We compute the primordial scalar, vector and tensor metric perturbations arising from quantum field inflation. Quantum field inflation takes into account the nonperturbative quantum dynamics of the inflaton consistently coupled to the dynamics of the (classical) cosmological metric. For chaotic inflation, the quantum treatment avoids the unnatural requirements of an initial state with all the energy in the zero mode. For new inflation it allows a consistent treatment of the explosive particle production due to spinodal instabilities. Quantum field inflation (under conditions that are the quantum analog of slow-roll) leads, upon evolution, to the formation of a condensate starting a regime of effective classical inflation. We compute the primordial perturbations taking the dominant quantum effects into account. The results for the scalar, vector and tensor primordial perturbations are expressed in terms of the classical inflation results. For a $N$-component field in a $O(N)$ symmetric model, adiabatic fluctuations dominate while isocurvature or entropy fluctuations are negligible. The results agree with the current Wilkinson Microwave Anisotropy Probe observations and predict corrections to the power spectrum in classical inflation. Such corrections are estimated to be of the order of $\frac{m^2}{N{H}^2}$, where $m$ is the inflaton mass and $H$ the Hubble constant at the moment of horizon crossing. An upper estimate turns to be about 4% for the cosmologically relevant scales. This quantum field treatment of inflation provides the foundations to the classical inflation and permits to compute quantum corrections to it.

The displacement noise in the test-mass mirrors of interferometric gravitational wave detectors is proportional to their elastic dissipation at the observation frequencies. In this paper, we analyze one fundamental source of dissipation in thin coatings, thermoelastic damping associated with the dissimilar thermal and elastic properties of the film and the substrate. We obtain expressions for the thermoelastic dissipation factor necessary to interpret resonant loss measurements, and for the spectral density of displacement noise imposed on a Gaussian beam reflected from the face of a coated mass. The predicted size of these effects is large enough to affect the interpretation of loss measurements, and to influence design choices in advanced gravitational wave detectors.

Motivated by the possibility of ${\mathcal{S}}_{\varphi K_S}<0$, we study the implications for the $B_s$ meson system. In a specific model that realizes ${\mathcal{S}}_{\varphi K_S}<0$ with large $s\mathrm{\text{−}}b$ mixing, right-handed dynamics, and a new CP phase, we present predictions for CP asymmetries in $B_s\to J/\psi \varphi$, $K^{+}{K}^{-}$, and $\varphi \gamma$ decays. Even if the measurement of time-dependent CP asymmetry becomes hampered by very fast $B_s$ oscillation, a finite difference between the decay rates of $B_s$ mass eigenstates may enable the studies of CP violations with untagged data samples. Thus, studies of CP violation in the $B_s$ system would remain useful for the extraction of new physics information.

We study the potential of the linear collider (LC) with $\sqrt{s}=0.5\mathrm{T}\mathrm{e}\mathrm{V}$, linac-ring type $ep$ collider ($\mathrm{L}\mathrm{C}\otimes \mathrm{L}\mathrm{H}\mathrm{C}$) with $\sqrt{s}=3.74\mathrm{T}\mathrm{e}\mathrm{V}$, and the large hadron collider (LHC) with $\sqrt{s}=14\mathrm{T}\mathrm{e}\mathrm{V}$ to search for excited neutrinos through transition magnetic type couplings with gauge bosons. The excited neutrino signal and corresponding backgrounds are studied in detail to obtain accessible mass limits and couplings for these three types of colliders.

In supersymmetric theory, the sfermion-fermion-gaugino interactions convert a sfermion into a fermion in the same chiral multiplet. The effect appears as the asymmetry between $m(j{l}^{+})$ and $m(j{l}^{-})$ distributions at the CERN Large Hadron Collider where jets ($j$) and leptons ($l^{\pm }$) arise from the cascade decay $\tilde{q}\to q{\tilde{\chi }}_2^0\to ql\tilde{l}$. Furthermore, the decay branching ratios and the charge asymmetries in $m(j{l}^{\pm })$ distributions are flavor nonuniversal due to the ${\tilde{l}}_L$ and ${\tilde{l}}_R$ mixing. When $\tan \beta$ is large, the nonuniversality between $e$ and $\mu$ becomes $O(10)\%$ level. We perform a Monte Carlo simulation for some minimal supergravity benchmark points to demonstrate the detectablity.

The cosmic-ray exotic event “Centauro-I” is reexamined. Kopenkin et al. [Phys. Rev. D 68, 052007 (2003).] have recently suggested that the original correspondence of shower clusters in the upper and the lower chambers [C. M. G. Lattes, Y. Fujimoto, and S. Hasegawa, Phys. Rep. 65, 151 (1980).] is not correct, and we confirm this suggestion. By taking into account the relative position of the upper and the lower chambers exactly, we find that the event has no upper part corresponding to the observed shower cluster in the lower chamber. Our analysis shows that showers in the shower cluster in the lower chamber are likely to have originated in a bundle of target interactions (C-jets) and that they are not a simple atmospheric family as was claimed by Kopenkin et al. The event shows peculiar characteristics quite different from commonly observed cosmic-ray events.

The magnitudes of gluon and four-quark condensates are found from the analysis of vector mesons consisting of light quarks (the families of $\rho$ and $\omega$ mesons) in the three-loops approximation. The QCD model with an infinite number of vector mesons is used to describe the function $R(s)$. This model describes well the experimental function $R(s)$. Polarization operators calculated with this model coincide with the Wilson operator expansion at large $Q^2$. The improved perturbative theory, such that the polarization operators have correct analytical properties, is used. The result is $⟨0|({\alpha }_s/\pi )G^2|0⟩=0.062\pm 0.019{\mathrm{G}\mathrm{e}\mathrm{V}}^4$. The electronic widths of $\rho (1450)$ and $\omega (1420)$ are calculated.

We study the competition between chiral symmetry restoration and two flavor color superconductivity (2SC) using a relativistic quark model with covariant nonlocal interactions in the mean field approximation. We consider two different nonlocal regulators: a Gaussian regulator and a Lorentzian regulator. We find that, although the phase diagrams are qualitatively similar to those obtained using models with local interactions, in our case the superconducting gaps at medium values of the chemical potential are larger. Consequently, we obtain that in that region the critical temperatures for the disappearance of the 2SC phase might be of the order of 100–120 MeV. We also find that, for ratios of the quark-quark and quark-antiquark couplings somewhat above the standard value $3/4$, the end point and triple point in the $T-\mu$ phase diagram meet and a phase where both the chiral and diquark condensates are non-negligible appears.

The production of $D$ mesons in the scattering of transversely polarized protons off unpolarized protons at BNL RHIC offers a clear opportunity to gain information on the Sivers gluon distribution function. $D$ production at intermediate rapidity values is dominated by the elementary $gg\to c\overline{c}$ channel; contributions from $q\overline{q}\to c\overline{c}$ $s$-channel become important only at very large values of $x_F$. In both processes there is no single spin transfer, so that the final $c$ or $\overline{c}$ quarks are not polarized. Therefore, any transverse single spin asymmetry observed for $D$’s produced in $p^{\uparrow }p$ interactions cannot originate from the Collins fragmentation mechanism, but only from the Sivers effect in the distribution functions. In particular, any sizable spin asymmetry measured in $p^{\uparrow }p\to DX$ at midrapidity values will be a direct indication of a nonzero Sivers gluon distribution function. We study the $p^{\uparrow }p\to DX$ process including intrinsic transverse motion in the parton distribution and fragmentation functions and in the elementary dynamics and show how results from RHIC could allow a measurement of ${\Delta }^N{f}_{g/p^{\uparrow }}$.

We present a measurement of the unitarity triangle angle ${\varphi }_3$ using a Dalitz plot analysis of the three-body decay of the neutral $D$ meson from the $B^{\pm }\to D^{(*)}{K}^{\pm }$ process. The method employs the interference between $D^0$ and $\overline{D^0}$ to extract both the weak and strong phases. We apply this method to a $140{\mathrm{f}\mathrm{b}}^{-1}$ data sample collected by the Belle experiment. The analysis uses the modes $B^{\pm }\to D{K}^{\pm }$ and $B^{\pm }\to D^{*}{K}^{\pm }$, $D^{*}\to D{\pi }^0$, where the neutral $D$ meson decays into $K_S{\pi }^{+}{\pi }^{-}$. We obtain 146 signal candidates for $B^{\pm }\to D{K}^{\pm }$ and 39 candidates for $B^{\pm }\to D^{*}{K}^{\pm }$. From a combined maximum likelihood fit to the $B^{\pm }\to D{K}^{\pm }$ and $B^{\pm }\to D^{*}{K}^{\pm }$ modes, we obtain ${\varphi }_3=77°\genfrac{}{}{0ex}{}{+17°}{-19°}(\mathrm{\text{stat}})\pm 13°(\mathrm{\text{syst}})\pm 11°(\mathrm{\text{model}})$. The corresponding 2 standard deviation interval is $26°<{\varphi }_3<126°$.

We examine physical features that could lead to formation of a naked singularity rather than black hole, as end state of spherical collapse. Generalizing earlier results on dust collapse to general type I matter fields, it is shown that collapse always creates black hole if shear vanishes or density is homogeneous. It follows that nonzero shear is a necessary condition for singularity to be visible to external observers, when trapped surface formation is delayed by shearing forces or inhomogeneity within the collapsing cloud.

We classify compactifications of the type IIB superstring on $\mathrm{A}\mathrm{d}{\mathrm{S}}_{\mathrm{5}}\times {\mathrm{S}}^5/\Gamma$, where $\Gamma$ is an abelian group of order $n\le 12$. Appropriate embedding of $\Gamma$ in the isometry of ${\mathrm{S}}^5$ yields both SUSY and non–SUSY chiral models that can contain the minimal SUSY standard model or the standard model. New non-SUSY three-family models with $\Gamma =Z_8$ are introduced, which lead to the right Weinberg angle for TeV trinification. These models form a small but interesting subclass of the set of ${\mathrm{S}\mathrm{U}}^n(N)$ gauge theories with bifundamental matter.

An $\ell$-pole perturbation in Schwarzschild spacetime generally falls off at late times $t$ as $t^{-2\ell -3}$. It has recently been pointed out by Karkowski, Świerczyński, and Malec, that for initial data that is of compact support, and is initially momentarily static, the late-time behavior is different, going as $t^{-2\ell -4}$. By considering the Laplace transforms of the fields, we show here why the momentarily stationary case is exceptional. We also explain, using a time-domain description, the special features of the time development in this exceptional case.

We construct a class of spherically symmetric collapse models in which a naked singularity may develop as the end state of collapse. The matter distribution considered has negative radial and tangential pressures, but the weak energy condition is obeyed throughout. The singularity forms at the center of the collapsing cloud and continues to be visible for a finite time. The duration of visibility depends on the nature of energy distribution. Hence the causal structure of the resulting singularity depends on the nature of the mass function chosen for the cloud. We present a general model in which the naked singularity formed is timelike, neither pointlike nor null. Our work represents a step toward clarifying the necessary conditions for the validity of the Cosmic Censorship Conjecture.

We calculate the current power spectrum of the gravitational waves created at the big bang (and later amplified by the different transitions during the Universe expansion) taking into account the present stage of accelerated expansion. Likewise, we determine the power spectrum in a hypothetical second dust era that would follow the present one if at some future time the dark energy, that supposedly drives the current accelerated expansion, evolved in such a way that it became dynamically equivalent to cold dark matter. The calculated power spectrums as well as the evolution of the density parameter of the waves may serve to discriminate between different phases of expansion and may help ascertain the nature of dark energy.

Measurements suggest that our universe has a substantial dark energy component. The most recent data on type Ia supernovae give a dark energy density which is in good agreement with other measurements if the dark energy is assumed to be a cosmological constant. Here we examine to what extent that data can put constraints on a more general equation of state for the dark energy.

Braneworld inflation is a phenomenology related to string theory that describes high-energy modifications to general relativistic inflation. The observable universe is a brane embedded in 5-dimensional anti de Sitter spacetime. When the 5-dimensional action is Einstein-Hilbert, we have a Randall-Sundrum type braneworld. The amplitude of tensor and scalar perturbations from inflation is strongly increased relative to the standard results, although the ratio of tensor to scalar amplitudes still obeys the standard consistency relation. If a Gauss-Bonnet term is included in the action, as a high-energy correction motivated by string theory, we show that there are important changes to the Randall-Sundrum case. We give an exact analysis of the tensor perturbations. They satisfy the same wave equation and have the same spectrum as in the Randall-Sundrum case, but the Gauss-Bonnet change to the junction conditions leads to a modified amplitude of gravitational waves. The amplitude is no longer monotonically increasing with energy scale, but decreases asymptotically after an initial rise above the standard level. Using an approximation that neglects bulk effects, we show that the amplitude of scalar perturbations has a qualitatively similar behavior to the tensor amplitude. In addition, the tensor to scalar ratio breaks the standard consistency relation.