We study the neutralino sector of the left-right supersymmetric model. In addition to the possibilities available in the minimal supersymmetric model, the neutralino states can be superpartners of the $U(1{)}_{B-L}$ gauge boson, the neutral $SU(2{)}_R$ gauge boson, or of the Higgs triplets. We analyze neutralino masses and determine the parameter regions for which the lightest neutralino can be one of the new pure states. We then calculate the relic density of the dark matter for each of these states and impose the constraints coming from the $\rho$ parameter, the anomalous magnetic moment of the muon, $b\to s\gamma$, as well as general supersymmetric mass bounds. The lightest neutralino can be the bino, or the right-wino, or the neutral triplet Higgsino, all of which have different couplings to the standard model particles from the usual neutralinos. A light bino satisfies all the experimental constraints and would be the preferred dark matter candidate for light supersymmetric scalar masses, while the right-wino would be favored by intermediate supersymmetric mass scales. The neutral triplet Higgs fermion satisfies the experimental bounds only in a small region of the parameter space, for intermediate to heavy supersymmetric scalar masses.

Two-gluon radiative corrections to the $b\to c\ell {\overline{\nu }}_{\ell }$ decay width have been computed analytically as an expansion in terms of $\frac{m_c}{m_b}\ll 1$ in the kinematical limit of zero lepton invariant mass. The obtained results match smoothly with a previously known expansion around $(1-\frac{m_c}{m_b})\ll 1$. Together they describe the process $b\to c\ell {\overline{\nu }}_{\ell }$ for all mass ratios $\frac{m_c}{m_b}$.

Even if quark and lepton masses are not uniquely predicted by the fundamental theory, as may be the case in the string theory landscape, nevertheless their pattern may reveal features of the underlying theory. We use statistical techniques to show that the observed masses appear to be representative of a scale-invariant distribution, $\rho (m)\sim 1/m$. If we extend this distribution to include all the Yukawa couplings, we show that the resulting Cabibbo-Kobayashi-Maskawa matrix elements typically show a hierarchical pattern similar to observations. The Jarlskog invariant measuring the amount of $CP$ violation is also well reproduced in magnitude. We also apply this framework to neutrinos using the seesaw mechanism. The neutrino results are ambiguous, with the observed pattern being statistically allowed even though the framework does not provide a natural explanation for the observed two large mixing angles. Our framework highly favors a normal hierarchy of neutrino masses. We also are able to make statistical predictions in the neutrino sector when we specialize to situations consistent with the known mass differences and two large mixing angles. Within our framework, we show that with 95% confidence the presently unmeasured Maki-Nakagawa-Sakata mixing angle $\sin {\theta }_{13}$ is larger than 0.04 and typically of order 0.1. The leptonic Jarlskog invariant is found to be typically of order ${10}^{-2}$ and the magnitude of the effective Majorana mass $m_{ee}$ is typically of order 0.001 eV.

We present a new analysis of nonuniversal and flavor changing nonstandard neutrino interactions (NSI) in ${\nu }_{e}e$ or ${\overline{\nu }}_{e}e$ scattering. Our global analysis of these processes includes all relevant experiments, such as the most recent MUNU measurement from reactor neutrinos, both in the context of the standard model as well as extensions where NSI are present. We also compare our constraints on nonuniversal and flavor changing NSI with results from previous analyses. We stress the importance of combining neutrino and antineutrino data in the resulting constraints on electroweak parameters, and the important role that future low-energy solar neutrino experiments can play in improving existing sensitivities.

A braneworld model for neutrino dark energy (DE) is presented. We consider a five-dimensional two-branes setup with a bulk scalar field motivated by supergravity. Its low-energy effective theory is derived with a moduli space approximation. The position of the two branes are parametrized by two scalar degrees of freedom (moduli). After detuning the brane tensions a classical potential for the moduli is generated. This potential is unstable for ${\mathrm{dS}}_4$ branes and we suggest to consider as a stabilizing contribution the Casimir energy of bulk fields. In particular we add a massive spinor (neutrino) field in the bulk and then evaluate the Casimir contribution of the bulk neutrino with the help of zeta function regularization techniques. We construct an explicit form of the $4D$ neutrino mass as function of the two moduli. To recover the correct DE scale for the moduli potential the usual cosmological constant fine-tuning is necessary, but, once accepted, this model suggests a stronger connection between DE and neutrino physics.

This paper deals with energy densities of scalar, massless quantum fields propagating on given, static, spherically symmetric, horizon-free spacetimes, such as these of spherical stars. The outer part of the spacetimes is assumed to be described by Schwarzschild metric, while the inner, matter containing part, which begins at the distance $\ell$ from the horizon of the Schwarzschild spacetime (measured along the spacelike radial geodesic on the surface of constant time on the Schwarzschild spacetime) is left unspecified. We shall put bounds on the ground-state expectation values of locally constructed (that is: by point-splitting and subtraction of the Hadamard singular part) energy-density operators $\rho (t,\overrightarrow{x})$, localized in the outer region. These bounds, which are derived from the so-called quantum energy inequalities, limit in absolute the difference between the energy density of ground states and the energy density of the Boulware state (the ground state for Schwarzschild spacetime). The sharpness of the bound from below depends critically on the distance $\ell$, but not on the details of internal geometry of the objects. In the limit of small $\ell$, we prove that the energy densities of ground states are greater or equal to the Boulware level.

In this paper, we investigate a kind of special quintom model, which is made of a quintessence field ${\varphi }_1$ and a phantom field ${\varphi }_2$, and the potential function has the form of $V({\varphi }_1^2-{\varphi }_2^2)$. This kind of quintom field can be separated into two kinds: the hessence model, which has the state of ${\varphi }_1^2>{\varphi }_2^2$, and the hantom model with the state ${\varphi }_1^2<{\varphi }_2^2$. We discuss the evolution of these models in the $\omega \mathrm{\text{−}}{\omega }^{\prime }$ plane ($\omega$ is the state equation of the dark energy, and ${\omega }^{\prime }$ is its time derivative in units of Hubble time), and find that according to $\omega >-1$ or $<-1$, and the potential of the quintom being climbed up or rolled down, the $\omega \mathrm{\text{−}}{\omega }^{\prime }$ plane can be divided into four parts. The late time attractor solution, if existing, is always quintessencelike or $\Lambda$-like for hessence field, so the big rip does not exist. But for hantom field, its late time attractor solution can be phantomlike or $\Lambda$-like, and sometimes, the big rip is unavoidable. Then we consider two special cases: one is the hessence field with an exponential potential, and the other is with a power law potential. We investigate their evolution in the $\omega \mathrm{\text{−}}{\omega }^{\prime }$ plane. We also develop a theoretical method of constructing the hessence potential function directly from the effective equation-of-state function $\omega (z)$. We apply our method to five kinds of parametrizations of equation-of-state parameter, where $\omega$ crossing $-1$ can exist, and find they all can be realized. At last, we discuss the evolution of the perturbations of the quintom field, and find the perturbations of the quintom ${\delta }_Q$ and the metric $\Phi$ are all finite even at the state of $\omega =-1$ and ${\omega }^{\prime }\ne 0$.

We carry out a theoretical and Monte Carlo study on the $J/\psi$ decays into $\omega \pi \pi$ and $K\overline{K}\pi$ through intermediate subthreshold $\rho$ meson by using SU(3)-symmetric Lagrangian approach. It is found that the subthreshold $\rho$ contribution is not negligible and may have significant influence on partial wave analysis of resonances in these channels, especially near the $\omega \pi$ and $K\overline{K}$ thresholds.

We present the Taylor expansion coefficients of the pressure in quark number chemical potential ${\mu }_0={\mu }_B/3={\mu }_u={\mu }_d$, for the strongly interacting matter as described by the Polyakov-Nambu-Jona-Lasinio (PNJL) model for two light degenerate flavors of quarks $u$ and $d$. The expansion has been done up to eighth order in ${\mu }_0$, and the results are consistent with recent estimates from Lattice. We have further obtained the specific heat $C_V$, squared speed of sound $v_s^2$, and the conformal measure $\mathcal{C}$.

We calculate the self-energies and the spectral densities of longitudinal and transverse gluons at zero temperature in color-superconducting quark matter in the color-flavor-locked phase. We find a collective excitation, a plasmon, at energies smaller than two times the gap parameter and momenta smaller than about eight times the gap. The dispersion relation of this mode exhibits a minimum at some nonzero value of momentum, indicating a van Hove singularity.

We study the spectrum of light plasmons in the (gapped and gapless) two-flavor color superconducting phases and its connection with the chromomagnetic instabilities and the structure of the ground state. It is revealed that the chromomagnetic instabilities in the 4th–7th and 8th gluonic channels correspond to two very different plasmon spectra. These spectra lead us to the unequivocal conclusion about the existence of gluonic condensates (some of which can be spatially inhomogeneous) in the ground state. We also argue that spatially inhomogeneous gluonic condensates should exist in the three-flavor quark matter with the values of the mass of a strange quark corresponding to the gapless color-flavor locked state.

We study the effect of resumming large logarithms in the determination of the bottom quark mass through a nonrelativistic sum rule analysis. Our result is complete at next-to-leading-logarithmic accuracy and includes some known contributions at next-to-next-to-leading logarithmic accuracy. Compared to finite order computations, the reliability of the theoretical evaluation is greatly improved, resulting in a substantially reduced scale dependence and a faster convergent perturbative series. This allows us to significantly improve over previous determinations of the $\overline{\mathrm{MS}}$ bottom quark mass, $\overline{m_b}$, from nonrelativistic sum rules. Our final figure reads $\overline{m_b}(\overline{m_b})=4.19\pm 0.06\mathrm{GeV}$.

We measure the branching fraction of the top quark to longitudinally and right-handed polarized $W$ bosons, $F_0$ and $F_{+}$, using approximately $200{\mathrm{pb}}^{-1}$ of $\overline{p}p$ collisions collected by the CDF II detector. We analyze two quantities sensitive to the $W$ helicity: the invariant mass of the charged lepton and the bottom-quark jet in the decay $t\to Wb\to \ell \nu b$ (where $\ell =e$ or $\mu$), and the transverse momentum of the charged lepton. Constrained fits yield $F_0={0.74}_{-0.34}^{+0.22}$, and $F_{+}<0.27$ at the 95% confidence level. These measurements are consistent with the standard model predictions.

In Brans-Dicke theory of gravity, we explain how the extra constant value in the formula for rotation velocities of stars in a galactic halo can be obtained due to the global monopole field. We argue on a few points of the preceding Comment and discuss improvement of our model.

The recent paper by Lee and Lee [Phys. Rev. D 69, 127502 (2004)] may strongly leave the impression that astronomers have established that the rotation curves of spiral galaxies are flat. We show that the old paradigm of flat rotation curves lacks, today, any observational support and following it at face value leads to intrinsically flawed alternatives to the standard dark matter scenario. On the other hand, we claim that the rich systematics of spiral galaxy rotation curves, which reveals, in the standard Newtonian gravity framework, the phenomenon of dark matter, in alternative scenarios, works as a unique benchmark.

We derive and solve the black hole attractor conditions of $N=8$ supergravity by finding the critical points of the corresponding black hole potential. This is achieved by a simple generalization of the special geometry symplectic structure to all extended supergravities with $N>2$. There are two classes of solutions for regular black holes, one for $1/8$ BPS ones and one for the non-BPS. We discuss the solutions of the moduli at the horizon for BPS attractors using $N=2$ language. An interpretation of some of these results in $N=2$, STU black hole context helps to clarify the general features of the black hole attractors.

In the harmonic description of general relativity, the principal part of Einstein’s equations reduces to 10 curved space wave equations for the components of the space-time metric. We present theorems regarding the stability of several evolution-boundary algorithms for such equations when treated in second order differential form. The theorems apply to a model black hole space-time consisting of a spacelike inner boundary excising the singularity, a timelike outer boundary and a horizon in between. These algorithms are implemented as stable, convergent numerical codes and their performance is compared in a 2-dimensional excision problem.

We examine the LEP limits for the $Zh\to Z+b$’s final state and find that the excess of observed events for $m_h\sim 100\mathrm{GeV}$ correlates well with there being an $m_h\sim 100\mathrm{GeV}$ Higgs boson with SM-like $ZZh$ coupling that decays partly via $h\to b\overline{b}+{\tau }^{+}{\tau }^{-}$ [with $B(h\to b\overline{b})\sim 0.08$] but dominantly via $h\to aa$ [with $B(h\to aa)\sim 0.9$], where $m_a<2m_b$ so that $a\to {\tau }^{+}{\tau }^{-}$ (or light quarks and gluons) decays are dominant. This type of scenario is precisely that predicted in the Next-to-Minimal Supersymmetric Model for parameter choices yielding the lowest possible fine-tuning.

We briefly summarize and update a class of inflationary models from the early eighties based on a quartic (Coleman-Weinberg) potential for a gauge singlet scalar (inflaton) field. For vacuum energy scales comparable to the grand unification scale, the scalar spectral index $n_s\simeq 0.94–0.97$, in very good agreement with the WMAP 3-year results. The tensor-to-scalar ratio $r\lesssim 0.14$ while $\alpha \equiv \mathrm{d}{n}_s/\mathrm{d}\ln k$ is $\simeq -{10}^{-3}$. An $SO(10)$ version naturally explains the observed baryon asymmetry via nonthermal leptogenesis.

We study the effect of including a Bhatnagar-Gross-Krook (BGK) collisional kernel on the collective modes of a QCD plasma which has a hard-particle distribution function which is anisotropic in momentum space. We calculate dispersion relations for both the stable and unstable modes and show that the addition of hard-particle collisions slows the rate of growth of QCD plasma unstable modes. We also show that for any anisotropy there is an upper limit on the collisional frequency beyond which no instabilities exist. Estimating a realistic value for the collisional frequency for ${\alpha }_s\sim 0.2–0.4$ we find that for the large-anisotropy case which is relevant for the initial state of matter generated by free streaming in heavy-ion collisions that the collisional frequency is below this critical value.