The recently released BICEP2 data detected the primordial B-mode polarization in the cosmic microwave background (CMB) map which strongly supports for a large tensor-to-scalar ratio, and, thus, is found to be in tension with the Planck experiment with no evidence of primordial gravitational waves. Such an observational tension, if confirmed by forthcoming measurements, would bring a theoretical challenge for the very early Universe models. To address this issue, we revisit a single field inflation model proposed by Wang et al. [Int. J. Mod. Phys. D 14, 1347 (2005)] and Feng et al. [Phys. Rev. D 68, 103511 (2003)] which includes a modulated potential. We show that this inflation model can give rise to a sizable negative running behavior for the spectral index of primordial curvature perturbation and a large tensor-to-scalar ratio. Applying these properties, our model can nicely explain the combined Planck and BICEP2 observations. To examine the validity of analytic calculations, we numerically confront the predicted temperature and B-mode power spectra with the latest CMB observations and explicitly show that our model is consistent with the current data.

The large tensor spectrum recently observed by the BICEP2 Collaboration requires a super-Planckian field variation of the inflaton in the single-field inflationary scenario. The required slow-roll parameter $\epsilon \approx 0.01$ would restrict the e-folding number to around 7 in (sub-)Planckian inflationary models. To overcome such problems, we consider a two-field scenario based on the natural assisted supersymmetric (SUSY) hybrid model {“natural SUSY hybrid inflation” [K.-Y. Choi and B. Kyae, Phys. Lett. B 706, 243 (2012)]}, which combines the SUSY hybrid and the natural inflation models. The axionic inflaton field from the natural inflation sector can admit the right values for the tensor spectrum as well as a spectral index of 0.96 with a decay constant smaller than the Planck scale, $f\lesssim M_P$. On the other hand, the vacuum energy of $2\times {10}^{16}\mathrm{GeV}$ with 50 e-folds is provided by the inflaton coming from the SUSY hybrid sector, avoiding the eta problem. These are achieved by introducing both the $U(1{)}_R$ and a shift symmetry, and employing the minimal Kähler potential.

If $R$ parity is only mildly violated, then the lightest supersymmetric particle (LSP) can be stable over cosmologically time scales and still account for the dark matter relic density. We examine the possibility of generating detectable x-ray lines from $R$-parity violating decays of keV-scale LSP dark matter to neutrino-photon pairs. Specifically, we consider scenarios in which the LSP is a light gravitino, bino, or hidden sector photino. Potential signals are discussed in the context of recent claims of an unidentified 3.5 keV x-ray line in studies of stacked galaxy clusters. We comment on the difficulties in obtaining the observed relic density for keV-scale bino or hidden photino dark matter and some possible resolutions.

For there to be a successful measurement of the 21 cm epoch of reionization (EoR) power spectrum, it is crucial that strong foreground contaminants be robustly suppressed. These foregrounds come from a variety of sources (such as Galactic synchrotron emission and extragalactic point sources), but almost all share the property of being spectrally smooth and, when viewed through the chromatic response of an interferometer, occupy a signature “wedge” region in cylindrical $k_{\perp }{k}_{\parallel }$ Fourier space. The complement of the foreground wedge is termed the “EoR window” and is expected to be mostly foreground-free, allowing clean measurements of the power spectrum. This paper is a sequel to a previous paper that established a rigorous mathematical framework for describing the foreground wedge and the EoR window. Here, we use our framework to explore statistical methods by which the EoR window can be enlarged, thereby increasing the sensitivity of a power spectrum measurement. We adapt the Feldman-Kaiser-Peacock approximation (commonly used in galaxy surveys) for 21 cm cosmology and also compare the optimal quadratic estimator to simpler estimators that ignore covariances between different Fourier modes. The optimal quadratic estimator is found to suppress foregrounds by an extra factor of $\sim {10}^5$ in power at the peripheries of the EoR window, boosting the detection of the cosmological signal from $12\sigma$ to $50\sigma$ at the midpoint of reionization in our fiducial models. If numerical issues can be finessed, decorrelation techniques allow the EoR window to be further enlarged, enabling measurements to be made deep within the foreground wedge. These techniques do not assume that foreground is Gaussian distributed, and we additionally prove that a final round of foreground subtraction can be performed after decorrelation in a way that is guaranteed to have no cosmological signal loss.

In the framework of general 3-3-1 models, we perform a global ${\chi }^2$ fit at 95% C.L. to the updated $Z$ pole observables, including new data from atomic parity violation. We found scenarios where specific realizations of 3-3-1 models are largely excluded above the current limit on the extra neutral gauge boson ($Z^{\prime }$) research at the LHC. We derive a relation between the $Z\text{−}{Z}^{\prime }$ mixing angle and the parameter $\tan (\beta )$ of the effective two-Higgs-doublet model contained into the 3-3-1 spectrum. We show that particular versions of 3-3-1 models containing particles with exotic electric charges are disfavored by the electroweak precision observables in an ample region of the parameter space.

The slowly evolving gauge coupling of gauge-fermion systems near the conformal boundary makes numerical investigations of these models challenging. We consider finite size scaling and show that in the case of 12-flavor SU(3) gauge theory this often-used technique leads to inconsistent results if the leading order scaling corrections are neglected. When the corrections are included the results become consistent not only between different operators but even when data obtained at different gauge couplings or with different lattice actions are combined. Our results indicate that the SU(3) 12-fermion system is infrared conformal with mass anomalous dimension ${\gamma }_m=0.235(15)$.

We apply the Grassmann tensor renormalization group to the lattice regularized Schwinger model with one-flavor of the Wilson fermion. We study the phase diagram in the $(\beta ,\kappa )$ plane performing a detailed analysis of the scaling behavior of the Lee-Yang zeros and the peak height of the chiral susceptibility. Our results strongly indicate that the whole range of the phase transition line starting from $(\beta ,\kappa )=(0.0,0.380665(59))$ and ending at $(\infty ,0.25)$ belongs to the two-dimensional Ising universality class similar to the free fermion case.

A procedure based on the well-known $\mathcal{K}$-matrix formalism is presented, which makes patterns in inelastic regions of low-energy scattering data considerably more transparent. It relies on the use of an empirical kernel, obtained by eliminating elastic loops from the experimental amplitude. This allows structures associated with resonances, such as locations, widths, and heights, to become visible with the naked eye. The method is illustrated with a study of the $P$-wave $K\pi$ amplitude.

We study possible multiquark contributions to the charm baryon spectrum by considering higher order Fock space components. For this purpose we perform two different calculations. In a first approach we do a coupled-channel calculation of the $ND$ system looking for molecular states. In a second step we allow for the coupling to a heavy baryon–light meson two-hadron system looking for compact exotic five-quark structures. Both calculations have been done within the framework of a chiral constituent quark model. The model, tuned in the description of the baryon and meson spectra as well as the $NN$ interaction, provides parameter-free predictions for charm $+1$ molecular or compact two-hadron systems. Unlike the $N\overline{D}$ system, no sharp quark-Pauli effects are found. However, the existence of different two-hadron thresholds for the five-quark system will make the coupled-channel dynamics relevant. Only a few channels are candidates to lodge molecular or compact hadrons with a five-quark structure, being specially relevant the $(T)J^P=(0)1/2^{-}$ and $(T)J^P=(2)5/2^{-}$ channels. The identification of molecular states and/or compact hadrons with multiquark components either with or without exotic quantum numbers is a challenge of different collaborations like PANDA, LHCb, ExHIC or J-PARC.

We present results for the complete $\mathrm{NNLL}+\mathrm{NLO}$ ($\sim {\alpha }_s$) 1-jettiness (${\tau }_1$) event shape distribution for single jet ($J$) production in electron-nucleus ($N_A$) collisions $e^{-}+N_A\to e^{-}+J+X$, in the deep inelastic scattering (DIS) region where the hard scale is set by the jet transverse momentum $P_{J_T}$. These results cover the entire ${\tau }_1$ spectrum including the resummation (${\tau }_1\ll P_{J_T}$) and fixed-order (${\tau }_1\sim P_{J_T}$) perturbative QCD regions. They incorporate nonperturbative soft radiation effects, the anti-$k_T$ jet algorithm in the fixed-order calculation, and a smooth matching between the resummation and fixed-order perturbative QCD regions. The matching smoothly connects the spectrum in the resummation region, which can be computed without reference to an external jet algorithm, and the fixed-order region where an explicit jet algorithm must be specified. Our code, used for generating the numerical results, is flexible enough to incorporate different jet algorithms for the fixed-order calculation. We also perform a jet-shape analysis, defined within the 1-jettiness framework, which allows one to control the amount of radiation included in the definition of the final state jet. This formalism can allow for detailed studies of jet energy-loss mechanisms and nuclear medium effects. The analysis presented here can be used for precision studies of QCD and as a probe of nuclear dynamics using data collected at HERA and in proposed future electron-ion colliders such as the EIC and the LHeC.

Inhomogeneous chiral-symmetry breaking phases at nonvanishing chemical potential and temperature are studied within a two-flavor quark-meson model in the chiral limit. The analysis is performed beyond the standard mean-field approximation by taking into account the Dirac-sea contributions of the quarks. Compared with the case where the Dirac sea is neglected, we find that the inhomogeneous phase shrinks, but in general does not disappear. It is shown within a Ginzburg-Landau analysis that the Lifshitz point of the inhomogeneous phase coincides with the tricritical point if the ratio between sigma-meson and constituent quark mass in vacuum is chosen to be $m_{\sigma }/M=2$, corresponding to the fixed mass ratio in the Nambu–Jona-Lasinio model. In the present model, however, this ratio can be varied, offering the possibility to separate the two points. This is confirmed by our numerical calculations, which demonstrate a strong sensitivity of the size of the inhomogeneous phase on $m_{\sigma }$. Finally, we uncover a general instability of the model with respect to large wave numbers of the chiral modulations, which calls for further improvements beyond the present approximation.

We perform a search for new physics using final states consisting of three leptons and a large imbalance in transverse momentum resulting from proton-antiproton collisions at 1.96 TeV center-of-mass energy. We use data corresponding to $5.8{\mathrm{fb}}^{-1}$ of integrated luminosity recorded by the CDF II detector at the Tevatron collider. Our main objective is to investigate possible new low-momentum (down to $5\mathrm{GeV}/c$) multileptonic final states not investigated by LHC experiments. Relative to previous CDF analyses, we expand the geometric and kinematic coverage of electrons and muons and utilize tau leptons that decay hadronically. Inclusion of tau leptons is particularly important for supersymmetry (SUSY) searches. The results are consistent with standard-model predictions within $1.85\sigma$. By optimizing our event selection to increase sensitivity to the minimal supergravity (mSUGRA) SUSY model, we set limits on the associated production of chargino and next-to-lightest neutralino, the SUSY partners of the electroweak gauge bosons. We exclude cross sections up to 0.1 pb and chargino masses up to $168\mathrm{GeV}/c^2$ at 95% C.L., for a suitable set of mSUGRA parameters. We also exclude a region of the two-dimensional space of the masses of the neutralino and the supersymmetric partner of the tau lepton, not previously excluded at the Tevatron.

The Higgs-Dilaton model is able to produce an early inflationary expansion followed by a dark energy dominated era responsible for the late time acceleration of the Universe. At tree level, the model predicts a small tensor-to-scalar ratio ($0.0021\le r\le 0.0034$), a tiny negative running of the spectral tilt ($-0.00057\le d{n}_s/d\ln k\le -0.00034$) and a nontrivial consistency relation between the spectral tilt of scalar perturbations and the dark energy equation of state, which turns out to be close to a cosmological constant ($0\le 1+w_{DE}\le 0.014$). We reconsider the validity of these predictions in the vicinity of the critical value of the Higgs self-coupling giving rise to an inflection point in the inflationary potential. The value of the inflationary observables in this case strongly depends on the parameters of the model. The tensor-to-scalar ratio can be large [$r\sim \mathcal{O}(0.1)$] and notably exceed its tree-level value. If that happens, the running of the scalar tilt becomes positive and rather big [$d{n}_s/d\ln k\sim \mathcal{O}(0.01)$] and the equation-of-state parameter of dark energy can significantly differ from a cosmological constant [$1+w_{DE}\sim \mathcal{O}(0.1)$].

We study ${\mathrm{AdS}}_7/{\mathrm{CFT}}_6$ correspondence between M theory on ${\mathrm{AdS}}_7\times S^4$ and the 6D $\mathcal{N}=(2,0)$ superconformal field theory. In particular, we focus on Wilson surfaces. We use the conjecture that the (2,0) theory compactified on $S^1$ is equivalent to the 5D maximal super-Yang-Mills (MSYM), and Wilson surfaces wrapping this $S^1$ correspond to Wilson loops in 5D MSYM. The Wilson loops in 5D MSYM obtained by the localization technique result in the Chern-Simons matrix model. We calculate the expectation values of Wilson surfaces in large-rank symmetric representations and antisymmetric representations by using this result. On the gravity side, the expectation values for probe M5-branes wrapping submanifolds of the background are computed. Consequently, we find new, nontrivial evidence for the ${\mathrm{AdS}}_7/{\mathrm{CFT}}_6$ correspondence that the results on the gravity side perfectly agree with those on the CFT side.

Entanglement is studied in the framework of Dyson’s S-matrix theory in relativistic quantum field theory, which leads to a natural definition of entangled states of a particle-antiparticle pair and the spin operator from a Noether current. As an explicit example, the decay of a massive pseudo-scalar particle into a pair of electron and positron is analyzed. Two spin operators are extracted from the Noether current. The Wigner spin operator characterizes spin states at the rest frame of each fermion and, although not measurable in the laboratory, gives rise to a straightforward generalization of low-energy analysis of entanglement to the ultrarelativistic domain. In contrast, if one adopts a (modified) Dirac spin operator, the entanglement measured by spin correlation becomes maximal near the threshold of the decay, while the entanglement is replaced by the classical correlation for the ultrarelativistic electron-positron pair by analogy to the case of neutrinos, for which a hidden-variables type of description is possible. Chiral symmetry differentiates the spin angular momentum and the magnetic moment. The use of weak interaction that can measure helicity is suggested in the analysis of entanglement at high energies instead of a Stern-Gerlach apparatus, which is useless for the electron. A difference between the electron spin at high energies and the photon linear polarization is also noted. The Standard Model can describe all of the observable properties of leptons.

By starting from the modified Maxwell theory coupled to gravity, the arising of geometric quantum phases in the relativistic and nonrelativistic quantum dynamics of a Dirac neutral particle from the effects of the violation of the Lorentz symmetry in the cosmic string spacetime is investigated. It is shown that the Dirac equation can be written in terms of an effective metric and a relativistic geometric phase stems from the topology of the cosmic string spacetime and the Lorentz symmetry breaking effects. Further, the nonrelativistic limit of the Dirac equation is discussed, and it is shown that both Lorentz symmetry breaking effects and the topology of the defect yields a phase shift in the wave function of the nonrelativistic spin-$1/2$ particle.

We discuss the dynamics of intersecting $p$-branes with cosmological constants in the higher-dimensional gravity theories. For the delocalized brane case, these solutions describe an asymptotically de Sitter or power-law expanding universe, while for the partially localized intersecting branes, they describe homogeneous and isotropic universes at each position of the overall transverse space. We then apply these time-dependent branes to the study on the collision of two 0-branes and show that the $0-8$-brane system or the smeared $0-p_I$-brane system can provide an example of colliding branes if they have the same brane charges and only one overall transverse space. Finally, we argue some applications of the solutions in supergravity models.

We study the Misner-Sharp mass for the $f(R)$ gravity in an $n$-dimensional $(\mathrm{n}\ge 3)$ spacetime which permits three-type $(n-2)$-dimensional maximally symmetric subspace. We obtain the Misner-Sharp mass via two approaches. One is the inverse unified first law method and the other is the conserved charge method, which uses a generalized Kodama vector. In the first approach, we assume the unified first law still holds in $n$-dimensional $f(R)$ gravity, which requires a quasilocal mass form (we define it as the generalized Misner-Sharp mass). In the second approach, the conserved charge corresponding to the generalized local Kodama vector is the generalized Misner-Sharp mass. The two approaches, which are bridged by a constraint, are equivalent. This constraint determines the existence of a well-defined Misner-Sharp mass. In an important special case, we present the explicit form for the static space, and we calculate the Misner-Sharp mass for the Clifton-Barrow solution as an example.

Assuming the existence of the dS/CFT correspondence, we construct local scalar fields with $m^2>{(\frac{d}{2})}^2$ in de Sitter space by smearing over conformal field theory operators on the future or past boundary. To maintain bulk microcausality and recover the bulk Wightman function in the Euclidean vacuum, the smearing prescription must involve two sets of single-trace operators with dimensions $\mathrm{\Delta }$ and $d-\mathrm{\Delta }$. Thus the local operator prescription in de Sitter space differs from the analytic continuation from the prescription in anti–de Sitter space. Pushing a local operator in the global patch to future or past infinity is shown to lead to an operator relation between single-trace operators in conformal field theories at ${\mathcal{I}}^{\pm }$, which can be interpreted as a basis transformation, also identified as the relation between an operator in CFT and its shadow operator. Construction of spin$\text{−}s$ gauge field operators is discussed, and it is shown that the construction of higher spin gauge fields in de Sitter space is equivalent to constructing scalar fields with specific values of mass parameter $m^2<{(\frac{d}{2})}^2$. An acausal higher spin bulk operator that matches onto boundary higher spin current is constructed. Implementation of the scalar operator constructions in AdS and dS with embedding formalism is briefly described.