We consider in the 3-3-1 model with heavy leptons the box contributions to the mass difference in $K$ and $B$ neutral mesons induced by neutral (pseudo)scalars, exotic charged quarks, singly and doubly charged scalar and gauge bosons. In particular, we include the effects of a real scalar with mass near 125 GeV but with nondiagonal couplings to quarks. We show that, as in the tree level case, there are ranges of the parameters in which these contributions can be suppressed enough by negative interference among several amplitudes. Hence, in this model these $\mathrm{\Delta }F=2$ processes may be dominated by the standard model contributions. Our results are valid in the minimal 3-3-1 model without the sextet.

While it is revealed that the cosmic microwave background (CMB) is linearly polarized at 10% level, it is predicted that there exists no significant intrinsic source for circular polarization ($CP$) in the standard cosmology. However, during the propagation through a magnetized plasma, the $CP$ of the CMB could be produced via the Faraday conversion (FC). The FC converts a preexisting linear polarization into $CP$ in the presence of a magnetic field with relativistic electrons. In this paper, we focus on the FC due to supernova remnants of the first stars, also called pop III stars. We derive an analytic form for the angular power spectrum of the $CP$ of the CMB generated by the general FC. We apply this result to the case of the FC triggered by explosions of the first stars and evaluate the angular power spectrum, $C_l^{VV}$. We show that the amplitude of $l(l+1)C_l^{VV}/(2\pi )$ $>10^{-2}\mu {\mathrm{K}}^2$ for $l>100$, with only one pop III star per halo, the age of pop III SN remnants as ${10}^4\text{years}$ and frequency of CMB observation as 1 GHz. We expect the $CP$ of the CMB to be a very promising probe of the yet unobserved first stars, primarily due to the expected high signal along with a unique frequency dependence.

We present a new probe of strongly coupled electroweak symmetry breaking at the 14 TeV LHC by measuring a phase shift in the event distribution of the decay azimuthal angles in massive gauge boson scattering. One generically expects a large phase shift in the longitudinal gauge boson scattering amplitude due to the presence of broad resonances. This phase shift is observable as an interference effect between the strongly interacting longitudinal modes and the transverse modes of the gauge bosons. We find that even very broad resonances of masses up to 900 GeV can be probed at $3\sigma$ significance with a $3000{\mathrm{fb}}^{-1}$ run of the LHC by using this technique. We also present the estimated reach for a future 50 TeV proton-proton collider.

We show that the hadronic “heat capacity” calculated as a function of temperature may be used to infer the possible presence of different scales underlying the dynamical structure of hadronic resonances using the phenomenon of Schottky anomaly. We first demonstrate this possibility with the well-known meson spectrum in various channels and then comment on the possibility of using this method as a diagnostic to distinguish the exotic states.

We propose a universal form for quark and lepton mass matrices, which applies in a “leading order” approximation where $CP$-violating phases are ignored. Down-quark mass ratios are successfully predicted in our scheme using the measured Cabibbo-Kobayashi-Maskawa mixing angles as input. Assuming an additional discrete symmetry in the neutrino sector, we obtain the “golden ratio” pattern in the leading-order Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix; in addition we predict an inverted neutrino mass hierarchy with $m_1\simeq m_2\simeq 74\mathrm{meV}$, $m_3\simeq 55\mathrm{meV}$, and neutrinoless double beta decay mass parameter $m_{0\nu \beta \beta }\simeq 33\mathrm{meV}$. When $CP$-violating phases are included, our scheme suggests a residual ${\mathbb{Z}}_2$ antiunitary symmetry of the neutrino mass matrix, in which the interchange of $\mu$ and $\tau$ neutrinos is accompanied by a time reversal transformation, thus predicting that the $CP$-violating angle in the neutrino sector is close to the maximal value $\delta =\pm \pi /2$, and that the diagonal phases in the PMNS matrix are ${\alpha }_1\simeq 0$, ${\alpha }_2\simeq \pi$.

A search for the rare decay of a $B^0$ or $B_s^0$ meson into the final state $J/\psi \gamma$ is performed, using data collected by the LHCb experiment in $pp$ collisions at $\sqrt{s}=7$ and 8 TeV, corresponding to an integrated luminosity of $3{\mathrm{fb}}^{-1}$. The observed number of signal candidates is consistent with a background-only hypothesis. Branching fraction values larger than $1.5\times 10^{-6}$ for the $B^0\to J/\psi \gamma$ decay mode are excluded at 90% confidence level. For the $B_s^0\to J/\psi \gamma$ decay mode, branching fraction values larger than $7.3\times 10^{-6}$ are excluded at 90% confidence level; this is the first branching fraction limit for this decay.

The flavor-singlet component of the ${\eta }^{\prime }$ meson is related to the topological structure of the SU(3) gauge field through the chiral anomaly. We perform a $2+1$-flavor lattice QCD calculation and demonstrate that the two-point function of a gluonically defined topological charge density after a short Yang-Mills gradient flow contains the propagation of the ${\eta }^{\prime }$ meson, by showing that its mass in the chiral and continuum limit is consistent with the experimental value. The gluonic correlator does not suffer from the contamination of the pion contribution, and the clean signal is obtained at significantly lower numerical cost compared to the conventional method with the quark bilinear operators.

We study the ground state and the first three radially excited states of a self-gravitating Bose-Einstein condensate with respect to the influence of two external parameters, the total mass and the strength of interactions between particles. For this we use the so-called Gross-Pitaevskii-Newton system. In this context we especially determine the case of very high total masses where the ground state solutions of the Gross-Pitaevskii-Newton system can be approximated with the Thomas-Fermi limit. Furthermore, stability properties of the computed radially excited states are examined by applying arguments of the catastrophe theory.

We examine gravitational wave asteroseismology relations for $f$-modes of rapidly rotating neutron stars. A different approach than previous studies is employed. First, the moment of inertia is used instead of the stellar radius and, second, the normalization of the oscillation frequencies and damping times is different. It is shown that in the nonrotating case this can lead to a much stronger equation of state independence, and our goal is to generalize the static relations to the rapidly rotating case and values of the spherical mode number $l\ge 2$. We employ realistic equations of state that cover a very large range of stiffness in order to better check the universality of the relations. We later explore the inverse problem; i.e., we obtain the neutron star parameters from the observed gravitational frequencies and damping times. It turns out that, with this new set of relations, we can solve the inverse problem with very good accuracy using three frequencies. This was not possible in the previous studies, where one also needed damping times. The asteroseismology relations are also quite accurate for the massive rapidly rotating models that are subject to secular instabilities.

We express the in-in functional determinant giving the one-loop effective potential for a scalar field propagating in a cosmological spacetime in terms of the mode functions specifying the vacuum of the theory and then apply adiabatic regularization to make this bare potential finite. In this setup, the adiabatic regularization offers a particular renormalization prescription that isolates the effects of the cosmic expansion. We apply our findings to determine the radiative corrections to the classical inflaton potentials in scalar field inflationary models and also we derive an effective potential for the superhorizon curvature perturbation $\zeta$ encoding its scatterings with the subhorizon modes. Although the resulting modifications to the cosmological observables like non-Gaussianity turn out to be small, they distinctively appear after horizon crossing.

The decay rate of the Higgs decay $H\to Z\gamma$ is evaluated at the one-loop level in the $SO(5)\times U(1)$ gauge-Higgs unification. Although an infinite number of loops with Kaluza-Klein states contribute to the decay amplitude, there appears the cancellation among the loops, and the decay rate is found to be finite and nonzero. It is found that the decay rate is well approximated by the decay rate in the standard model multiplied by ${\cos }^2{\theta }_H$, where ${\theta }_H$ is the Aharonov-Bohm phase induced by the vacuum expectation value of an extra-dimensional component of the gauge field.

We investigate the Gubser solution of viscous hydrodynamics at finite density and analytically compute the flow harmonics $v_n$. We explicitly show how $v_n$ and their viscous corrections depend on the chemical potential. The difference in $v_n$ between particles and antiparticles is also analytically computed and shown to be proportional to various chemical potentials and the viscosity. Excellent agreement is obtained between the results and the available experimental data from the SPS, RHIC and the LHC.

The underlying mixing of quark components of scalar mesons is probed in $\pi K$ scattering within a generalized linear sigma model that contains two scalar meson nonets and two pseudoscalar meson nonets (a quark-antiquark and a four-quark). In the leading order of this model, all free parameters have been previously fixed using the mass spectra and several low-energy parameters known from experiment and consistent predictions have been made. As in other predictions of the model, in the present work the isospins $I=1/2$, $3/2$ and $J=0$ projection of the $\pi K$ scattering amplitude (as well as phase shifts) are computed and compared with experiment. In the $I=1/2$ channel, it is shown that within the uncertainties of the model parameters a good agreement with experimental data up to an energy of about 1 GeV is obtained, whereas in the $I=3/2$ channel there is a better agreement with experiment which extends to about 1.4 GeV. The effect of final state interactions of $\pi K$ in the $I=1/2$ channel is approximated by the K-matrix method and the poles of the unitarized scattering amplitude are found. It is shown that the model predicts a light and broad kappa resonance with a mass and decay width of 670–770 MeV and 640–750 MeV consistent with other prior works. Moreover, the scattering lengths in the $I=1/2$, $3/2$ are also computed and shown to qualitatively agree with experiment. The overall predictions presented here further support previous findings that the scalar mesons below and above 1 GeV have substantial underlying mixings and that those below 1 GeV have dominant four-quark substructures while those above 1 GeV are closer to conventional $P$-wave quark-antiquark states.

One of the most important problems in any conformal field theory is the calculation of three-point functions of primary operators. In this paper we provide explicit examples of correlators with two scalar operators in $\mathcal{N}=4$ super-Yang-Mills theory at large $N$, corresponding to pulsating semiclassical strings in ${\mathrm{AdS}}_5\times S^5$, and an operator with small quantum numbers at strong coupling.

A novel nonlocal four-photon interaction on the deformed spacetime is derived and studied in the three selected models (I, II, III). The first two models (I, II) are obtained via two distinct second-order $\theta$-exact Seiberg-Witten maps of the noncommutative U(1) gauge field strength on Moyal space. The third one (III), inspired by the manifestly gauge invariant structures emerging in the first two, due to the model generality has been constructed with a different set of freedom parameters. The physical relevancy of all models is analyzed by evaluating the four-photon-tadpole diagram, which, when combined with the bubble graph, enables us to fully consider all contributions to the one-loop photon polarization tensor. For an arbitrary noncommutative matrix ${\theta }^{\mu \nu }$, the full quadratic IR divergence cancellation in the one-loop photon two-point function is obtained with particular combinations of Seiberg-Witten map/gauge-symmetry freedom parameters in models I and II. Finally, our model III enables complete elimination of all pathological terms in the photon polarization tensor at one-loop order if a special value for the $\theta$ matrix is chosen.

We show that when graphene is only subject to strain, the spin connection gauge field that arises plays no measurable role, but when intrinsic curvature is present and strain is small, spin connection dictates most of the physics. We do so by showing that the Weyl field associated with strain is a pure gauge field and no constraint on the ($2+1$)-dimensional spacetime appears. On the other hand, for constant intrinsic curvature that also gives a pure gauge Weyl field, we find a classical manifestation of a quantum Weyl anomaly, descending from a constrained spacetime. We are in the position to do this because we find the equations that the conformal factor in ($2+1$) dimensions has to satisfy, which is a nontrivial generalization to ($2+1$) dimensions of the classic Liouville equation of the differential geometry of surfaces. Finally, we comment on the peculiarities of the only gauge field that can describe strain, the well-known pseudogauge field $A_1\sim u_{11}-u_{22}$ and $A_2\sim u_{12}$, and conclude by offering some scenarios in fundamental physics that this peculiar field could help to realize.

We derive the most general effective low-energy potential to order $O(1/m)$ for slow Dirac fermions with mass $m$, coupled to gravitational, chameleon and torsion fields in the Einstein-Cartan gravity. The obtained results can be applied to the experimental analysis of gravitational, chameleon and torsion interactions in terrestrial laboratories. We discuss the use of rotating coordinate systems, caused by rotations of devices, for measurements of the torsion vector and tensor components, caused by minimal torsion-fermion couplings [A. N. Ivanov and M. Wellenzohn, Phys. Rev. D 92, 065006 (2015)]. Using the most general form of a metric tensor of curved spacetimes in rotating coordinate systems, proposed by Obukhov, Silenko, and Teryaev [Phys. Rev. D 84, 024025 (2011)], we extend this metric by the inclusion of the chameleon field and calculate the set of vierbein fields, in terms of which Dirac fermions couple to the torsion vector and tensor components through minimal torsion-fermion couplings. For such a set of vierbein fields we discuss a part of the effective low-energy potential for slow Dirac fermions, coupled to gravitational, chameleon and torsion fields to order $O(1)$ in the large fermion mass expansion.

The possibility of treating boundary conditions in terms of a bilocal dynamical field is formalized in terms of a boundary action. This allows for a simple path-integral perturbation theory approach to physical effects such as radiation from a time-dependent boundary. The nature of the action which governs the dynamics of the bilocal field is investigated for a limited case (which includes the Robin boundary conditions).