A vector model with a hybrid form of spacetime symmetry breaking consisting of explicit diffeomorphism breaking but spontaneous local Lorentz violation is presented. The combined effects of these symmetry breakings give rise to a theory obeying the Einstein-Maxwell equations in a preferred spatially homogeneous and isotropic frame, with photons emerging as massless Nambu-Goldstone modes. Interpretations and possible generalizations of this model are discussed, and comparisons are made to previous models describing photons as Nambu-Goldstone modes.

We present electric-magnetic (Hodge) duality formulation for non-Abelian gauge groups with $N=1$ supersymmetry in $3+1$ (4D) dimensions. Our system consists of three multiplets: (i) A super-Yang-Mills vector multiplet (YMVM) $({A_{\mu }}^I,{\lambda }^I)$, (ii) a dual vector multiplet (DVM) $({B_{\mu }}^I,{\chi }^I)$, and (iii) an unphysical tensor multiplet (TM) $({C_{\mu \nu }}^I,{\rho }^I,{\phi }^I)$, with the index ${}^I$ for adjoint representation. The multiplets YMVM and DVM are dual to each other like: ${G_{\mu \nu }}^I=(1/2){{\epsilon }_{\mu \nu }}^{\rho \sigma }{F_{\rho \sigma }}^I$. The TM is unphysical, but still plays an important role for establishing the total consistency of the system, based on recently developed tensor-hierarchy formulation. We also apply this technique to non-Abelian electric-magnetic duality in $9+1$ (10D) dimensions. The extra bosonic auxiliary field $K_{{\mu }_1\cdots {\mu }_6}$ in 10D is shown to play an important role for the closure of supersymmetry on fields.

Super Feynman rules for any superspin are given for massive $\mathcal{N}=1$ supersymmetric theories, including momentum superspace on-shell legs. This is done by extending, from space to superspace, Weinberg’s perturbative approach to quantum field theory. Superfields work just as a device that allow one to write super Poincaré-covariant superamplitudes for interacting theories, relying neither in path integral nor canonical formulations. Explicit transformation laws for particle states under finite supersymmetric transformations are offered. $C$, $P$, $T$, and $\mathcal{R}$ transformations are also worked out. A key feature of this formalism is that it does not require the introduction of auxiliary fields, and when introduced, their purpose is just to render supersymmetric invariant the time-ordered products in the Dyson series. The formalism is tested for the cubic scalar superpotential. It is found that when a superparticle is its own antisuperparticle the lowest-order correction of time-ordered products, together with its covariant part, corresponds to the Wess–Zumino model potential.

We study the nonperturbative dynamics of the standard model (SM) after inflation, in the regime where the SM is decoupled from (or weakly coupled to) the inflationary sector. We use classical lattice simulations in an expanding box in ($3+1$) dimensions, modeling the SM gauge interactions with both global and Abelian-Higgs analogue scenarios. We consider different postinflationary expansion rates. During inflation, the Higgs forms a condensate, which starts oscillating soon after inflation ends. Via nonperturbative effects, the oscillations lead to a fast decay of the Higgs into the SM species, transferring most of the energy into $Z$ and $W^{\pm }$ bosons. All species are initially excited far away from equilibrium, but their interactions lead them into a stationary stage, with exact equipartition among the different energy components. From there on, the system eventually reaches equilibrium. We have characterized in detail, in the different expansion histories considered, the evolution of the Higgs and of its dominant decay products until equipartition is established. We provide a useful mapping between simulations with different parameters, from which we derive a master formula for the Higgs decay time as a function of the coupling constants, Higgs initial amplitude and postinflationary expansion rate.

We present a direct confirmation of the validity of the equivalence principle for unstructured test bodies in scalar-tensor gravity. Our analysis is complementary to previous approaches and valid for a large class of scalar-tensor theories of gravitation. A covariant approach is used to derive the equations of motion in a systematic way and allows for the experimental test of scalar-tensor theories by means of extended test bodies.

We propose a model to study the importance of double parton scattering (DPS) in Mueller-Navelet jets production at the LHC which is consistent with the Balitsky-Fadin-Kuraev-Lipatov framework used to compute the single parton scattering contribution to this process. We study this model in kinematics corresponding to existing and possible future measurements at the LHC and estimate the importance of this DPS contribution on relevant observables for this process, namely the cross section and the azimuthal correlation of the jets.

In this paper, we study double charmonia production in upsilon peaks, especially a S-wave charmonium ${\eta }_c$ and a P-wave charmonium $h_c({}^1{P}_1)$, or a S-wave charmonium $J/\psi$ and the $X(3940)$ and $X(4160)$ within the nonrelativistic QCD (NRQCD) approach, which is a powerful tool to realize the factorization of double charmonia production in electron-positron annihilation. The $J^{\mathrm{PC}}=1^{--}$ state $\mathrm{\Upsilon }(nS)$ can provide an ideal laboratory for studying the properties of double-heavy quarkonium and also can separate the perturbative and nonperturbative parts due to the large heavy quark mass compared with the typical hadron scale ${\mathrm{\Lambda }}_{\mathrm{QCD}}$. Explanation of the $X(3940)$ and $X(4160)$ as the $3{{}^{1}S}_0$ and $4{{}^{1}S}_0$ states, respectively, are compatible with the observed upper limits for the branching fractions of $\mathrm{\Upsilon }(1S,2S)\to J/\psi +X$, where $X=X(3940)$, $X(4160)$ by the Belle Collaboration. The branching fractions of $\mathrm{\Upsilon }(1S,2S,3S)\to {\eta }_c+h_c({}^1{P}_1)$ are predicted to be around $10^{-6}$, which shall be tested in Belle-II experiments.

In this short note, we argue that the Burkardt sum rule for the Sivers functions can be used to check the consistency of evolution equations of three-parton correlators.

In this paper, we study the anomalous flavor changing neutral current Yukawa interactions between the top quark, the Higgs boson, and either an up or charm quark ($tqH,q=u,c$). We probe these couplings in $e^{-}p\to {\nu }_e\overline{t}\to {\nu }_{e}H\overline{q}$ and the channel $e^{-}p\to {\nu }_{e}Hb$. Both channels are induced by charged current interactions through $e^{-}p$ collision at the Large Hadron Electron Collider (LHeC). We study the signatures with the Higgs decay modes $H\to \gamma \gamma ,b\overline{b}$ and ${\tau }^{+}{\tau }^{-}$. Our results show that the flavor changing couplings ${\kappa }_{tqH}$ can be probed down to a value of 0.0162 in $e^{-}p\to {\nu }_e\overline{t}\to {\nu }_{e}H\overline{q}$ with $H\to b\overline{b}$ at a 14 TeV LHeC with a 150 GeV electron beam and $200{\mathrm{fb}}^{-1}$ luminosity. This value of the coupling corresponds to the branching ratio $\mathrm{Br}(t\to qH)=1.34\times {10}^{-4}$.

We study a simplified model of the Standard Model (SM) Higgs boson decaying to a degenerate pair of scalars which travel a macroscopic distance before decaying to SM particles. This is the leading signal for many well-motivated solutions to the hierarchy problem that do not propose additional light colored particles. Bounds for displaced Higgs boson decays below 10 cm are found by recasting existing tracker searches from Run I. New tracker search strategies, sensitive to the characteristics of these models and similar decays, are proposed with sensitivities projected for Run II at $\sqrt{s}=13\mathrm{TeV}$. With $20{\mathrm{fb}}^{-1}$ of data, we find that Higgs branching ratios down to $2\times 10^{-4}$ can be probed for centimeter decay lengths.

CDMS II data from the five-tower runs at the Soudan Underground Laboratory were reprocessed with an improved charge-pulse fitting algorithm. Two new analysis techniques to reject surface-event backgrounds were applied to the 612 kg days germanium-detector weakly interacting massive particle (WIMP)-search exposure. An extended analysis was also completed by decreasing the 10 keV analysis threshold to $\sim 5\mathrm{keV}$, to increase sensitivity near a WIMP mass of $8\mathrm{GeV}/c^2$. After unblinding, there were zero candidate events above a deposited energy of 10 keV and six events in the lower-threshold analysis. This yielded minimum WIMP-nucleon spin-independent scattering cross-section limits of $1.8\times {10}^{-44}$ and $1.18\times {10}^{-41}$ at 90% confidence for 60 and $8.6\mathrm{GeV}/c^2$ WIMPs, respectively. This improves the previous CDMS II result by a factor of 2.4 (2.7) for 60 $(8.6)\mathrm{GeV}/c^2$ WIMPs.

We investigate a fourth order model of gravity, having a free length parameter, and no cosmological constant or dark energy. We consider cosmological evolution of a flat Friedmann universe in this model for the case that the length parameter is of the order of the present Hubble radius. By making a suitable choice for the present value of the Hubble parameter, and the value of the third derivative of the scale factor (the jerk), we find that the model can explain cosmic acceleration to the same degree of accuracy as the standard concordance model. If the free length parameter is assumed to be time dependent, and of the order of the Hubble parameter of the corresponding epoch, the model can still explain cosmic acceleration, and provides a possible resolution of the cosmic coincidence problem. We work out the effective equation of state, and its time evolution, in our model. The fourth order correction terms are proportional to the metric, and hence mimic the cosmological constant. We also compare redshift drift in our model, with that in the standard model. The equation of state and the redshift drift serve to discriminate our model from the standard model.

We present analytic computations of gauge invariant quantities for a point mass in a circular orbit around a Schwarzschild black hole, giving results up to 15.5 post-Newtonian order in this paper and up to 21.5 post-Newtonian order in an online repository. Our calculation is based on the functional series method of Mano, Suzuki, and Takasugi (MST) and a recent series of results by Bini and Damour. We develop an optimized method for generating post-Newtonian expansions of the MST series, enabling significantly faster computations. We also clarify the structure of the expansions for large values of $\ell$, and in doing so develop an efficient new method for generating the MST renormalized angular momentum, $\nu$.

Nonlinear theories generalizing Maxwell’s electromagnetism and arising from a Lagrangian formalism have dispersion relations in which propagation planes factor into null planes corresponding to two effective metrics which depend on the pointwise values of the electromagnetic field. These effective Lorentzian metrics share the null (generically two) directions of the electromagnetic field. We show that the theory is symmetric hyperbolic if and only if the cones these metrics give rise to have a nonempty intersection, namely, that there exist families of symmetrizers in the sense of Geroch [26] which are positive definite for all covectors in the interior of the cones intersection. Thus, for these theories, the initial value problem is well posed. We illustrate the power of this approach with several nonlinear models of physical interest such as Born–Infeld, Gauss–Bonnet, and Euler–Heisenberg.

The $B$-mode of polarized anisotropies of the cosmic microwave background is a unique and nearly direct probe of primordial inflation, as it can constrain the amplitude of the primordial gravity waves. However, its detection and precise measurement is made difficult by a minute amplitude of the signal and the fact that the signal has to be discerned from many contributions of noncosmological origin and reliably estimated in the presence of numerous sources of statistical uncertainties. Among these last effects, the $E$-to-$B$ leakage, arising as a result of partial sky coverage, has been found to play a key and potentially fundamental role in determining the possible statistical significance with which the primordial $B$-mode signal can be detected. In this work we employ the pure pseudospectrum formalism devised to minimize the effects of the leakage on the variance of power spectrum estimates and discuss the limits on the tensor-to-scalar ratio, $r$, that could be realistically set by current and forthcoming measurements of the $B$-mode angular power spectrum. We compare those with the results obtained using other approaches: naive mode counting, minimum-variance quadratic estimators, and revisiting the question of optimizing the sky coverage of small-scale, suborbital experiments in order to maximize the statistical significance of the detection of $r$. We show that the optimal sky coverage is largely insensitive to the adopted approach at least for reasonably compact sky patches. We find, however, that the mode counting overestimates the detection significance by a factor $\sim 1.17$ as compared to the lossless maximum variance approach and by a factor $\sim 1.25$ as compared to the lossy pure pseudospectrum estimator. In a second time, we consider more realistic experimental configurations. With a pure pseudospectrum reconstruction of $B$-modes and considering only statistical uncertainties, we find that a detection of $r\sim 0.11$, $r\sim 0.0051$, and $r\sim 0.0026$ at 99% confidence level is within the reach of current suborbital experiments, future arrays of ground-based telescopes, and a satellite mission, respectively. This means that an array of telescopes could be sufficient to discriminate between large- and small-field models of inflation, even if the $E$-to-$B$ leakage is consistently included but accounted for in the analysis. However, a satellite mission will be required to distinguish between different small-field models depending on the number of $e$-folds.

In the inert scalar doublet framework, we analyze what would be the effect of a $B-L$ asymmetry that could have been produced at high temperature in the thermal bath of the Universe. We show that unless the “${\lambda }_5$” scalar interaction is tiny, this asymmetry is automatically reprocessed in part into an inert scalar asymmetry that could be at the origin of dark matter today. Along this scenario, the inert mass scale lies in the few-TeV range, and direct detection constraints require that the inert scalar particles decay into a lighter dark matter particle which, as the inert doublet, is odd under a $Z_2$ symmetry.

We present a search for ten baryon number violating decay modes of $\mathrm{\Lambda }$ hyperons using the CLAS detector at Jefferson Laboratory. Nine of these decay modes result in a single meson and single lepton in the final state ($\mathrm{\Lambda }\to m\ell$) and conserve either the sum or the difference of baryon and lepton number ($B\pm L$). The tenth decay mode ($\mathrm{\Lambda }\to \overline{p}{\pi }^{+}$) represents a difference in baryon number of two units and no difference in lepton number. We observe no significant signal and set upper limits on the branching fractions of these reactions in the range $(4–200)\times {10}^{-7}$ at the 90% confidence level.

We model the soft Pomeron in QCD using a scalar Polyakov string with extrinsic curvature in the bottom-up approach of holographic QCD. The overall dipole-dipole scattering amplitude in the soft Pomeron kinematics is shown to be sensitive to the extrinsic curvature of the string for finite momentum transfer. The characteristics of the diffractive peak in the differential elastic $pp$ scattering are affected by a small extrinsic curvature of the string.

Eugenio Bianchi and Matteo Smerlak have found a relationship between the Hawking radiation energy and von Neumann entropy in a conformal field emitted by a semiclassical two-dimensional black hole. We compare this relationship with what might be expected for unitary evolution of a quantum black hole in four and higher dimensions. If one neglects the expected increase in the radiation entropy over the decrease in the black hole Bekenstein-Hawking $A/4$ entropy that arises from the scattering of the radiation by the barrier near the black hole, the relation works very well, except near the peak of the radiation von Neumann entropy and near the final evaporation. These discrepancies are calculated and discussed as tiny differences between a semiclassical treatment and a quantum gravity treatment.