In this work we investigate the consequences of the Lorentz symmetry violation on extremely long-lived, time-dependent, and spatially localized field configurations, named oscillons. This is accomplished for two interacting scalar field theories in ($D+1$) dimensions in the context of the so-called standard model extension. We show that $D$-dimensional scalar field lumps can present a typical size $R_{\min }\ll R_{\mathrm{KK}}$, where $R_{\mathrm{KK}}$ is the extent of extra dimensions in Kaluza-Klein theories. The size $R_{\min }$ is shown to strongly depend upon the terms that control the LV of the theory. This implies either contraction or dilation of the average radius $R_{\min }$, and a new rule for its composition, likewise. Moreover, we show that the spatial dimensions for existence of oscillating lumps have an upper limit, opening new possibilities to probe the existence of $D$-dimensional oscillons at TeV energy scale. In addition, in a cosmological scenario with Lorentz symmetry breaking, we show that in the early Universe with an extremely high energy density and a strong LV, the typical size $R_{\min }$ was highly dilated. As the Universe had expanded and cooled down, it then passed through a phase transition toward a Lorentz symmetry, wherein $R_{\min }$ tends to be compact.

We use a recent result for the graviton contribution to the one-loop vacuum polarization to solve the effective field equations for dynamical photons on a de Sitter background. Our results show that the electric field experiences a secular enhancement proportional to the number of inflationary $e$-foldings. We discuss the minimum effect this establishes for primordial inflation to seed cosmic magnetic fields.

We formulate new general-relativistic extensions of Newtonian rotation laws for self-gravitating stationary fluids. They have been used to rederive, in the first post-Newtonian approximation, the well-known geometric dragging of frames. We derive two other general-relativistic weak-field effects within rotating tori: the recently discovered dynamic antidragging and a new effect that measures the deviation from the Keplerian motion and/or the contribution of the fluids self-gravity. One can use the rotation laws to study the uniqueness and the convergence of the post-Newtonian approximations as well as the existence of the post-Newtonian limits.

The statistical response of a Kerr black hole to incoming quantum radiation has heretofore been studied by the methods of maximum entropy or quantum field theory in curved spacetime. Neither approach pretends to take into account the quantum structure of the black hole itself. To address this last issue we calculate here the conditional probability distribution associated with the hole’s response by assuming that the horizon area has a discrete quantum spectrum, and that its quantum evolution corresponds to jumps between adjacent area eigenvalues, possibly occurring in series, with consequent emission or absorption of quanta, possibly in the same mode. This “atomic model” of the black hole is implemented in two different ways and recovers the previously calculated radiation statistics in both cases. The corresponding conditional probability distribution is here expressed in closed form in terms of a hypergeometric function.

We revisit astrophysical constraints on models with an ultralight gravitino, in particular extending the analysis to more general models and the case of $R$-parity breaking. These constraints allow us to restrict the value of the gravitino mass depending on the masses of scalar moduli. We perform both a frequentist and a Bayesian analysis and we find comparable results, even if the Bayesian analysis is in part affected by volume effects. Only a small window of gravitino masses can be excluded by the supernova constraints in a model-independent way, while limits obtained with a definite assumption on the scalar masses are more stringent.

A short inflationary phase may not erase all traces of the primordial Universe. Associated observables include both spatial curvature and “anomalies” in the microwave background or large-scale structure. The present curvature ${\mathrm{\Omega }}_{K,0}$ reflects the initial curvature, ${\mathrm{\Omega }}_{K,\text{start}}$, and the angular size of anomalies depends on $k_{\text{start}}$, the comoving horizon size at the onset of inflation. We estimate posteriors for ${\mathrm{\Omega }}_{K,\text{start}}$ and $k_{\text{start}}$ using current data and simulations, and show that if either quantity is measured to have a nonzero value, both are likely to be observable. Mappings from ${\mathrm{\Omega }}_{K,\text{start}}$ and $k_{\text{start}}$ to present-day observables depend strongly on the primordial equation of state; ${\mathrm{\Omega }}_{K,0}$ spans 10 orders of magnitude for a given ${\mathrm{\Omega }}_{K,\text{start}}$, while a simple and general relationship connects ${\mathrm{\Omega }}_{K,0}$ and $k_{\text{start}}$. We show that current bounds on ${\mathrm{\Omega }}_{K,0}$ imply that if $k_{\text{start}}$ is measurable, the curvature was already small when inflation began. Finally, since the energy density changes slowly during inflation, primordial gravitational wave constraints require that a short inflationary phase be preceded by a nontrivial preinflationary phase with critical implications for the expected value of ${\mathrm{\Omega }}_{K,\text{start}}$.

Models addressing the naturalness of a light Higgs boson typically employ symmetries, either bosonic or fermionic, to stabilize the Higgs mass. We consider a setup with the minimal amount of symmetries: four shift symmetries acting on the four components of the Higgs doublet, subject to the constraints of linearly realized $SU(2{)}_L\times U(1{)}_Y$ electroweak symmetry. Up to terms that explicitly violate the shift symmetries, the effective Lagrangian can be derived, irrespective of the spontaneously broken group $G$ in the ultraviolet, and is universal among all models where the Higgs arises as a pseudo-Nambu-Goldstone boson. Very high energy scatterings of vector bosons could provide smoking gun signals of a minimally symmetric Higgs boson.

Composite Higgs models are intriguing scenarios in which the Higgs particle is identified as a pseudo-Nambu–Goldstone boson associated with spontaneous breaking of some global symmetry above the electroweak scale. They would predict new resonances at high-energy scales, some of which can appear at multi-TeV scales. In such a case, analogies with the pion physics in QCD, where a sizable phase shift is predicted in pion-pion scattering processes, might help us to evaluate scales of the resonances. In this paper, we discuss two complementary approaches to investigate the compositeness scale in minimal composite Higgs models. First, we discuss the bound on vector boson scattering from perturbative unitarity, and we evaluate the phase shift of the scattering amplitude, assuming that the same fitting function as one in the case of the pion physics can be applied. We then obtain the relation between possible phase shifts and promising new resonance scales. We also investigate the possibility to measure the phase shift at LHC and the future hadron colliders. Second, we classify deviations in Higgs coupling constants from the standard model predictions in various kinds of the minimal composite Higgs models. We then discuss a possibility to discriminate a specific minimal composite Higgs model from the other models with extended Higgs sectors by utilizing deviation patterns in the Higgs boson couplings by future precision measurements.

We investigate contributions of Kaluza-Klein (KK) graviton in extra dimension models to the process $pp\to p\gamma p\to p\gamma jX$, where a proton emits a quasireal photon and is detected by using the very forward detectors planned at the LHC. In addition to the $\gamma q$ initial state as in the Compton scattering in the standard model, the $\gamma g$ scattering contributes through the $t$-channel exchange of KK gravitons. Taking account of pileup contributions to the background and examining viable kinematical cuts, constraints on the parameter space of both the ADD (Arkani-Hamed, Dimopoulos and Dvali) model and the RS (Randall and Sundrum) model are studied. With $200{\mathrm{fb}}^{-1}$ data at a center-of-mass energy of 14 TeV, the expected lower bound on the cutoff scale for the ADD model is 6.3 TeV at 95% confidence level, while a lower limit of 2.0 (0.5) TeV is set on the mass of the first excited graviton with the coupling parameter $k/{\overline{M}}_{\text{Pl}}=0.1(0.01)$ for the RS model.

We look into the signatures of the effective Y-bosonic strings in the gluonic profile due to a system of three static quarks on the lattice. The color field is calculated in pure SU(3) Yang-Mills lattice gauge theory at finite temperature with Polyakov loop operators. The analysis of the action density unveils a filled-$\mathrm{\Delta }$ distribution. However, we found that these $\mathrm{\Delta }$-shaped action density profiles are structured from three Y-shaped Gaussian-like flux tubes. The geometry of the Y-shaped Gaussian flux tubes changes according to the quark configuration and temperature. The lattice data for the mean-square width of the gluonic action density have been compared to the corresponding width calculated based on the string model at finite temperature. We assume Y-string configuration with minimal length. The growth pattern of the action density of the gluonic field fits to junction fluctuations of the Y-baryonic string model for large quark separation at the considered temperatures.

The production of a $D\overline{D}$ meson pair in antiproton-proton ($\overline{p}p$) annihilation close to the production threshold is investigated, with special emphasis on the role played by the $\psi (3770)$ resonance. The study is performed in a meson-baryon model where the elementary charm production process is described by baryon exchange. Effects of the interactions in the initial and final states are taken into account rigorously, where the latter involves also those due to the $\psi (3770)$. The predictions for the $D\overline{D}$ production cross section are in the range of 30–250 nb, and the contribution from the $\psi (3770)$ resonance itself amounts to roughly 20–80 nb.

We evaluate the $e^{-}{e}^{+}\to e^{-}{e}^{+}+h$ process through the $ZZ$ fusion channel at the International Linear Collider operating at 500 GeV and 1 TeV center-of-mass energies. We perform realistic simulations on the signal process and background processes. With judicious kinematic cuts, we find that the inclusive cross section can be measured to 2.9% after combining the 500 GeV at $500{\mathrm{fb}}^{-1}$ and 1 TeV at $1{\text{ab}}^{-1}$ runs. A multivariate log-likelihood analysis further improves the precision of the cross section measurement to 2.3%. We discuss the overall improvement to model-independent Higgs width and coupling determinations and demonstrate the use of different channels in distinguishing new physics effects in Higgs physics. Our study demonstrates the importance of the $ZZ$ fusion channel to Higgs precision physics, which has often been neglected in the literature.

We search for the decay $B^{+}\to {\ell }^{+}{\nu }_{\ell }\gamma$ with ${\ell }^{+}=e^{+}$ or ${\mu }^{+}$ using the full Belle data set of $772\times {10}^{6}B\overline{B}$ pairs, collected at the $\mathrm{{\rm Y}}(4\mathrm{S})$ resonance with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider. We reconstruct one $B$ meson in a hadronic decay mode and search for the $B^{+}\to {\ell }^{+}{\nu }_{\ell }\gamma$ decay in the remainder of the event. We observe no significant signal within the phase space of $E_{\gamma }^{\text{sig}}>1\mathrm{GeV}$ and obtain upper limits of $\mathcal{B}(B^{+}\to e^{+}{\nu }_e\gamma )<6.1\times {10}^{-6}$, $\mathcal{B}(B^{+}\to {\mu }^{+}{\nu }_{\mu }\gamma )<3.4\times {10}^{-6}$, and $\mathcal{B}(B^{+}\to {\ell }^{+}{\nu }_{\ell }\gamma )<3.5\times {10}^{-6}$ at 90% credibility level.

Neutrinos propagating in media (matter and electromagnetic fields) undergo flavor and helicity oscillations, where helicity transitions are instigated both by electromagnetic fields and matter currents. In addition, it has been shown that correlations between neutrinos and antineutrinos of opposite momentum can build up in anisotropic media. We rederive the neutrino equations of motion in the mean-field approximation for homogeneous yet anisotropic media, confirming previous results except for a small correction in the Majorana case. Furthermore, we derive the mean-field Hamiltonian induced by neutrino electromagnetic interactions. We also provide a phenomenological discussion of pair correlations in comparison with helicity correlations.

Asymmetric symmetry breaking models dynamically break the $G\times G$ gauge symmetries of mirror models to distinct subgroups in the two sectors. The coincidental abundances of visible and dark matter, ${\mathrm{\Omega }}_{\mathrm{DM}}\simeq 5{\mathrm{\Omega }}_{\mathrm{VM}}$, motivates asymmetric dark matter theories where similar number densities of baryons in each sector are explained by their connected origins. However, the question of why the baryons of two sectors should have similar mass remains. In this work we develop an alternative class of asymmetric symmetry breaking models which unify the dark and visible sectors while generating a small difference in the mass scale of the baryons of each sector. By examining the different paths that the SO(10) GUT group can take in breaking to gauge symmetries containing SU(3), we can adapt the mechanism of asymmetric symmetry breaking to demonstrate models in which originally unified visible and dark sectors have isomorphic color gauge groups at low energy yet pass through different intermediate gauge groups at high energy. Through this, slight differences in the running coupling evolutions and, thus, the confinement scales of the two sectors are generated.

We discuss the relation between functional renormalization group (FRG) and local renormalization group (LRG), focusing on the two-dimensional case as an example. We show that away from criticality the Wess-Zumino action is described by a derivative expansion with coefficients naturally related to RG quantities. We then demonstrate that the Weyl consistency conditions derived in the LRG approach are equivalent to the RG equation for the $c$ function available in the FRG scheme. This allows us to give an explicit FRG representation of the Zamolodchikov-Osborn metric, which in principle can be used for computations.

We analyze critically the renormalization of quantum fields in cosmological spacetimes, using noncovariant ultraviolet cutoffs. We compute explicitly the counterterms necessary to renormalize the semiclassical Einstein equations, using comoving and physical ultraviolet cutoffs. In the first case, the divergences renormalize bare conserved fluids, while in the second case it is necessary to break the covariance of the bare theory. We point out that, in general, the renormalized equations differ from those obtained with covariant methods, even after absorbing the infinities and choosing the renormalized parameters to force the consistency of the renormalized theory. We repeat the analysis for the evolution equation for the mean value of an interacting scalar field.

The choice of the area operator in loop quantum gravity is by no means unique. In addition to the area operator commonly used in loop quantum gravity there is also an area operator introduced by Krasnov in 1998, which gives uniformly spaced area spectra for the horizons of spacetime. Using Krasnov’s area operator we consider the thermodynamics of spherically symmetric spacetimes equipped with horizons in loop quantum gravity. Among other things, our approach implies, in a pretty simple manner, that every horizon of spacetime emits thermal radiation and possesses entropy which, in the natural units, is one-quarter of its area. When applied to the de Sitter spacetime loop quantum gravity provides an explanation both to the presence and the smallness of the cosmological constant.

In Hořava and Einstein-aether theories of modified gravity, in spite of the violation of Lorentz invariance, spherically symmetric stationary black hole solutions possess an inner universal horizon which separates field configurations into two disconnected classes. We compute the late time radiation emitted by a dispersive field propagating in such backgrounds. We fix the initial conditions on stationary modes by considering a regular collapsing geometry, and by imposing that the state inside the infalling shell is the vacuum. We find that the mode pasting across the shell is adiabatic at late time (large inside frequencies). This implies that large black holes emit a thermal flux with a temperature fixed by the surface gravity of the Killing horizon. In turn, this suggests that the universal horizon should play no role in the thermodynamical properties of these black holes.

In this paper, we study small-scale fluctuations (baryon pressure sound waves) in the baryon fluid during recombination. In particular, we look at their evolution in the presence of relative velocities between baryons and photons on large scales ($k\sim 10^{-1}{\mathrm{Mpc}}^{-1}$), which are naturally present during the era of decoupling. Previous work concluded that the fluctuations grow due to an instability of sound waves in a recombining plasma, but that the growth factor is small for typical cosmological models. These analyses model recombination in an inhomogenous universe as a perturbation to the parameters of the homogenous solution. We show that for relevant wave numbers $k\gtrsim 10^3{\mathrm{Mpc}}^{-1}$ the dynamics are significantly altered by the transport of both ionizing continuum ($h\nu >13.6\mathrm{eV}$) and Lyman-$\alpha$ photons between crests and troughs of the density perturbations. We solve the radiative transfer of photons in both these frequency ranges and incorporate the results in a perturbed three-level atom model. We conclude that the instability persists at intermediate scales. We use the results to estimate a distribution of growth rates in $10^7$ random realizations of large-scale relative velocities. Our results indicate that there is no appreciable growth; out of these $10^7$ realizations, the maximum growth factor we find is less than $\approx 1.2$ at wave numbers of $k\approx 10^3{\mathrm{Mpc}}^{-1}$. The instability’s low growth factors are due to the relatively short duration of the recombination epoch during which the electrons and photons are coupled.