflationary process.

We study the detectability of the gravitational waves (GWs) from the $Q$-ball formation associated with the Affleck-Dine (AD) mechanism, taking into account both the dilution effects due to $Q$-ball domination and to finite temperature. The AD mechanism predicts the formation of nontopological solitons, $Q$-balls, from which GWs are generated. $Q$-balls with large conserved charge $Q$ can produce a large amount of GWs. On the other hand, the decay rate of such $Q$-balls is so small that they may dominate the energy density of the Universe, which implies that GWs are significantly diluted and that their frequencies are redshifted during the $Q$-ball dominated era. Thus, the detectability of the GWs associated with the formation of $Q$-balls is determined by these two competing effects. We find that there is a finite but small parameter region where such GWs may be detected by future detectors such as DECIGO or BBO, only in the case when the thermal logarithmic potential dominates the potential of the AD field. Otherwise GWs from $Q$-balls would not be detectable even by these futuristic detectors: ${\Omega }_{\mathrm{GW}}^0<{10}^{-21}$. Unfortunately, for such parameter region the present baryon asymmetry of the Universe can hardly be explained unless one fine-tunes $A$-terms in the potential. However the detection of such a GW background may give us an information about the early Universe, for example, it may suggest that the flat directions with $B-L=0$ are favored.

We calculate how the relic density of dark matter particles is altered when their annihilation is enhanced by the Sommerfeld mechanism due to a Yukawa interaction between the annihilating particles. Maintaining a dark matter abundance consistent with current observational bounds requires the normalization of the $s$-wave annihilation cross section to be decreased compared to a model without enhancement. The level of suppression depends on the specific parameters of the particle model, with the kinetic decoupling temperature having the most effect. We find that the cross section can be reduced by as much as an order of magnitude for extreme cases. We also compute the $\mu$-type distortion of the CMB energy spectrum caused by energy injection from such Sommerfeld-enhanced annihilation. Our results indicate that in the vicinity of resonances, associated with bound states, distortions can be large enough to be excluded by the upper limit $|\mu |\le 9.0\times {10}^{-5}$ found by the FIRAS (Far Infrared Absolute Spectrophotometer) instrument on the COBE (Cosmic Background Explorer) satellite.

Primordial quantum fluctuations produced by inflation are conventionally assumed to be statistically homogeneous, a consequence of translational invariance. In this paper we quantify the potentially observable effects of a small violation of translational invariance during inflation, as characterized by the presence of a preferred point, line, or plane. We explore the imprint such a violation would leave on the cosmic microwave background anisotropy, and provide explicit formulas for the expected amplitudes $⟨a_{lm}{a}_{l^{\prime }{m}^{\prime }}^{*}⟩$ of the spherical-harmonic coefficients.

The cumulative (anti)neutrino production from all core-collapse supernovae within our cosmic horizon gives rise to the diffuse supernova neutrino background (DSNB), which is on the verge of detectability. The observed flux depends on supernova physics, but also on the cosmic history of supernova explosions; currently, the cosmic supernova rate introduces a substantial ($\pm 40\%$) uncertainty, largely through its absolute normalization. However, a new class of wide-field, repeated-scan (synoptic) optical sky surveys is coming online, and will map the sky in the time domain with unprecedented depth, completeness, and dynamic range. We show that these surveys will obtain the cosmic supernova rate by direct counting, in an unbiased way and with high statistics, and thus will allow for precise predictions of the DSNB. Upcoming sky surveys will substantially reduce the uncertainties in the DSNB source history to an anticipated $\pm 5\%$ that is dominated by systematics, so that the observed high-energy flux thus will test supernova neutrino physics. The portion of the universe ($z\lesssim 1$) accessible to upcoming sky surveys includes the progenitors of a large fraction ($\simeq 87\%$) of the expected 10–26 MeV DSNB event rate. We show that precision determination of the (optically detected) cosmic supernova history will also make the DSNB into a strong probe of an extra flux of neutrinos from optically invisible supernovae, which may be unseen either due to unexpected large dust obscuration in host galaxies, or because some core-collapse events proceed directly to black hole formation and fail to give an optical outburst.

We present the QCD corrections to $R_b$ and to the $\Delta B=1$ effective Hamiltonian in models with a second Higgs field that couples to the quarks respecting the criterion of minimal flavor violation, thus belonging either to the $(\mathbf{1},\mathbf{2}{)}_{1/2}$ or to the $(\mathbf{8},\mathbf{2}{)}_{1/2}$ representation of $SU(3)\times SU(2)\times U(1)$. After the inclusion of the QCD corrections, the prediction for $R_b$ becomes practically insensitive to the choice of renormalization scheme for the top mass, which for the type-I and type-II models translates in a more robust lower bound on $\tan \beta$. The QCD-corrected determinations of $R_b$ and $\mathrm{BR}(B\to X_s\gamma )$ are used to discuss the constraints on the couplings of a (colored) charged Higgs boson to top and bottom quarks.

We discuss the interplay of $\mathrm{\text{low}}\mathrm{\text{−}}x$ physics and QCD scaling violations by extending the unified approach describing inclusive structure functions and diffractive production in ${\gamma }^{*}p$ interactions proposed in previous papers to large values of $Q^2$. We describe the procedure of extracting, from the nonperturbative model, initial conditions for the QCD evolution that respect unitarity. Assuming Regge factorization of the diffractive structure function, a similar procedure is proposed for the calculation of hard diffraction. The results are in good agreement with experimental data on the proton structure function $F_2$ and the most recent data on the reduced diffractive cross section, $x_{\mathbb{P}}{\sigma }_r^{\mathcal{D}(3)}$. Predictions for both $F_2$ and $F_L$ are presented in a wide kinematical range and compared to calculations within high-energy QCD.

We compute the $B_s\to f_0(980)$ transition form factors using light-cone QCD sum rules at leading order in the strong coupling constant, and also including an estimate of next-to-leading order corrections. We use the results to predict the branching fractions of the rare decay modes $B_s\to f_0{\ell }^{+}{\ell }^{-}$ and $B_s\to f_0\nu \overline{\nu }$, which turn out to be $\mathcal{O}({10}^{-7})$ ($B_s\to f_0(980){\ell }^{+}{\ell }^{-}$, with $\ell =e$, $\mu$), $\mathcal{O}({10}^{-8})$ ($B_s\to f_0(980){\tau }^{+}{\tau }^{-}$) and $\mathcal{O}({10}^{-6})$ ($B_s\to f_0(980)\nu \overline{\nu }$). We also predict the branching ratio of $B_s\to J/\psi f_0(980)$ decay under the factorization assumption, and discuss the role of this channel for the determination of the $B_s$ mixing phase compared to the golden mode $B_s\to J/\psi \varphi$. As a last application, we consider $D_s\to f_0$ form factors, providing a determination of the branching ratio of $D_s\to f_0{e}^{+}{\nu }_e$.

The observation that $SU(3)/SU(2)\cong S^5$ implies the existence of a particularly simple quantized topological action, or Wess-Zumino-Witten (WZW) term. This action plays an important role in anomaly cancellation in extensions of the standard model electroweak sector. A closed form is presented for the action coupled to arbitrary gauge fields. The action is shown to be equivalent to a limit of the WZW term for $SU(3)\times SU(3)/SU(3)$. By reduction of $SU(3)\times U(1)/SU(2)\times U(1)$ to $SU(2)\times U(1)/U(1)$, the construction gives a topological derivation of the WZW term for the standard model Higgs field.

Tidal-charged black hole solutions localized on a three-brane in the five-dimensional gravity scenario of Randall and Sundrum have been known for some time. The solutions have been used to study the decay, and growth, of black holes with initial mass of about 10 TeV. These studies are interesting in that certain black holes, if produced at the Large Hadron Collider, could live long enough to leave the detectors. I examine the production of tidal-charged black holes at the Large Hadron Collider and show that it is very unlikely that they will be produced during the lifetime of the accelerator.

In this paper, we continue our study of calculating the cross section by the spinor method, i.e., performing the phase space integration using the spinor method. We have focused on the case where the physical momenta are massive and in pure four dimensions. We established the framework of such a new method and presented several examples, including two real progresses: $Z^0\to l^{+}{l}^{-}H$ and $q\overline{q}\to f\overline{f}{H}^0$.