A search for the doubly charged Higgs $({\delta }^{\pm \pm })$ is performed in the two-Higgs-doublet extension of the conventional type-II seesaw model. We find that a fantastic mixing effect between the singly charged Higgses of the Higgs doublet and triplet arises from the scalar potential. The mixing leads to the following intriguing phenomena: (i) the mass splittings in triplet particles are magnified; (ii) QCD processes dominate the production of ${\delta }^{\pm \pm }$; and (iii) the new predominant decay channels of ${\delta }^{\pm \pm }$ are ${\delta }^{\pm \pm }\to W^{{\pm }^{[*]}}{H}_{1(2)}^{{\pm }^{(*)}}$, but not ${\delta }^{\pm }\to ({\ell }^{\pm }{\ell }^{\pm },W^{\pm }{W}^{\pm })$, which are usually discussed in the literature. With a luminosity of $40{\mathrm{fb}}^{-1}$ and collision energy of 13 TeV, we demonstrate that a ${\delta }^{\pm \pm }$ with mass below 330 GeV could be observed at the $5\sigma$ level. Moreover, when the luminosity approaches $300{\mathrm{fb}}^{-1}$, the observed mass of ${\delta }^{\pm \pm }$ could reach up to 450 GeV.

The dynamics of a particle influenced by strongly coupled quantum critical theories is studied by the holographic approach. Based upon the bottom-up approach a real-time prescription for the AdS/CFT correspondence in the context of nonequilibrium physics is developed in accordance with the field theoretic requirements, by which the associated holographic influence functional is obtained. We then study the decoherence dynamics of a particle induced by the quantum critical theories with a dynamical exponent $z$. We find that as $z$ increases, the decoherence effect becomes less significant. Similar behavior is found as we heat up the environment. However, in this case the decoherence effect is enhanced not only by its strong coupling constant but also from the finite temperature effect. Finally a comparison is made with the result of a particle influenced by the free field.

Using the gauge-gravity duality, we argue that for a certain class of out-of-equilibrium steady-state systems in contact with a thermal background at a given temperature, the macroscopic physics can be captured by an effective thermodynamic description. The steady state is obtained by applying a constant electric field that results in a stationary current flow. Within holography, we consider generic probe systems where an open-string equivalence principle and an open-string metric govern the effective thermodynamics. This description comes equipped with an effective temperature, which is larger than the background temperature, and a corresponding effective entropy. For conformal or scale-invariant theories, certain scaling behaviors follow immediately. In general, in the large electric field limit, this effective temperature is also observed to obey generic relations with various physical parameters in the system.

We compute the renormalized entanglement entropy (REE) for BPS black solutions in $\mathcal{N}=2$, four-dimensional gauged supergravity. We find that this quantity decreases monotonically with the size of the entangling region until it reaches a critical point, then increases and approaches the entropy density of the brane. This behavior can be understood as a consequence of the renormalized entanglement entropy being driven by two competing factors, namely, entanglement and the mixedness of the black brane. In the UV, entanglement dominates, whereas in the IR, the mixedness takes over.

We investigate quarkonium mass spectra in external constant magnetic fields by using QCD sum rules. We first discuss a general framework of QCD sum rules necessary for properly extracting meson spectra from current correlators computed in the presence of strong magnetic fields, that is, a consistent treatment of mixing effects caused in the mesonic degrees of freedom. We then implement operator product expansions for pseudoscalar and vector heavy-quark current correlators by taking into account external constant magnetic fields as operators and obtain mass shifts of the lowest-lying bound states ${\eta }_c$ and $J/\psi$ in the static limit with their vanishing spatial momenta. Comparing results from QCD sum rules with those from hadronic effective theories, we find that the dominant origin of mass shifts comes from a mixing between ${\eta }_c$ and $J/\psi$ with a longitudinal spin polarization, accompanied by other subdominant effects such as mixing with higher excited states and continua.

We calculate the low-energy effective action of massless and massive complex linear superfields coupled to a massive U(1) vector multiplet. Our calculations include superspace higher-derivative corrections and therefore go beyond previous results. Among the superspace higher derivatives, we find that terms that lead to a deformation of the auxiliary field potential and may break supersymmetry are also generated. We show that the supersymmetry breaking vacua can only be trusted if there exists a hierarchy between the higher-order terms. A renormalization group analysis shows that generically a hierarchy is not generated by the quantum corrections.

The equivalence between thermal field theory and the Boltzmann transport equation is investigated at higher orders in the context of quantum electrodynamics. We compare the contributions obtained from the collisionless transport equation with the high temperature limit of the one-loop thermal Green’s function. Our approach employs the representation of the thermal Green’s functions in terms of forward scattering amplitudes. The general structure of these amplitudes clearly indicates that the physics described by the leading high temperature limit of quantum electrodynamics can be obtained from the Boltzman transport equation. We also present some explicit examples of this interesting equivalence.

We discuss the physical implications of formulating the Standard Model (SM) in terms of the superconnection formalism involving the superalgebra $su(2/1)$. In particular, we discuss the prediction of the Higgs mass according to the formalism and point out that it is $\sim 170\mathrm{GeV}$, in clear disagreement with experiment. To remedy this problem, we extend the formalism to the superalgebra $su(2/2)$, which extends the SM to the left-right symmetric model (LRSM) and accommodates a $\sim 126\mathrm{GeV}$ Higgs boson. Both the SM in the $su(2/1)$ case and the LRSM in the $su(2/2)$ case are argued to emerge at $\sim 4\mathrm{TeV}$ from an underlying theory in which the spacetime geometry is modified by the addition of a discrete extra dimension. The formulation of the exterior derivative in this model space suggests a deep connection between the modified geometry, which can be described in the language of noncommutative geometry, and the spontaneous breaking of the gauge symmetries. The implication is that spontaneous symmetry breaking could actually be geometric/quantum gravitational in nature. The nondecoupling phenomenon seen in the Higgs sector can then be reinterpreted in a new light as due to the mixing of low energy (SM) physics and high energy physics associated with quantum gravity, such as string theory. The phenomenology of a TeV scale LRSM is also discussed, and we argue that some exciting discoveries may await us at the LHC, and other near-future experiments.

In this paper, we extend the study on the nonlinear power-law Maxwell field to dilaton gravity. We introduce the $(n+1)$-dimensional action in which gravity is coupled to a dilaton and power-law nonlinear Maxwell field, and we obtain the field equations by varying the action. We construct a new class of higher dimensional topological black hole solutions of Einstein-dilaton theory coupled to a power-law nonlinear Maxwell field and investigate the effects of the nonlinearity of the Maxwell source as well as the dilaton field on the properties of the spacetime. Interestingly enough, we find that the solutions exist provided one assumes three Liouville-type potentials for the dilaton field, and in the case of the Maxwell field, one of the Liouville potentials vanishes. After studying the physical properties of the solutions, we compute the mass, charge, electric potential and temperature of the topological dilaton black holes. We also study the thermodynamics and thermal stability of the solutions and disclose the effects of the dilaton field and the power-law Maxwell field on the thermodynamics of these black holes. Finally, we comment on the dynamical stability of the obtained solutions in four dimensions.

We study the $f$-mode frequencies and damping times of nonrotating neutron stars (NS) in general relativity by solving the linearized perturbation equations, with the aim to establish “universal” relations that depend only weakly on the equations of state (EOS). Using a more comprehensive set of EOSs, we reexamine some proposed empirical relations that describe the $f$-mode parameters in terms of mass and radius of the NS, and we test a more recent proposal for expressing the $f$-mode parameters as quadratic functions of the effective compactness. Our extensive results for each equation of state considered allow us to study the accuracy of each proposal. In particular, the empirical relation proposed in the literature for the damping time in terms of the mass and radius deviates considerably from our results. We introduce a new universal relation for the product of the $f$-mode frequency and damping time as a function of the (ordinary) compactness, which proved to be more accurate. The more recently proposed relations using the effective compactness, on the other hand, also fit our data accurately. Our results show that the maximum oscillation frequency depends strongly on the EOS, such that the measurement of a high oscillation frequency would rule out several EOSs. Lastly, we compare the exact mode frequencies to those obtained in the Cowling approximation, and also to results obtained with a nonlinear evolution code, validating the implementations of the different approaches.

In this paper we start a systematic investigation of applying an adaptive finite element method to the Einstein equations, especially binary compact object simulations. To our knowledge, this is the first study on this topic. Puncture type initial data are solved with the adaptive finite element method. The numerical scheme proposed in the current work can be straightforwardly extended to the general type of initial data of the Einstein equations. The Parallel Hierarchical Grid library and the existing numerical relativity code AMSS-NCKU are used to develop the adaptive finite element Einstein solver. In the unsmooth toy model problem, the adaptive mesh refinement operation can catch the unsmooth region efficiently. The numerical solution deviates the exact solution by an error less than $10^{-5}$. In the binary black hole problem, our solution is consistent with the one gotten by the TwoPuncture code which uses a pseudospectral method. As we expected, the solution gotten by the finite element method is less accurate than that gotten by the spectral method. But the relative error distributes almost uniformly. The adaptive mesh refinement method is quite efficient and it does not waste computational effort. Our finite element code is more flexible than the TwoPuncture code. It can be used to treat other general initial data problems such as the three black holes problem, besides the binary black hole problem. We test one typical three black holes problem also. In all of the test cases, our adaptive finite element code works quite well.

Measuring the volume weighted velocity power spectrum suffers from a severe systematic error due to imperfect sampling of the velocity field from the inhomogeneous distribution of dark matter particles/halos in simulations or galaxies with velocity measurement. This “sampling artifact” depends on both the mean particle number density ${\overline{n}}_P$ and the intrinsic large scale structure (LSS) fluctuation in the particle distribution. (1) We report robust detection of this sampling artifact in $N$-body simulations. It causes $\sim 12\%$ underestimation of the velocity power spectrum at $k=0.1h/\mathrm{Mpc}$ for samples with ${\overline{n}}_P=6\times {10}^{-3}(\mathrm{Mpc}/h{)}^{-3}$. This systematic underestimation increases with decreasing ${\overline{n}}_P$ and increasing $k$. Its dependence on the intrinsic LSS fluctuations is also robustly detected. (2) All of these findings are expected based upon our theoretical modeling in paper I [P. Zhang, Y. Zheng, and Y. Jing, Sampling artifact in volume weighted velocity measurement. I. Theoretical modeling, arXiv:1405.7125.]. In particular, the leading order theoretical approximation agrees quantitatively well with the simulation result for ${\overline{n}}_P\gtrsim 6\times {10}^{-4}(\mathrm{Mpc}/h{)}^{-3}$. Furthermore, we provide an ansatz to take high order terms into account. It improves the model accuracy to $\lesssim 1\%$ at $k\lesssim 0.1h/\mathrm{Mpc}$ over 3 orders of magnitude in ${\overline{n}}_P$ and over typical LSS clustering from $z=0$ to $z=2$. (3) The sampling artifact is determined by the deflection $\mathbf{D}$ field, which is straightforwardly available in both simulations and data of galaxy velocity. Hence the sampling artifact in the velocity power spectrum measurement can be self-calibrated within our framework. By applying such self-calibration in simulations, it is promising to determine the real large scale velocity bias of ${10}^{13}{M}_{\odot }$ halos with $\sim 1\%$ accuracy, and that of lower mass halos with better accuracy. (4) In contrast to suppressing the velocity power spectrum at large scale, the sampling artifact causes an overestimation of the velocity dispersion. We prove that a correlation between the signal field ($\mathbf{v}$) and the sampling field ($\mathbf{D}$) is a major cause. This complexity, among other issues, is carefully investigated to further improve understanding of the sampling artifact.

Cosmology based on large scale peculiar velocity prefers volume weighted velocity statistics. However, measuring the volume weighted velocity statistics from inhomogeneously distributed galaxies (simulation particles/halos) suffers from an inevitable and significant sampling artifact. We study this sampling artifact in the velocity power spectrum measured by the nearest particle velocity assignment method by Zheng et al., [Phys. Rev. D 88, 103510 (2013).]. We derive the analytical expression of leading and higher order terms. We find that the sampling artifact suppresses the $z=0$ $E$-mode velocity power spectrum by $\sim 10\%$ at $k=0.1h/\mathrm{Mpc}$, for samples with number density ${10}^{-3}(\mathrm{Mpc}/h{)}^{-3}$. This suppression becomes larger for larger $k$ and for sparser samples. We argue that this source of systematic errors in peculiar velocity cosmology, albeit severe, can be self-calibrated in the framework of our theoretical modelling. We also work out the sampling artifact in the density-velocity cross power spectrum measurement. A more robust evaluation of related statistics through simulations will be presented in a companion paper by Zheng et al., [Sampling artifact in volume weighted velocity measurement. II. Detection in simulations and comparison with theoretical modelling, arXiv:1409.6809.]. We also argue that similar sampling artifact exists in other velocity assignment methods and hence must be carefully corrected to avoid systematic bias in peculiar velocity cosmology.

The excited baryon masses are analyzed in the framework of the $1/N_c$ expansion using the available physical masses and also the masses obtained in lattice QCD for different quark masses. The baryon states are organized into irreducible representations of $\mathrm{SU}(6)\times \mathrm{O}(3)$, where the $[\mathbf{56},{\ell }^P=0^{+}]$ ground-state and excited baryons, and the $[\mathbf{56},2^{+}]$ and $[\mathbf{70},1^{-}]$ excited states are analyzed. The analyses are carried out to $\mathcal{O}(1/N_c)$ and first order in the quark masses. The issue of state identifications is discussed. Numerous parameter-independent mass relations result at those orders, among them the well known Gell-Mann-Okubo and equal-spacing relations, as well as additional relations involving baryons with different spins. It is observed that such relations are satisfied at the expected level of precision. From the quark-mass dependence of the coefficients in the baryon mass formulas an increasingly simpler picture of the spin-flavor composition of the baryons is observed with increasing pion mass (equivalently, increasing $m_{u,d}$ masses), as measured by the number of significant mass operators.

In view of the first measurement of the branching fraction for $J/\psi \to {\pi }^0{e}^{+}{e}^{-}$ by the BESIII collaboration, we analyze what can be learned on the corresponding transition form factor using dispersion theory. We show that light-quark degrees of freedom dominate the spectral function, in particular two-pion intermediate states. Estimating the effects of multipion states as well as charmonium, we arrive at a prediction for the complete form factor that should be scrutinized experimentally in the future.

We study two simple and well-motivated nonuniversal gaugino mass models, which predict Higgsino dark matter. One can account for the observed dark matter relic density along with the observed Higgs boson mass of $\simeq 125\mathrm{GeV}$ over a large region of the parameter space of each model, corresponding to a Higgsino mass of $\simeq 1\mathrm{TeV}$. In each case this parameter region covers the gluino mass range of 2–3 TeV, parts of which can be probed by the 14 TeV LHC experiments. We study these model predictions for the LHC in brief and for dark matter detection experiments in greater detail.

We discuss the impact of the two-loop corrections to the Higgs mass in the next-to-minimal supersymmetric standard model beyond $O({\alpha }_S({\alpha }_b+{\alpha }_t))$. For this purpose we use the combination of the public tools sarah and SPheno to include all contributions stemming from superpotential parameters. We show that the corrections in the case of a heavy singlet are often MSSM-like and reduce the predicted mass of the SM-like state by about 1 GeV as long as $\lambda$ is moderately large. For larger values of $\lambda$ the additional corrections can increase the SM-like Higgs mass. If a light singlet is present the additional corrections become more important even for smaller values of $\lambda$ and can even dominate the ones involving the strong interaction. In this context we point out that important effects are not reproduced quantitatively when only including $O(({\alpha }_b+{\alpha }_t+{\alpha }_{\tau }{)}^2)$ corrections known from the MSSM.

In the $SU(2)$ Yang–Mills theory on the four-dimensional Euclidean lattice, we confirm the gauge-independent “Abelian” dominance (or the restricted field dominance) and gauge-independent magnetic-monopole dominance in the string tension of the linear potential extracted from the Wilson loop in the fundamental representation. The dual Meissner effect is observed by demonstrating the squeezing of the chromoelectric field flux connecting a pair of a quark and an antiquark. In addition, the circular magnetic-monopole current is induced around the chromoelectric flux. The type of the dual superconductivity is also determined by fitting the result with the dual Ginzburg–Landau model. Thus, the dual superconductor picture for quark confinement is supported in a gauge-independent manner. These results are obtained based on a reformulation of the lattice Yang–Mills theory based on the change of variables à la Cho–Duan-Ge–Faddeev–Niemi combined with a non-Abelian Stokes theorem for the Wilson loop operator. We give a new procedure (called the reduction) for obtaining the color direction field that plays the central role in this reformulation.

We investigate the quark Wigner distributions in a light-cone spectator model. The Wigner distribution, as a quasidistribution function, provides the most general one-parton information in a hadron. Combining the polarization configurations, unpolarized, longitudinal polarized, or transversal polarized, of the quark and the proton, we can define 16 independent Wigner distributions at leading twist. We calculate all these Wigner distributions for the $u$ quark and the $d$ quark, respectively. In our calculation, both the scalar and the axial-vector spectators are included, and the Melosh–Wigner rotation effects for both the quark and the axial-vector spectator are taken into account. The results provide us a very rich picture of the quark structure in the proton.

In this paper we utilize our improved quasiparticle model to obtain the equation of state (EOS) and use it as an input to the Tolman-Oppenheimer-Volkoff (TOV) equation to get the mass-radii relation of a pure quark star. We discuss the relation between structures of quark stars and the parameters in the EOS and get a maximum mass of quark star over two solar mass. To compare the result with recent observation, we also calculate the structure of a hybrid star and consider the influence of rotation. Finally, the hadron-quark phase transition in the interior of neutron stars and how much energy will be released when a neutron star bursts into a quark star are discussed.