In this paper, we quantify the challenge of explaining the baryon asymmetry using initial conditions in a universe that undergoes inflation. Contrary to lore, we find that such an explanation is possible if net $B-L$ number is stored in a light bosonic field with hyper-Planckian initial displacement and a delicately chosen field velocity prior to inflation. However, such a construction may require extremely tuned coupling constants to ensure that this asymmetry is viably communicated to the Standard Model after reheating; the large field displacement required to overcome inflationary dilution must not induce masses for Standard Model particles or generate dangerous washout processes. While these features are inelegant, this counterexample nonetheless shows that there is no theorem against such an explanation. We also comment on potential observables in the double $\beta$-decay spectrum and on model variations that may allow for more natural realizations.

In this paper we investigate the next-to-minimal composite Higgs model with a $\mathrm{SO}(6)/\mathrm{SO}(5)$ coset, whose pseudo-Nambu-Goldstone boson sector includes a Standard Model singlet in addition to the usual Higgs doublet. The fermions are embedded in the representation $\mathbf{6}$ of SO(6). We study the region of parameter space of the model where the radiatively generated potential has global minima with both the doublet and the singlet fields developing vacuum expectation values. We investigate the consequences of kinetic and mass mixing between the Higgs and the singlet scalar that arise in this framework. We demonstrate that the ensuing doublet-singlet mixing can provide a handle to accommodate heavier resonances (top partners) for a given compositeness scale as compared to the minimal composite Higgs model, thus relaxing the tension with the direct LHC bounds. The main phenomenological consequence of this is a sizable deviation of the Higgs couplings from the Standard Model predictions. While the present experimental precision in the measurement of the Higgs couplings still allows for considerable release of this tension, future measurements of the Higgs branching ratios with increased precision would lead to stringent constraints on this setup.

The purpose of this paper is to demonstrate that if the transformation of a neutron to a mirror neutron exists with an oscillation time of the order of 10 seconds, it can be detected in a rather simple disappearance and/or regeneration type experiment with an intense beam of cold neutrons. In the presence of a conjectural mirror magnetic field of unknown magnitude and direction, the resonance transformation conditions can be found by scanning the magnitude of the ordinary magnetic field in the range, e.g., $\pm 100\mu \mathrm{T}$. Magnetic field is assumed to be uniform along the path of the neutron beam. If the transformation effect exists within this range, the direction and possible time variation of the mirror magnetic field can be determined with additional dedicated measurements.

Models with a light, additional gauge boson are attractive extensions of the standard model. Often these models are only considered as an effective low-energy theory without any assumption about an UV completion. This not only leaves the hierarchy problem of the SM unsolved, but also introduces a copy of it because of the new fundamental scalars responsible for breaking the new gauge group. A possible solution is to embed these models into a supersymmetric framework. However, this gives rise to an additional source of fine-tuning compared to the MSSM and poses a question about how natural such a setup is. One might expect that the additional fine-tuning is huge, namely, $O(M_{\mathrm{SUSY}}^2/m_{Z^{\prime }}^2)$. In this paper, we point out that this is not necessarily the case. We show that it is possible to find a focus point behavior also in the new sector in coexistence with the MSSM focus point. We call this the “double focus point supersymmetry.” Moreover, we stress the need for a proper inclusion of radiative corrections in the fine-tuning calculation: a tree-level estimate would lead to predictions for the tuning which can be wrong by many orders of magnitude. As a showcase, we use the $U(1{)}_{B-L}$ extended MSSM and discuss possible consequences of the observed ${}^8\mathrm{Be}$ anomaly. However, similar features are expected for other models with an extended gauge group which involve potentially large Yukawa-like interactions of the new scalars.

The simplest extension of the standard model is to add a gauge singlet scalar, $S$: the singlet-extended standard model. In the absence of a $Z_2$ symmetry $S\to -S$ and if the new scalar is sufficiently heavy, this model can lead to resonant double Higgs production, significantly increasing the production rate over the standard model prediction. While searches for this signal are being performed, it is important to have benchmark points and models with which to compare the experimental results. In this paper we determine these benchmarks by maximizing the double Higgs production rate at the LHC in the singlet-extended standard model. We find that, within current constraints, the branching ratio of the new scalar into two standard model–like Higgs bosons can be upwards of 0.76, and the double Higgs rate can be increased upwards of 30 times the standard model prediction.

The minimal supersymmetric setup offers a comprehensive framework to interpret the Fermi-LAT Galactic Center excess. Taking into account experimental, theoretical, and astrophysical uncertainties we can identify valid parameter regions linked to different annihilation channels. They extend to dark matter masses above 250 GeV. There exists a very mild tension between the observed relic density and the annihilation rate in the center of our Galaxy for specific channels. The strongest additional constraints come from the new generation of direct detection experiments, ruling out much of the light and intermediate dark matter mass regime and giving preference to heavier dark matter annihilating into a pair of top quarks.

We calculate the parameters describing elastic $I=1$, $P$-wave $\pi \pi$ scattering using lattice QCD with $2+1$ flavors of clover fermions. Our calculation is performed with a pion mass of $m_{\pi }\approx 320\mathrm{MeV}$ and a lattice size of $L\approx 3.6\mathrm{fm}$. We construct the two-point correlation matrices with both quark-antiquark and two-hadron interpolating fields using a combination of smeared forward, sequential and stochastic propagators. The spectra in all relevant irreducible representations for total momenta $|\overrightarrow{P}|\le \sqrt{3}\frac{2\pi }{L}$ are extracted with two alternative methods: a variational analysis as well as multiexponential matrix fits. We perform an analysis using Lüscher’s formalism for the energies below the inelastic thresholds, and investigate several phase shift models, including possible nonresonant contributions. We find that our data are well described by the minimal Breit-Wigner form, with no statistically significant nonresonant component. In determining the $\rho$ resonance mass and coupling we compare two different approaches: fitting the individually extracted phase shifts versus fitting the $t$-matrix model directly to the energy spectrum. We find that both methods give consistent results, and at a pion mass of $a{m}_{\pi }=0.18295(36{)}_{\text{stat}}$ obtain $g_{\rho \pi \pi }=5.69(13{)}_{\text{stat}}(16{)}_{\text{sys}}$, $a{m}_{\rho }=0.4609(16{)}_{\text{stat}}(14{)}_{\text{sys}}$, and $a{m}_{\rho }/a{m}_N=0.7476(38{)}_{\text{stat}}(23{)}_{\text{sys}}$, where the first uncertainty is statistical and the second is the systematic uncertainty due to the choice of fit ranges.

The real-time dissociation of the heavy quarkonium in a strongly coupled boost-invariant non-Abelian plasma relaxing towards equilibrium is analyzed in a holographic framework. The effects driving the plasma out of equilibrium are described by boundary quenching, impulsive variations of the boundary metric. Quarkonium is represented by a classical string with endpoints kept close to the boundary. The evolution of the string profile is computed in the time-dependent geometry, and the dissociation time is evaluated for different configurations with respect to the direction of the plasma expansion. Dissociation occurs quickly for the quarkonium placed in the transverse plane.

We measure the branching fraction and $CP$ violation asymmetry in the decay $B^0\to {\pi }^0{\pi }^0$, using a data sample of $752\times {10}^{6}B\overline{B}$ pairs collected at the $\mathrm{\Upsilon }(4S)$ resonance with the Belle detector at the KEKB $e^{+}{e}^{-}$ collider. The obtained branching fraction and direct $CP$ asymmetry are $\mathcal{B}(B\to {\pi }^0{\pi }^0)=[1.31\pm 0.19(\mathrm{stat})\pm 0.19(\mathrm{syst})]\times {10}^{-6}$ and $A_{CP}=+0.14\pm 0.36(\mathrm{stat})\pm 0.10(\mathrm{syst})$, respectively. The signal significance, including the systematic uncertainty, is 6.4 standard deviations. We combine these results with Belle’s earlier measurements of $B^0\to {\pi }^{+}{\pi }^{-}$ and $B^{\pm }\to {\pi }^{\pm }{\pi }^0$ to exclude the $CP$-violating parameter ${\varphi }_2$ from the range $15.5°<{\varphi }_2<75.0°$ at 95% confidence level.

The photoproduction of isolated photons has been measured in diffractive events recorded by the ZEUS detector at HERA. Cross sections are evaluated in the photon transverse-energy and pseudorapidity ranges $5<E_T^{\gamma }<15\mathrm{GeV}$ and $-0.7<{\eta }^{\gamma }<0.9$, inclusively, and also with a jet with transverse energy and pseudorapidity in the ranges $4<E_T^{\text{jet}}<35\mathrm{GeV}$ and $-1.5<{\eta }^{\text{jet}}<1.8$, using a total integrated electron-proton luminosity of $456{\mathrm{pb}}^{-1}$. A number of kinematic variables were studied and compared to predictions from the rapgap Monte Carlo model. An excess of data is observed above the rapgap predictions for $z_{\mathbb{P}}^{\mathrm{meas}}>0.9$, where $z_{\mathbb{P}}^{\mathrm{meas}}$ is the fraction of the longitudinal momentum of the colorless “Pomeron” exchange that is transferred to the photon-jet final state, giving evidence for direct Pomeron interactions.

The inclusive cross sections for dihadrons of charged pions and kaons ($e^{+}{e}^{-}\to hhX$) in electron-positron annihilation are reported. They are obtained as a function of the total fractional energy and invariant mass for any di-hadron combination in the same hemisphere as defined by the thrust event-shape variable and its axis. Since same-hemisphere dihadrons can be assumed to originate predominantly from the same initial parton, di-hadron fragmentation functions are probed. These di-hadron fragmentation functions are needed as an unpolarized baseline in order to quantitatively understand related spin-dependent measurements in other processes and to apply them to the extraction of quark transversity distribution functions in the nucleon. The di-hadron cross sections are obtained from a $655{\mathrm{fb}}^{-1}$ data sample collected at or near the $\mathrm{\Upsilon }(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider.

We study the process $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}\psi (3686)$ using $5.1{\mathrm{fb}}^{-1}$ of data collected at 16 center-of-mass energy ($\sqrt{s}$) points from 4.008 to 4.600 GeV by the BESIII detector operating at the BEPCII collider. The measured Born cross sections for $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}\psi (3686)$ are consistent with previous results, but with much improved precision. A fit to the cross section shows contributions from two structures: the first has $M=4209.5\pm 7.4\pm 1.4\mathrm{MeV}/c^2$ and $\mathrm{\Gamma }=80.1\pm 24.6\pm 2.9\mathrm{MeV}$, and the second has $M=4383.8\pm 4.2\pm 0.8\mathrm{MeV}/{\mathrm{c}}^2$ and $\mathrm{\Gamma }=84.2\pm 12.5\pm 2.1\mathrm{MeV}$, where the first errors are statistical and the second systematic. The lower-mass resonance is observed in the process $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}\psi (3686)$ for the first time with a statistical significance of $5.8\sigma$. A charged charmoniumlike structure is observed in the ${\pi }^{\pm }\psi (3686)$ invariant mass spectrum for data at $\sqrt{s}=4.416\mathrm{GeV}$. A fit with an $S$-wave Breit-Wigner function yields a mass $M=4032.1\pm 2.4\mathrm{MeV}/c^2$, where the errors are statistical only. However, there are still unresolved discrepancies between the fit model and data. The width of the intermediate state varies in a wide range for different kinematic regions within the data set. Therefore, no simple interpretation of the data has been found, and a future data sample with larger statistics and more theoretical input will be required to better understand this issue.

We report a study of the charmless hadronic decay of the charged $B$ meson to the three-body final state $K^{+}{K}^{-}{\pi }^{+}$. The results are based on a data sample that contains $772\times 10^{6}B\overline{B}$ pairs collected at the $\mathrm{\Upsilon }(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider. The measured inclusive branching fraction and direct $CP$ asymmetry are $(5.38\pm 0.40\pm 0.35)\times {10}^{-6}$ and $-0.170\pm 0.073\pm 0.017$, respectively, where the first uncertainties are statistical and the second are systematic. The $K^{+}{K}^{-}$ invariant mass distribution of the signal candidates shows an excess in the region below $1.5\mathrm{GeV}/c^2$, which is consistent with the previous studies from BABAR and LHCb. In addition, strong evidence of a large direct $CP$ asymmetry is found in the low $K^{+}{K}^{-}$ invariant-mass region.

In this paper we continue analyzing the nonequilibrium dynamics in the $(T^2{)}^n/{\mathbb{Z}}_n$ orbifold conformal field theory. We compute the out-of-time-ordered four-point correlators with twist operators. For rational $\eta (=p/p^{\prime })$ which is the square of the compactification radius, we find that the correlators approach nontrivial constants at late time. For $n=2$ they are expressed in terms of the modular matrices and for higher $n$ orbifolds are functions of $p{p}^{\prime }$ and $n$. For irrational $\eta$, we find a new polynomial decay of the correlators that is a signature of an intermediate regime between rational and chaotic models.

We give a recipe for computing correlation functions of the displacement operator localized on a spherical or planar higher dimensional twist defect using $\mathrm{AdS}/\mathrm{CFT}$. Such twist operators are typically used to construct the $n$th Renyi entropies of spatial entanglement in conformal field theories and are holographically dual to black holes with hyperbolic horizons. The displacement operator then tells us how the Renyi entropies change under small shape deformations of the entangling surface. We explicitly construct the bulk to boundary propagator for the displacement operator insertion as a linearized metric fluctuation of the hyperbolic black hole and use this to extract the coefficient of the displacement operator two point function $C_D$ in any dimension. The $n\to 1$ limit of the twist displacement operator gives the same bulk response as the insertion of a null energy operator in vacuum, which is consistent with recent results on the shape dependence of entanglement entropy and modular energy.

We consider the noncommutative deformation of the finite-temperature holographic QCD (Sakai-Sugimoto) model in external electric and magnetic field and evaluate the effect of the noncommutativity on the properties of the conductor-insulator phase transition associated with a baryon number current. Although the noncommutative deformation of the gauge theory does not change the phase structure with respect to the baryon number current, the transition temperature $T_c$, the transition electric field $e_c$, and magnetic field $b_c$ in the conductor-insulator phase transition depend on the noncommutativity parameter $\theta$. Namely, the noncommutativity of space coordinates have an influence on the shape of the phase diagram for the conductor-insulator phase transition. On the other hand, the allowed range of the noncommutativity parameter can be restricted by the reality condition of the constants of motion.

We investigate the entanglement entropy in $1+1$-dimensional $SU(N)$ gauge theories with various matter fields using the lattice regularization. Here we use extended Hilbert space definition for entanglement entropy, which contains three contributions; (1) classical Shannon entropy associated with superselection sector distribution, where sectors are labeled by irreducible representations of boundary penetrating fluxes, (2) logarithm of the dimensions of their representations, which is associated with “color entanglement,” and (3) EPR Bell pairs, which give “genuine” entanglement. We explicitly show that entanglement entropies (1) and (2) above indeed appear for various multiple “meson” states in gauge theories with matter fields. Furthermore, we employ transfer matrix formalism for gauge theory with fundamental matter field and analyze its ground state using hopping parameter expansion (HPE), where the hopping parameter $K$ is roughly the inverse square of the mass for the matter. We evaluate the entanglement entropy for the ground state and show that all (1), (2), (3) above appear in the HPE, though the Bell pair part (3) appears in higher order than (1) and (2) do. With these results, we discuss how the ground state entanglement entropy in the continuum limit can be understood from the lattice ground state obtained in the HPE.

In this paper, we consider a Lorentz-breaking extension of the theory for a real massive scalar quantum field in the region between two large parallel plates, with our manner to break the Lorentz symmetry being $CPT$ even and aetherlike. For this system, we calculated the Casimir energy considering different boundary conditions. It turns out that the Casimir energy strongly depends on the direction of the constant vector implementing the Lorentz symmetry breaking as well as on the boundary conditions.

We study, in the Schwarzschild spacetime, the resonance interatomic energy (RIE) of two static identical atoms with an interatomic separation $L$ along the radial direction and correlated by a symmetric/antisymmetric entangled state. The atoms are assumed to be coupled to massless scalar fields in the Boulware, Unruh, and Hartle-Hawking vacua, and approximate analytical results are obtained both at infinity and near the horizon. Our results show that at infinity, the RIE approaches that in a flat spacetime, while, near the horizon, they can deviate dramatically from each other. Besides, different from other atomic radiative properties such as the Lamb shift of a single atom or the interatomic energy between two uncorrelated atoms, which can be obviously affected by the thermal character of quantum fields, the RIE of two atoms in a symmetric/antisymmetric entangled state in the Boulware, Unruh, and Hartle-Hawking vacua are exactly the same as a result of the fact that the RIE of two such atoms depends only on the atomic self-reaction, i.e., it does not feel the vacuum fluctuations. This suggests that the RIE of two static atoms in a symmetric/antisymmetric entangled state outside a black hole is oblivious to the Hawking radiation, in contrast to those uncorrelated atoms.