The extragalactic dark matter (DM) annihilation signal depends on the product of the clumping factor, $⟨{\delta }^2⟩$, and the velocity-weighted annihilation cross section, $\sigma v$. This “clumping factor–$\sigma v$” degeneracy can be broken by comparing DM annihilation signals from multiple sources. In particular, one can constrain the minimum DM halo mass, $M_{\min }$, which depends on the mass of the DM particles and the kinetic decoupling temperature, by comparing observations of individual DM sources to the diffuse DM annihilation signal. We demonstrate this with careful semianalytic treatments of the DM contribution to the diffuse isotropic gamma-ray background (IGRB) and compare it with two recent hints of DM from the Galactic center, namely, $\sim 130\mathrm{GeV}$ DM annihilating dominantly in the $\chi \chi \to \gamma \gamma$ channel and $(10-30)\mathrm{GeV}$ DM annihilating in the $\chi \chi \to b\overline{b}$ or $\chi \chi \to {\tau }^{+}{\tau }^{-}$ channels. We show that, even in the most conservative analysis, the Fermi IGRB measurement already provides interesting sensitivity. A more detailed analysis of the IGRB, with new Fermi IGRB measurements and modeling of astrophysical backgrounds, may be able to probe values of $M_{\text{min}}$ up to $\sim 1M_{\odot }$ for the 130 GeV candidate and $\sim {10}^{-6}{M}_{\odot }$ for the light DM candidates. Increasing the substructure content of halos by a reasonable amount would further improve these constraints.

We show that Hořava gravity can be obtained from Einstein-aether theory in the limit that the twist coupling constant goes to infinity, while holding fixed the expansion, shear and acceleration couplings. This limit helps to clarify the relation between the two theories, and allows Hořava results to be obtained from Einstein-aether ones. The limit is illustrated with several examples, including rotating black hole equations, parametrized post-Newtonian parameters, and radiation rates from binary systems.

Discovery of the Higgs boson and lack of discovery of superpartners in the first run at the LHC are both predictions of split supersymmetry with thermal dark matter. We discuss what it would take to find gluinos at hadron supercolliders, including the LHC at 14 TeV center-of-mass energy, and future $pp$ colliders at 100 TeV and 200 TeV. We generalize the discussion by reexpressing the search capacity in terms of the gluino to lightest superpartner mass ratio and apply results to other scenarios, such as gauge mediation and mirage mediation.

In this paper we study a new class of supersymmetric models that can explain a 125 GeV Higgs without fine-tuning. These models contain additional “auxiliary Higgs” fields with large tree-level quartic interaction terms (from either $D$ terms or $F$ terms) but no Yukawa couplings. These have electroweak-breaking vacuum expectation values (VEVs), and they contribute to the VEVs of the Minimal Supersymmetric Standard Model Higgs via an induced tadpole in most of the parameter space. The tadpole mechanism has been previously studied in strongly coupled models with large $D$ terms, referred to as “superconformal technicolor.” The perturbative models studied here preserve gauge coupling unification in the simplest possible way, namely that all new fields are in complete $SU(5)$ multiplets. The models are consistent with the observed properties of the 125 GeV Higgs-like boson, as well as precision electroweak constraints, and predict a rich phenomenology of new Higgs states at the weak scale. The tuning is less than 10% in most of the phenomenologically allowed parameter space. If electroweak symmetry is broken by an induced tadpole, the cubic and quartic Higgs self-couplings are significantly smaller than in the standard model.

We address the interpretation of the Landau gauge gluon propagator at finite temperature as a massive-type bosonic propagator. Using pure gauge SU(3) lattice simulations at a fixed lattice volume $\sim (6.5\mathrm{fm}{)}^3$, we compute the electric and magnetic form factors, extract a gluon mass from Yukawa-like fits, and study its temperature dependence. This is relevant both for the Debye screening at high temperature $T$ and for confinement at low $T$.

The present status of experimental studies of inelastic diffraction at the Large Hadron Collider is analyzed. The impact of the current uncertainties concerning the diffraction rate on the predicted extensive air shower development is investigated. A relation to studies of the primary composition of ultrahigh energy cosmic rays is illustrated by comparing numerical simulation results to the data of the Telescope Array experiment on the distributions of the shower maximum position.

We perform a comprehensive analysis of the role of nonperturbative (or intrinsic) charm in the nucleon, generated through Fock state expansions of the nucleon wave function involving five-quark virtual states represented by charmed mesons and baryons. We consider contributions from a variety of charmed meson-baryon states and find surprisingly dominant effects from the ${\overline{D}}^{*0}{\mathrm{\Lambda }}_c^{+}$ configuration. Particular attention is paid to the existence and persistence of high-$x$ structure for intrinsic charm, and the $x$ dependence of the $c-\overline{c}$ asymmetry predicted in meson-baryon models. We discuss how studies of charmed baryons and mesons in hadronic reactions can be used to constrain models, and outline future measurements that could further illuminate the intrinsic charm component of the nucleon.

Utilizing the full CLEO-c data sample of $818{\mathrm{pb}}^{-1}$ of $e^{+}{e}^{-}$ data taken at the $\psi (3770)$ resonance, we update our measurements of absolute hadronic branching fractions of charged and neutral $D$ mesons. We previously reported results from subsets of these data. Using a double tag technique we obtain branching fractions for three $D^0$ and six $D^{+}$ modes, including the reference branching fractions $\mathcal{B}(D^0\to K^{-}{\pi }^{+})=(3.934\pm 0.021\pm 0.061)\%$ and $\mathcal{B}(D^{+}\to K^{-}{\pi }^{+}{\pi }^{+})=(9.224\pm 0.059\pm 0.157)\%$. The uncertainties are statistical and systematic, respectively. In these measurements we include the effects of final-state radiation by allowing for additional unobserved photons in the final state, and the systematic errors include our estimates of the uncertainties of these effects. Furthermore, using an independent measurement of the luminosity, we obtain the cross sections $\sigma (e^{+}{e}^{-}\to D^0{\overline{D}}^0)=(3.607\pm 0.017\pm 0.056)\mathrm{nb}$ and $\sigma (e^{+}{e}^{-}\to D^{+}{D}^{-})=(2.882\pm 0.018\pm 0.042)\mathrm{nb}$ at a center of mass energy, $E_{\mathrm{cm}}=3774\pm 1\mathrm{MeV}$.

We investigate ${\mathit{S}}^3/{\mathbb{Z}}_n$ partition function of three-dimensional $\mathcal{N}=2$ supersymmetric field theories. In a gauge theory the partition function is the sum of the contributions of sectors specified by holonomies, and we should carefully choose the relative signs among the contributions. We argue that the factorization to holomorphic blocks is a useful criterion to determine the signs and propose a formula for them. We show that the orbifold partition function of a general nongauge theory is correctly factorized provided that we take appropriate relative signs. We also present a few examples of gauge theories. We point out that the sign factor for the orbifold partition function is closely related to a similar sign factor in the lens space index and the three-dimensional index.

We investigate the finite temperature fermionic condensate and the expectation values of the charge and current densities for a massive fermion field in a spacetime background with an arbitrary number of toroidally compactified spatial dimensions in the presence of a nonvanishing chemical potential. Periodicity conditions along compact dimensions are taken with arbitrary phases and the presence of a constant gauge field is assumed. The latter gives rise to Aharonov-Bohm-like effects on the expectation values. They are periodic functions of magnetic fluxes enclosed by compact dimensions with the period equal to the flux quantum. The current density has nonzero components along compact dimensions only. Both low- and high-temperature asymptotics of the expectation values are studied. In particular, it has been shown that at high temperatures the current density is exponentially suppressed. This behavior is in sharp contrast with the corresponding asymptotic in the case of a scalar field, where the current density linearly grows with the temperature. The features for the models in odd-dimensional spacetimes are discussed. Applications are given to cylindrical and toroidal nanotubes described within the framework of effective Dirac theory for the electronic subsystem.

Following S. Giombi and I. R. Klebanov, [J. High Energy Phys. 12 (2013) 068], we carry out one-loop tests of higher spin ${\mathrm{AdS}}_{d+1}/{\mathrm{CFT}}_d$ correspondences for $d\ge 2$. The Vasiliev theories in ${\mathrm{AdS}}_{d+1}$, which contain each integer spin once, are related to the $U(N)$ singlet sector of the $d$-dimensional CFT of $N$ free complex scalar fields; the minimal theories containing each even spin once—to the $O(N)$ singlet sector of the CFT of $N$ free real scalar fields. Using analytic continuation of higher spin zeta functions, which naturally regulate the spin sums, we calculate one-loop vacuum energies in Euclidean ${\mathrm{AdS}}_{d+1}$. In even $d$ we compare the result with the $O(N^0)$ correction to the $a$ coefficient of the Weyl anomaly; in odd $d$—with the $O(N^0)$ correction to the free energy $F$ on the $d$-dimensional sphere. For the theories of integer spins, the correction vanishes in agreement with the CFT of $N$ free complex scalars. For the minimal theories, the correction always equals the contribution of one real conformal scalar field in $d$ dimensions. As explained in Giombi and Klebanov, this result may agree with the $O(N)$ singlet sector of the theory of $N$ real scalar fields, provided the coupling constant in the higher spin theory is identified as $G_N\sim 1/(N-1)$. Our calculations in even $d$ are closely related to finding the regularized $a$ anomalies of conformal higher spin theories. In each even $d$ we identify two such theories with vanishing $a$ anomaly: a theory of all integer spins, and a theory of all even spins coupled to a complex conformal scalar. We also discuss an interacting UV fixed point in $d=5$ obtained from the free scalar theory via an irrelevant double-trace quartic interaction. This interacting large $N$ theory is dual to the Vasiliev theory in ${\mathrm{AdS}}_6$ where the bulk scalar is quantized with the alternate boundary condition.

We revisit the stability analysis of cylindrical thin-shell wormholes which have been studied in literature so far. Our approach is more systematic and in parallel to the method which is used in spherically symmetric thin-shell wormholes. The stability condition is summarized as the positivity of the second derivative of an effective potential at the equilibrium radius, i.e., $V^{\prime \prime }(a_0)>0$. This may serve as the master equation in all stability problems for the cylindrical thin-shell wormholes.

A coarse-grained version of the effective action is used to study the thermodynamics of black holes, interpolating from largest to smallest masses. The physical parameters of the black hole are linked to the running couplings by thermodynamics, and the corresponding equation of state includes quantum corrections for temperature, specific heat, and entropy. If quantum gravity becomes asymptotically safe, the state function predicts conformal scaling in the limit of small horizon area and bounds on black hole mass and temperature. A metric-based derivation for the equation of state and quantum corrections to the thermodynamical, statistical, and phenomenological definition of entropy are also given. Further implications and limitations of our study are discussed.

We present the complete analytical solution of the geodesics equations in the supersymmetric [Breckenridge-Myers-Peet-Vafa (BMPV)] spacetime J. C. Breckenridge et al. Phys. Lett. B 391, 93 (1997). We study systematically the properties of massive and massless test particle motion. We analyze the trajectories with analytical methods based on the theory of elliptic functions. Since the nature of the effective potential depends strongly on the rotation parameter $\omega$, one has to distinguish between the under-rotating case, the critical case, and the over-rotating case, as discussed by Gibbons and Herdeiro in their pioneering study G. W. Gibbons and C. A. R. Herdeiro, Classical Quantum Gravity 16, 3619 (1999). We discuss various properties that distinguish this spacetime from the classical relativistic spacetimes like Schwarzschild, Reissner-Nordström, Kerr, or Myers-Perry. The over-rotating BMPV spacetime allows, for instance, for planetary bound orbits for massive and massless particles. We also address causality violation, as analyzed in G. W. Gibbons and C. A. R. Herdeiro, Classical Quantum Gravity 16, 3619 (1999).

Fluctuations of the 21 cm brightness temperature before the formation of the first stars hold the promise of becoming a high-precision cosmological probe in the future. The growth of overdensities is very well described by perturbation theory at that epoch, and the signal can in principle be predicted to arbitrary accuracy for given cosmological parameters. Recently, Tseliakhovich and Hirata pointed out a previously neglected and important physical effect, due to the fact that baryons and cold dark matter (CDM) have supersonic relative velocities after recombination. This relative velocity suppresses the growth of matter fluctuations on scales $k\sim 10–{10}^3{\mathrm{Mpc}}^{-1}$. In addition, the amplitude of the small-scale power spectrum is modulated on the large scales over which the relative velocity varies, corresponding to $k\sim 0.005–1{\mathrm{Mpc}}^{-1}$. In this paper, the effect of the relative velocity on 21 cm brightness temperature fluctuations from redshifts $z\ge 30$ is computed. We show that the 21 cm power spectrum is affected on most scales. On small scales, the signal is typically suppressed several tens of percent, except for extremely small scales ($k\gtrsim 2000{\mathrm{Mpc}}^{-1}$) for which the fluctuations are boosted by resonant excitation of acoustic waves. On large scales, 21 cm fluctuations are enhanced due to the nonlinear dependence of the brightness temperature on the underlying gas density and temperature. The enhancement of the 21 cm power spectrum is of a few percent at $k\sim 0.1{\mathrm{Mpc}}^{-1}$ and up to tens of percent at $k\lesssim 0.005{\mathrm{Mpc}}^{-1}$, for standard $\mathrm{\Lambda }\mathrm{CDM}$ cosmology. In principle this effect allows one to probe the small-scale matter power spectrum not only through a measurement of small angular scales but also through its effect on large angular scales.

Recent observations have led to the establishment of the concordance $\mathrm{\Lambda }\mathrm{CDM}$ model for cosmology. A number of experiments are being planned to shed light on dark energy, dark matter, inflation and gravity, which are the key components of the model. To optimize and compare the reach of these surveys, several figures of merit have been proposed. They are based on either the forecasted precision on the $\mathrm{\Lambda }\mathrm{CDM}$ model and its expansion or on the expected ability to distinguish two models. We propose here another figure of merit that quantifies the capacity of future surveys to rule out the $\mathrm{\Lambda }\mathrm{CDM}$ model. It is based on a measure of the difference in volume of observable space that the future surveys will constrain with and without imposing the model. This model breaking figure of merit is easy to compute and can lead to different survey optimizations than other metrics. We illustrate its impact using a simple combination of supernovae and baryon acoustic oscillation mock observations and compare the respective merit of these probes to challenge $\mathrm{\Lambda }\mathrm{CDM}$. We discuss how this approach would impact the design of future cosmological experiments.

We calculate the additional force due to two-axion exchange acting in a sphere-disk geometry, used in experiments measuring the gradient of the Casimir force. With this result, stronger constraints on the pseudoscalar coupling constants of an axion and axion-like particles to a proton and a neutron are obtained over the wide range of axion masses from $3\times 10^{-5}$ to 1 eV. Among the three experiments with Au-Au, Au-Ni, and Ni-Ni boundary surfaces performed by means of a dynamic atomic force microscope, major improvement is achieved for the experiment with Au-Au test bodies. Here, the constraints obtained are stronger by up to a factor of 170 as compared to the previously known ones. The largest strengthening holds for the axion mass 0.3 eV.

Fermionic third generation top partners are generic in composite Higgs models. They are likely to decay into third generation quarks and electroweak bosons. We propose a novel cut-and-count-style analysis in which we cross correlate the model-dependent single and model-independent pair production processes for the top partners $X_{5/3}$ and $B$. In the class of composite Higgs models we study, $X_{5/3}$ is very special as it is the lightest exotic fermion. A constraint on the mass of $X_{5/3}$ directly extends to constrains on all top partner masses. By combining jet substructure methods with conventional reconstruction techniques we show that in this kind of final state a smooth interpolation between the boosted and unboosted regime is possible. We find that a reinterpretation of existing searches can improve bounds on the parameter space of composite Higgs models. Further, at 8 TeV a combined search for $X_{5/3}$ and $B$ in the $l+\text{jets}$ final state can be more sensitive than a search involving same-sign dileptons.

We suggest top quark decays as a venue to search for light dark force carriers. The top quark is the heaviest particle in the standard model whose decays are relatively poorly measured, allowing sufficient room for exotic decay modes from new physics. A very light (GeV scale) dark gauge boson ($Z^{\prime }$) is a recently highlighted hypothetical particle that can address some astrophysical anomalies as well as the $3.6\sigma$ deviation in the muon $g-2$ measurement. We present and study a possible scenario that top quark decays as $t\to bW+Z^{\prime }s$. This is the same as the dominant top quark decay ($t\to bW$) accompanied by one or multiple dark force carriers. The $Z^{\prime }$ can be easily boosted, and it can decay into highly collimated leptons (lepton-jet) with large branching ratio. We discuss the implications for the Large Hadron Collider experiments including the analysis based on the lepton-jets.