Fierz identities follow from permutations of quark indices and thus determine which chiral multiplets of baryon fields are Pauli allowed and which are not. In a previous paper we investigate the Fierz identities of baryon fields with two light flavors and find that all bilocal fields that can be constructed from three quarks are Pauli allowed. That does not mean that all possible chiral multiplets exist; however, some chiral multiplets do not appear among structures with a given spin in the local limit, say $J=1/2$. One such chiral multiplet is the [$(\mathbf{6},\mathbf{3})\oplus (\mathbf{3},\mathbf{6})$], which is necessary for a successful chiral mixing phenomenology. In the present paper we extend those methods to three light flavors, i.e., to $S{U}_F(3)$ symmetry and explicitly construct all three necessary chiral $S{U}_L(3)\times S{U}_R(3)$ multiplets, viz. [$(\mathbf{6},\mathbf{3})\oplus (\mathbf{3},\mathbf{6})$], $[(\mathbf{3},\overline{\mathbf{3}})\oplus (\overline{\mathbf{3}},\mathbf{3})]$, and [$(\overline{\mathbf{3}},\mathbf{3})\oplus (\mathbf{3},\overline{\mathbf{3}})$] that are necessary for a phenomenologically successful chiral mixing. We complete this analysis by considering some bilocal baryon fields that are sufficient for the construction of the “missing” spin-$1/2$ baryon interpolating fields. Bilocal baryon fields have definite total angular momentum only in the local limit. The physical significance of these results lies in the fact that they show that there is no need for higher Fock space components, such as the $q^4\overline{q}$, in the baryon chiral mixing framework, for the purpose of fitting the observed axial couplings and magnetic moments: all of the sufficient “mirror components” exist as bilocal fields.

We propose new signals for the direct detection of ultralight dark matter such as the axion. Axion or axionlike particle dark matter may be thought of as a background, classical field. We consider couplings for this field which give rise to observable effects including a nuclear electric dipole moment, and axial nucleon and electron moments. These moments oscillate rapidly with frequencies accessible in the laboratory, $\sim$ kilohertz to gigahertz, given by the dark matter mass. Thus, in contrast to WIMP detection, instead of searching for the hard scattering of a single dark matter particle, we are searching for the coherent effects of the entire classical dark matter field. We calculate current bounds on such time-varying moments and consider a technique utilizing NMR methods to search for the induced spin precession. The parameter space probed by these techniques is well beyond current astrophysical limits and significantly extends laboratory probes. Spin precession is one way to search for these ultralight particles, but there may well be many new types of experiments that can search for dark matter using such time-varying moments.

We revisit the implications of naturalness and gauge unification in the minimal supersymmetric standard model. We find that precision unification of the couplings in connection with a small $\mu$ parameter requires a highly compressed gaugino pattern as it is realized in mirage mediation. Due to the small mass difference between the gluino and lightest supersymmetric particle (LSP), collider limits on the gluino mass are drastically relaxed. Without further assumptions, the relic density of the LSP is very close to the observed dark matter density due to coannihilation effects.

We study hypothetical gauge bosons that may produce dijet resonances at the LHC. Simple renormalizable models include leptophobic $Z^{\prime }$ bosons or colorons that have flavor-independent couplings and decay into a color-singlet or -octet quark-antiquark pair, respectively. We present the experimental results on dijet resonances at hadron colliders as limits in the coupling-versus-mass plane of a gauge boson associated with baryon number. This theoretical framework facilitates a direct comparison of dijet resonance searches performed at different center-of-mass energies or at different colliders.

The existence of light sterile neutrinos in the eV mass range with relatively large mixing angles with the active neutrinos has been proposed for a variety of reasons, including to improve the fit to the LSND and MiniBooNE neutrino oscillation experiments, and reactor disappearance experiments. A. E. Nelson [Phys. Rev. D 84, 053001 (2011)] showed that neutrino mixing with a heavier sterile neutrino, in the mass range between 33 eV and several GeV, could significantly affect and improve the agreement between neutrino oscillation models with light sterile neutrinos and short baseline experimental results, allowing for a new source of charge parity violation in appearance experiments and for different apparent mixing angles in appearance and disappearance experiments. However E. Kuflik, S. D. McDermott, and K. M. Zurek [Phys. Rev. D 86, 033015 (2012)], and J. Fan and P. Langacker [J. High Energy Phys. 04 (2012) 083], showed that various collider experiments, supernovae, and cosmological constraints can eliminate most of the parameter region where such a heavy sterile neutrino can have a significant effect on neutrino oscillations. In this paper we consider the effects of allowing a new light scalar in the MeV mass region, which is a potential dark matter candidate, to interact with the sterile neutrinos, and show that the resulting model is a consistent theory of neutrino oscillation anomalies and dark matter which can also potentially explain the INTEGRAL excess of 511 keV gamma rays in the central region of the galaxy.

Inclusive production cross sections of ${\pi }^{\pm }$, $K^{\pm }$ and $p/\overline{p}$ per hadronic $e^{+}{e}^{-}$ annihilation event are measured at a center-of-mass energy of 10.54 GeV, using a relatively small sample of very high quality data from the BABAR experiment at the PEP-II $B$-factory at the SLAC National Accelerator Laboratory. The drift chamber and Cherenkov detector provide clean samples of identified ${\pi }^{\pm }$, $K^{\pm }$, and $p/\overline{p}$ over a wide range of momenta. Since the center-of-mass energy is below the threshold to produce a $B\overline{B}$ pair, with $B$ a bottom-quark meson, these data represent a pure $e^{+}{e}^{-}\to q\overline{q}$ sample with four quark flavors, and are used to test QCD predictions and hadronization models. Combined with measurements at other energies, in particular at the $Z^0$ resonance, they also provide precise constraints on the scaling properties of the hadronization process over a wide energy range.

Using a sample of $1.06\times {10}^8$ $\psi (2S)$ events collected with the BESIII detector at BEPCII, the decay $\psi (2S)\to p\overline{p}\eta$ is studied. A partial wave analysis determines that the intermediate state $N(1535)$ with a mass of $1524\pm 5_{-4}^{+10}\mathrm{MeV}/c^2$ and a width of ${130}_{-24-10}^{+27+57}\mathrm{MeV}/c^2$ is dominant in the decay; the product branching fraction is determined to be $B(\psi (2S)\to N(1535)\overline{p})\times B(N(1535)\to p\eta )+\mathrm{c}.\mathrm{c}.=(5.2\pm {0.3}_{-1.2}^{+3.2})\times {10}^{-5}$. Furthermore, the branching fraction of $\psi (2S)\to p\overline{p}\eta$ is measured to be $(6.4\pm 0.2\pm 0.6)\times {10}^{-5}$. Here, the first error is statistical and the second is systematic.

I present approximate next-to-next-to-leading-order top-quark transverse momentum, $p_T$, distributions in $t$-channel single-top production. These distributions are derived from next-to-next-to-leading-logarithm soft-gluon resummation. Theoretical results for the single top as well as the single-antitop $p_T$ distributions are shown for LHC and Tevatron energies.

$N$-point correlation functions of conserved currents and weight-two scalar operators of the three-dimensional free fermion vector model are found as invariants of the higher-spin symmetry in four-dimensional AdS. These are the correlators of the unbroken Vasiliev higher-spin theory. The results extend the recent work arXiv:1210.7963 and are complementary to arXiv:1301.3123 where the correlators were computed entirely on the boundary.

We formulate a generic three-dimensional superfield higher-derivative gauge theory coupled to matter, which in certain cases reduces to the three-dimensional scalar super-QED, supersymmetric Maxwell-Chern-Simons, or Chern-Simons theories with matter. For this theory, we explicitly calculate the one-loop effective potential.

The transition probabilities describing the evolution of a neutrino with a given energy along some ray through a turbulent supernova profile are random variates unique to each ray. If the proto–neutron-star source of the neutrinos were a point, then one might expect the evolution of the turbulence would cause the flavor composition of the neutrinos to vary in time i.e. the flavor would scintillate. But in reality the proto–neutron star is not a point source—it has a size of order $\sim 10\mathrm{km}$, so the neutrinos emitted from different points at the source will each have seen different turbulence. The finite source size will reduce the correlation of the flavor transition probabilities along different trajectories and reduce the magnitude of the flavor scintillation. To determine whether the finite size of the proto–neutron star will preclude flavor scintillation, we calculate the correlation of the neutrino flavor transition probabilities through turbulent supernova profiles as a function of the separation $\delta x$ between the emission points. The correlation will depend upon the power spectrum used for the turbulence, and we consider two cases: when the power spectrum is isotropic, and the more realistic case of a power spectrum which is anisotropic on large scales and isotropic on small. Although it is dependent on a number of uncalibrated parameters, we show the supernova neutrino source is not of sufficient size to significantly blur flavor scintillation in all mixing channels when using an isotropic spectrum, and this same result holds when using an anisotropic spectrum, except when we greatly reduce the similarity of the turbulence along parallel trajectories separated by $\sim 10\mathrm{km}$ or less.

We derive analytically the asymptotic behavior of the Casimir interaction between a sphere and a plate when the distance between them, $d$, is much smaller than the radius of the sphere, $R$. The leading-order and next-to-leading-order terms are derived from the exact formula for the Casimir interaction energy. They are found to depend nontrivially on the dielectric functions of the objects. As expected, the leading-order term coincides with that derived using the proximity force approximation. Numerical results are presented when the dielectric functions are given by the plasma model or the Drude model, with the plasma frequency (for plasma and Drude models) and relaxation frequency (for Drude model) given by the conventional values used for gold metal. It is found that if plasma model is used instead of the Drude model, the error in the sum of the first two leading terms is at most 2%, while the error in ${\theta }_1$, the ratio of the next-to-leading-order term divided by $d/R$ to the leading-order term, can go up to 4.5%.

The nonminimally coupled $f(R)$ gravity model is an interesting approach to explain the late time acceleration of the Universe without introducing any exotic matter component in the energy budget of the Universe. But distinguishing such model with the concordance $\Lambda$ cold dark matter $(\Lambda \mathrm{CDM})$ model using present observational data is a serious challenge. In this paper, we address this issue using the observations related to the growth of matter over density $g(z)$ as measured by different galaxy surveys. As background cosmology is not sufficient to distinguish different dark energy models, we first find out the functional form for $f(R)$ (which is nonminimally coupled to the matter Lagrangian) that produces the similar background cosmology as in $\Lambda \mathrm{CDM}$. Subsequently we calculate the growth for the matter over density $g(z)$ for such nonminimally coupled $f(R)$ models and compare them with the $\Lambda \mathrm{CDM}$ universe. We also use the measurements of $g(z){\sigma }_8(z)$ by different galaxy surveys to reconstruct the behavior for $g(z)$ and ${\sigma }_8(z)$ for both the nonminimally coupled $f(R)$ gravity models as well as for the $\Lambda \mathrm{CDM}$. Our results show that there is a small but finite window where one can distinguish the nonminimally coupled $f(R)$ models with the concordance $\Lambda \mathrm{CDM}$.

Using an extended set of equations of state and a multiple-group multiple-code collaborative effort to generate waveforms, we improve numerical-relativity-based data-analysis estimates of the measurability of matter effects in neutron-star binaries. We vary two parameters of a parametrized piecewise-polytropic equation of state (EOS) to analyze the measurability of EOS properties, via a parameter $\Lambda$ that characterizes the quadrupole deformability of an isolated neutron star. We find that, to within the accuracy of the simulations, the departure of the waveform from point-particle (or spinless double black-hole binary) inspiral increases monotonically with $\Lambda$ and changes in the EOS that did not change $\Lambda$ are not measurable. We estimate with two methods the minimal and expected measurability of $\Lambda$ in second- and third-generation gravitational-wave detectors. The first estimate using numerical waveforms alone shows that two EOSs which vary in radius by 1.3 km are distinguishable in mergers at 100 Mpc. The second estimate relies on the construction of hybrid waveforms by matching to post-Newtonian inspiral and estimates that the same EOSs are distinguishable in mergers at 300 Mpc. We calculate systematic errors arising from numerical uncertainties and hybrid construction, and we estimate the frequency at which such effects would interfere with template-based searches.

We present Newtonian and fully general-relativistic solutions for the evolution of a spherical region of uniform interior density ${\rho }_{\mathrm{i}}(t)$, embedded in a background of uniform exterior density ${\rho }_{\mathrm{e}}(t)$. In both regions, the fluid is assumed to support pressure. In general, the expansion rates of the two regions, expressed in terms of interior and exterior Hubble parameters $H_{\mathrm{i}}(t)$ and $H_{\mathrm{e}}(t)$, respectively, are independent. We consider in detail two special cases: an object with a static boundary, $H_{\mathrm{i}}(t)=0$; and an object whose internal Hubble parameter matches that of the background, $H_{\mathrm{i}}(t)=H_{\mathrm{e}}(t)$. In the latter case, we also obtain fully general-relativistic expressions for the force required to keep a test particle at rest inside the object, and that required to keep a test particle on the moving boundary. We also derive a generalized form of the Oppenheimer-Volkov equation, valid for general time-dependent spherically symmetric systems, which may be of interest in its own right.

After discussing the various issues regarding and requirements on pure quantum gravitational observables in homogeneous-isotropic conditions, we construct a composite operator observable satisfying most of them. We also expand it to first order in the loop counting parameter and suggest it as a physical quantifier of gravitational backreaction in an initially inflating cosmology.

We describe the cosmological evolution predicted by three distinct $f(R)$ theories, with emphasis on the evolution of linear perturbations. The most promising observational tools for distinguishing $f(R)$ theories from $\Lambda \mathrm{CDM}$ are those intrinsically related to the growth of structure, such as weak lensing. At the linear level, the enhancement in the gravitational potential provided by the additional $f(R)$ “fifth force” can separate the theories, whereas at the background level they can be indistinguishable. Under the stringent constraints imposed on the models by Solar System tests and galaxy-formation criteria, we show that the relative difference between the models’ linear evolution of the lensing potential will be extremely hard to detect even with future space-based experiments such as Euclid, with a maximum value of approximately 4% for small scales. We also show the evolution of the gravitational potentials under more relaxed local constraint conditions, where the relative difference between these models and $\Lambda \mathrm{CDM}$ could prove discriminating.

We show that the observational universe may emerge classically from a de Sitter background with low-energy scale. We find, after calculating the curvature perturbation, that the resulting scenario is actually a style of the eternal inflation scenario, in which some regions will go through the slowly expanding Galilean genesis phase with the rapidly increasing energy density and become island universes, while other regions are still eternally inflating, which will make the room for more island universes to emerge.

As the technology of gravitational-wave and neutrino detectors becomes increasingly mature, a multimessenger era of astronomy is ushered in. Advanced gravitational-wave detectors are close to making a ground-breaking discovery of gravitational-wave bursts (GWBs) associated with mergers of double neutron stars (NS-NS). It is essential to study the possible electromagnetic and neutrino emission counterparts of these GWBs. Recent observations and numerical simulations suggest that at least a fraction of NS-NS mergers may leave behind a massive millisecond magnetar as the merger product. Here we show that protons accelerated in the forward shock powered by a magnetar wind pushing the ejecta launched during the merger process would interact with photons generated in the dissipating magnetar wind and emit high-energy neutrinos and photons. We estimate the typical energy and fluence of the neutrinos from such a scenario. We find that $\sim \mathrm{PeV}$ neutrinos could be emitted from the shock front as long as the ejecta could be accelerated to a relativistic speed. The diffuse neutrino flux from these events, even under the most optimistic scenarios, is too low to account for the two events announced by the IceCube Collaboration, but it is only slightly lower than the diffuse flux of GRBs, making it an important candidate for the diffuse background of $\sim \mathrm{PeV}$ neutrinos. The neutron-pion decay of these events make them a moderate contributor to the sub-TeV gamma-ray diffuse background.

In this Communication, we present a class of Brans-Dicke-like theories with a universal coupling between the scalar field and the matter Lagrangian. We show this class of theories naturally exhibits a decoupling mechanism between the scalar field and matter. As a consequence, this coupling leads to almost the same phenomenology as general relativity in the Solar System: the trajectories of massive bodies and the light propagation differ from general relativity only at the second post-Newtonian order. Deviations from general relativity are beyond present detection capabilities. However, this class of theories predicts a deviation of the gravitational redshift at a level detectable by the future ACES and STE/QUEST missions.