Within the effective field theory of inflation, an initialization of the classical dynamics of the inflaton with approximate equipartition between the kinetic and potential energy of the inflaton leads to a brief fast roll stage that precedes the slow roll regime. The fast roll stage leads to an attractive potential in the wave equations for the mode functions of curvature and tensor perturbations. The evolution of the inflationary perturbations is equivalent to the scattering by this potential and a useful dictionary between the scattering data and observables is established. Implementing methods from scattering theory we prove that this attractive potential leads to a suppression of the quadrupole moment for CMB and $B$-mode angular power spectra. The scale of the potential is determined by the Hubble parameter during slow roll. Within the effective field theory of inflation at the grand unification (GUT) energy scale we find that if inflation lasts a total number of e-folds $N_{\mathrm{tot}}\sim 59$, there is a 10%–20% suppression of the CMB quadrupole and about 2%–4% suppression of the tensor quadrupole. The suppression of higher multipoles is smaller, falling off as $1/l^2$. The suppression is much smaller for $N_{\mathrm{tot}}>59$, therefore if the observable suppression originates in the fast roll stage, there is the upper bound $N_{\mathrm{tot}}\sim 59$.

We investigate the issue of initial conditions of curvature and tensor perturbations at the beginning of slow roll inflation and their effect on the power spectra. Renormalizability and small backreaction constrain the high $k$ behavior of the Bogoliubov coefficients that define these initial conditions. We introduce a transfer function $D(k)$ which encodes the effect of generic initial conditions on the power spectra. The constraint from renormalizability and small backreaction entails that $D(k)\lesssim {\mu }^2/k^2$ for large $k$, implying that observable effects from initial conditions are more prominent in the low multipoles. This behavior affects the CMB quadrupole by the observed amount $\sim 10\%–20\%$ when $\mu$ is of the order of the energy scale of inflation. The effects on high $l$-multipoles are suppressed by a factor $\sim 1/l^2$ due to the falloff of $D(k)$ for large wave vectors $k$. We show that the determination of generic initial conditions for the fluctuations is equivalent to the scattering problem by a potential $\mathcal{V}(\eta )$ localized just prior to the slow roll stage. Such potential leads to a transfer function $D(k)$ which automatically obeys the renormalizability and small backreaction constraints. We find that an attractive potential $\mathcal{V}(\eta )$ yields a suppression of the lower CMB multipoles. Both for curvature and tensor modes, the quadrupole suppression depends only on the energy scale of $\mathcal{V}(\eta )$, and on the time interval where $\mathcal{V}(\eta )$ is nonzero. A suppression of the quadrupole for curvature perturbations consistent with the data is obtained when the scale of the potential is of the order of $k_Q^2$ where $k_Q$ is the wave vector whose physical wavelength is the Hubble radius today.

We analyze the data of the TAMA300 detector to search for gravitational waves from inspiraling compact star binaries with masses of the component stars in the range $1M_{\odot }–3M_{\odot }$. In this analysis, 2705 hours of data, taken during the years 2000–2004, are used for the event search. We combine the results of different observation runs, and obtain a single upper limit on the rate of the coalescence of compact binaries in our Galaxy of 20 per year at a 90% confidence level. In this upper limit, the effects of various systematic errors such as the uncertainty of the background estimation and the calibration of the detector’s sensitivity are included.

The recent measurements by CLEO for the inclusive $J/\Psi$ and $\Psi (2S)$ production in ${\rm Y}(1S)$ decay and our previous calculation are analyzed. The $J/\Psi$ momentum spectrum and the production ratio of $\Psi (2S)$ versus $J/\Psi$ favor ${\rm Y}\to J/\Psi (\Psi (2S))+c\overline{c}g$ as the dominant contribution. We point out that the differences between the experimental data and our previous results are mainly originated from the setting of the parameter charm quark mass. Encouraged by this result, we investigate the associate strange particle enhancement as a probe for the open charm particles in ${\rm Y}\to J/\Psi (\Psi (2S))+c\overline{c}g$.

We show that the extension of the approximate custodial $SU(2{)}_{L+R}$ global symmetry to all the Yukawa interactions of the standard model Lagrangian implies the introduction of sterile right-handed neutrinos and the seesaw mechanism in this sector. In this framework, the observed quark and lepton masses may be interpreted as an effect of physics beyond the standard model. The mechanism used for breaking this symmetry in the Yukawa sector could be different from the one at work in the vector boson sector. We give three model independent examples of these mechanisms.

The scalar contributions to the radiative decays of light vector mesons into a pair of neutral pseudoscalars, $V\to P^0{P}^0\gamma$, are studied within the framework of the linear sigma model. This model has the advantage of incorporating not only the scalar resonances in an explicit way but also the constraints required by chiral symmetry. The experimental data on $\varphi \to {\pi }^0{\pi }^0\gamma$, $\varphi \to {\pi }^0\eta \gamma$, $\rho \to {\pi }^0{\pi }^0\gamma$, and $\omega \to {\pi }^0{\pi }^0\gamma$ are satisfactorily accommodated in our framework. Theoretical predictions for $\varphi \to K^0{\overline{K}}^0\gamma$, $\rho \to {\pi }^0\eta \gamma$, $\omega \to {\pi }^0\eta \gamma$, and the ratio $\varphi \to f_0\gamma /a_0\gamma$ are also given.

We study the decays $B\to K^{(*)}{\ell }^{+}{\ell }^{-}$ and $B_s\to {\ell }^{+}{\ell }^{-}(\ell =e,\mu )$ in the minimal supersymmetric standard model with $R$-parity violation (RPV). From the recent measurements of $\mathcal{B}(B\to K^{(*)}{\ell }^{+}{\ell }^{-})$ and the upper limits of $\mathcal{B}(B_s\to {\ell }^{+}{\ell }^{-})$, we have derived new upper bounds on the relevant RPV coupling products, which are stronger than the existing ones. Using the constrained parameter space, we predict the RPV effects on the forward-backward asymmetries ${\mathcal{A}}_{\mathrm{FB}}(B\to K^{(*)}{\ell }^{+}{\ell }^{-})$ and the branching ratios $\mathcal{B}(B_s\to {\ell }^{+}{\ell }^{-})$. Our results of the forward-backward asymmetries agree with the recent experiment data. It is also found that $\mathcal{B}(B_s\to {\ell }^{+}{\ell }^{-})$ could be enhanced several orders by the RPV sneutrino exchange. The RPV effects on the dilepton invariant mass spectra of $B\to K^{(*)}{\ell }^{+}{\ell }^{-}$ and the normalized ${\mathcal{A}}_{\mathrm{FB}}(B\to K^{(*)}{\ell }^{+}{\ell }^{-})$ are studied in detail. Our results could be used to probe RPV effects and will correlate with searches for direct RPV signals at LHC.

Using 14M $\psi (2S)$ events collected at BESII, the branching fraction of $\psi (2S)\to {\tau }^{+}{\tau }^{-}$ is measured to be $B{r}_{\tau \tau }=(3.08\pm 0.21\pm 0.38)\times {10}^{-3}$, where the first error is statistical and the second is systematic.

We present branching fraction measurements of charged and neutral $B$ decays to $D{\pi }^{-}$, $D^{*}{\pi }^{-}$, and $“D^{**}”{\pi }^{-}$ with a missing mass method, based on a sample of $231\times {10}^6$ ${\rm Y}(4S)\to B\overline{B}$ pairs collected by the BABAR detector at the PEP-II $e^{+}{e}^{-}$ collider. One of the $B$ mesons is fully reconstructed and the other one decays to a reconstructed charged $\pi$ and a companion charmed meson identified by its recoil mass, inferred by kinematics. Here “$D^{**}$” refers to the sum of all the nonstrange charm meson states with masses in the range $2.2–2.8\mathrm{GeV}/c^2$. We measure the branching fractions: $\mathcal{B}(B^{-}\to D^0{\pi }^{-})=(4.49\pm 0.21\pm 0.23)\times {10}^{-3}$, $\mathcal{B}(B^{-}\to D^{*0}{\pi }^{-})=(5.13\pm 0.22\pm 0.28)\times {10}^{-3}$, $\mathcal{B}(B^{-}\to “D^{**0}”{\pi }^{-})=(5.50\pm 0.52\pm 1.04)\times {10}^{-3}$, $\mathcal{B}({\overline{B}}^0\to D^{+}{\pi }^{-})=(3.03\pm 0.23\pm 0.23)\times {10}^{-3}$, $\mathcal{B}({\overline{B}}^0\to D^{*+}{\pi }^{-})=(2.99\pm 0.23\pm 0.24)\times {10}^{-3}$, $\mathcal{B}({\overline{B}}^0\to “D^{**+}”{\pi }^{-})=(2.34\pm 0.65\pm 0.88)\times {10}^{-3}$, and their ratios.

We report improved measurements of $B$ to pseudoscalar-vector decays containing an $\omega$ meson in the final state. Our results are obtained from a data sample that contains $388\times {10}^6$ $B\overline{B}$ pairs accumulated at the ${\rm Y}(4S)$ resonance, with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider. We measure the following branching fractions: $\mathcal{B}(B^{+}\to \omega K^{+})=[8.1\pm 0.6(\mathrm{stat}.)\pm 0.6(\mathrm{syst}.)]\times {10}^{-6}$, $\mathcal{B}(B^{+}\to \omega {\pi }^{+})=[6.9\pm 0.6(\mathrm{stat}.)\pm 0.5(\mathrm{syst}.)]\times {10}^{-6}$, and $\mathcal{B}(B^0\to \omega K^0)=[{4.4}_{-0.7}^{+0.8}(\mathrm{stat}.)\pm 0.4(\mathrm{syst}.)]\times {10}^{-6}$. The partial width ratio $\frac{\Gamma (B^{+}\to \omega K^{+})}{\Gamma (B^0\to \omega K^0)}=1.7\pm 0.3(\mathrm{stat}.)\pm 0.1(\mathrm{sys}.)$. We also set the 90% confidence level upper limit $\mathcal{B}(B^0\to \omega {\pi }^0)<2.0\times {10}^{-6}$. In addition, we obtain the partial rate asymmetries ${\mathcal{A}}_{CP}={0.05}_{-0.07}^{+0.08}(\mathrm{stat}.)\pm 0.01(\mathrm{syst}.)$ for $B^{+}\to \omega K^{+}$, and ${\mathcal{A}}_{CP}=-0.02\pm 0.09(\mathrm{stat}.)\pm 0.01(\mathrm{syst}.)$ for $B^{+}\to \omega {\pi }^{+}$.

The $w-w^{\prime }$ plane, defined by the equation of state parameter for the dark energy and its derivative with respect to the logarithm of the scale factor, is useful to the study of classifying the dynamical dark energy models. In this note, we examine the evolving behavior of the two-field quintom models with $w$ crossing the $w=-1$ barrier in the $w-w^{\prime }$ plane. We find that these models can be divided into two categories, type A quintom in which $w$ changes from $>-1$ to $<-1$ and type B quintom in which $w$ changes from $<-1$ to $>-1$ as the universe expands.

Scenarios of large extra dimensions have enhanced the importance for the study of black holes in higher dimensions. In this paper, we analyze an axisymmetric system of two black holes. Specifically, the Bowen-York method is generalized for higher dimensions in order to calculate the initial data for head-on collision of two equal-mass black holes. Then, the initial data are evolved adopting the close-slow approximation to study gravitational waves emitted during the collision. We derive an empirical formula for radiation efficiency, which depends weakly on the dimensionality. Possible implications of our results for the black hole formation in particle colliders are discussed.

Using Killing-Yano symmetries, we construct conserved charges of spacetimes that asymptotically approach to the flat or anti-de Sitter spaces only in certain directions. In $D$ dimensions, this allows one to define gravitational charges (such as mass and angular momenta densities) of $p$-dimensional branes/solitons or any other extended objects that curve the transverse space into an asymptotically flat or AdS one. Our construction answers the question of what kind of charges the antisymmetric Killing-Yano tensors lead to.

Yang-Mills (YM) theory with flavor quarks in the ${\mathrm{dS}}_4$ is studied through the dual supergravity in the ${\mathrm{AdS}}_5\times S^5$ background with nontrivial dilaton and axion. The flavor quarks are introduced by embedding a probe D7 brane. We find that the dynamical properties of YM theory in the ${\mathrm{dS}}_4$ are similar to the case of the finite temperature theory given by the 5d AdS-Schwarzschild background. In the case of ${\mathrm{dS}}_4$, however, contrary to the finite temperature case, the gauge-field condensate plays an important role on the dynamical properties of quarks. We also give the quark-antiquark potential and meson spectra to find possible quark-bound states. We arrive at the conclusion that, while the quarks are not confined in the ${\mathrm{dS}}_4$, we could find stable meson states at very small cosmological constant as expected in the present universe. However, there would be no hadrons at early universe as in the inflation era.

We perform a simulation for merger of a black hole (BH)-neutron star (NS) binary in full general relativity preparing a quasicircular state as initial condition. The BH is modeled by a moving puncture with no spin and the NS by the $\Gamma$-law equation of state with $\Gamma =2$. Corotating velocity field is assumed for the NS. The mass of the BH and the rest-mass of the NS are chosen to be $\approx 3.2M_{\odot }$ and $\approx 1.4M_{\odot }$ with relatively large radius of the NS $\approx 14\mathrm{km}$. The NS is tidally disrupted near the innermost stable orbit but $\sim 80\%$ of the material is swallowed into the BH with small disk mass $\sim 0.3M_{\odot }$ even for such small BH mass $\sim 3M_{\odot }$. The result indicates that the system of a BH and a massive disk of $\sim M_{\odot }$ is not formed from nonspinning BH-NS binaries, although a disk of mass $\sim 0.1M_{\odot }$ is a possible outcome.

The disorder parameter $⟨\mu ⟩$ for the condensation of monopoles in QCD is estimated analytically in terms of gauge invariant field-strength correlators. The continuum limit is discussed.

We investigate matter-enhanced Mikheyev-Smirnov-Wolfenstein (MSW) active-sterile neutrino conversion in the ${\nu }_e\rightleftharpoons {\nu }_s$ channel in the collapse of the iron core of a presupernova star. For values of sterile neutrino rest mass $m_s$ and vacuum mixing angle $\theta$ (specifically, $0.5\mathrm{keV}<m_s<10\mathrm{keV}$ and ${sin}^{2}2\theta >5\times {10}^{-12}$) which include those required for viable sterile neutrino dark matter, our one-zone in-fall phase collapse calculations show a significant reduction in core lepton fraction. This would result in a smaller homologous core and therefore a smaller initial shock energy, disfavoring successful shock reheating and the prospects for an explosion. However, these calculations also suggest that the MSW resonance energy can exhibit a minimum located between the center and surface of the core. In turn, this suggests a post-core-bounce mechanism to enhance neutrino transport and neutrino luminosities at the core surface and thereby augment shock reheating: (1) scattering-induced or coherent MSW ${\nu }_e\to {\nu }_s$ conversion occurs deep in the core, at the first MSW resonance, where ${\nu }_e$ energies are large ($\sim 150\mathrm{MeV}$); (2) the high energy ${\nu }_s$ stream outward at near light speed; (3) they deposit their energy when they encounter the second MSW resonance ${\nu }_s\to {\nu }_e$ just below the proto-neutron star surface.

We study the fate of a collapsing star on the brane in a generalized braneworld gravity with bulk matter. Specifically, we investigate the possibility of having a static exterior for a collapsing star in the radiative bulk scenario. Here, the nonlocal correction due to bulk matter is manifest in an induced mass that adds up to the physical mass of the star resulting in an effective mass. A Schwarzschild solution for the exterior in terms of this effective mass is obtained, which reveals that, even if the star exchanges energy with the bulk, the exterior may appear to be static to a braneworld observer located outside the collapsing region. The possible explanation of the situation from the discussion on the role of bulk matter is provided. The nature of bulk matter and the corresponding bulk geometry have also been obtained and analyzed, which gives a complete picture of both brane and bulk viewpoints.

We construct a new class of charged rotating solutions of ($n+1$)-dimensional Einstein-Born-Infeld gravity with cylindrical or toroidal horizons in the presence of cosmological constant and investigate their properties. These solutions are asymptotically (anti)-de Sitter and reduce to the solutions of Einstein-Maxwell gravity as the Born-Infeld parameters goes to infinity. We find that these solutions can represent black branes, with inner and outer event horizons, an extreme black brane or a naked singularity provided the parameters of the solutions are chosen suitably. We compute temperature, mass, angular momentum, entropy, charge and electric potential of the black brane solutions. We obtain a Smarr-type formula and show that these quantities satisfy the first law of thermodynamics. We also perform a stability analysis by computing the heat capacity and the determinant of Hessian matrix of mass of the system with infinite boundary with respect to its thermodynamic variables in both the canonical and the grand-canonical ensembles, and show that the system is thermally stable in the whole phase space. Also, we find that there exists an unstable phase when the finite size effect is taken into account.

The creation of a quantum Universe is described by a density matrix which yields an ensemble of universes with the cosmological constant limited to a bounded range ${\Lambda }_{\min }\le \Lambda \le {\Lambda }_{\max }$. The domain $\Lambda <{\Lambda }_{\min }$ is ruled out by a cosmological bootstrap requirement (the self-consistent back reaction of hot matter). The upper cutoff results from the quantum effects of vacuum energy and the conformal anomaly mediated by a special ghost-avoidance renormalization. The cutoff ${\Lambda }_{\max }$ establishes a new quantum scale—the accumulation point of an infinite sequence of garland-type instantons. The dependence of the cosmological constant range on particle phenomenology suggests a possible dynamical selection mechanism for the landscape of string vacua.