We consider ($0+1$) and ($1+1$) dimensional Yukawa theory in various scalar field backgrounds, which are solving classical equations of motion: ${\ddot{\varphi }}_{\mathrm{cl}}=0$ or $\square {\varphi }_{\mathrm{cl}}=0$, correspondingly. The ($0+1$)–dimensional theory we solve exactly. In ($1+1$)–dimensions we consider background fields of the form ${\varphi }_{\mathrm{cl}}=Et$ and ${\varphi }_{\mathrm{cl}}=Ex$, which are inspired by the constant electric field. Here $E$ is a constant. We study the backreaction problem by various methods, including the dynamics of a coherent state. We also calculate loop corrections to the correlation functions in the theory using the Schwinger–Keldysh diagrammatic technique.

Ginzburg-Landau vortices in superconductors attract or repel depending on whether the value of the coupling constant $\lambda$ is less than 1 or larger than 1. At critical coupling $\lambda =1$, it was previously observed that a strongly localized magnetic impurity behaves very similarly to a vortex. This remains true for axially symmetric configurations away from critical coupling. In particular, a delta function impurity of a suitable strength is related to a vortex configuration without impurity by singular gauge transformation. However, the interaction of vortices and impurities is more subtle and depends not only on the coupling constant $\lambda$ and the impurity strength, but also on how broad the impurity is. Furthermore, the interaction typically depends on the distance and may be attractive at short distances and repulsive at long distances. Numerical simulations confirm moduli space approximation results for the scattering of one and two vortices with an impurity. However, a double vortex will split up when scattering with an impurity, and the direction of the split depends on the sign of the impurity. Head-on collisions of a single vortex with different impurities away from critical coupling are also briefly discussed.

Clustering properties and peculiar velocities of halos in large-scale structure carry a wealth of cosmological information over a wide range of scales from linear to nonlinear scales. We use halo catalogs in a suite of high-resolution $N$-body simulations to construct mock catalogs of galaxies that resemble the Sloan Digital Sky Survey (SDSS)-like luminous early type galaxies at three redshift bins in the range $0.15\le z\le 0.7$. To do this, we include ten nuisance parameters to model variations in halo-galaxy connections for each redshift bin, the halo occupation distribution, and the spatial and velocity distributions of galaxies in the host halos. We evaluate the Fisher information matrix for the redshift-space power spectrum of SDSS-like galaxies using different sets of the mock catalogs that are generated from changes in each of model parameters, cosmological parameters (${\sigma }_8$ and ${\mathrm{\Omega }}_{\mathrm{m}}$), the halo-galaxy connection parameters, and the cosmological distances ($D_{\mathrm{A}}$ and $H$ parameters at each redshift bin) for modeling an apparent geometrical distortion of the redshift-space power spectrum (the Alcock-Paczynski effect). We show that combining the monopole and quadrupole power spectra of galaxies allows for precise estimations of the cosmological parameters and the cosmological distances, even after marginalization over the halo-galaxy parameters, by lifting the parameter degeneracies that are otherwise inevitable if either of the two spectra alone is used. When including the galaxy power spectrum information up to $k=0.3h{\mathrm{Mpc}}^{-1}$, we find about factor of 6 gain in the cosmological information content of (${\sigma }_8$, ${\mathrm{\Omega }}_{\mathrm{m}}$, $D_{\mathrm{A}}$’s, and $H$’s) compared to $k=0.2h{\mathrm{Mpc}}^{-1}$. We also discuss the use of redshift-space galaxy power spectrum for a model-independent measurement of redshift-space distortion strength and a possible impact of the assembly bias on the cosmological parameters.

Recent observations of the cosmic microwave background (CMB) indicate that a successful theory of cosmological inflation needs to have flat potential of the inflaton scalar field. Realizing the inflaton to be a pseudo-Nambu Goldstone boson (pNGB) could ensure the flatness and the sub-Planckian scales related to the dynamics of the paradigm. In this work, we have taken the most general form of such a scenario: Goldstone inflation proposed in [D. Croon, V. Sanz, and J. Setford, J. High Energy Phys. 10 (2015) 020] and studied the model in the noncanonical domain. Natural inflation is a limiting case of this model, which is also studied here in the noncanonical regime. Our result is compared with the recent release by Planck collaboration and it is shown that for some combination of the model parameters, a Goldstone inflationary model in the noncanonical realization obeys the current observational bounds. Then, we studied the era of reheating after the end of inflation. For different choice of model parameters, constraints on the reheating temperature ($T_{\mathrm{re}}$) and number of e-folds during reheating($N_{\mathrm{re}}$) for the allowed inflationary observables [e.g., scalar spectral index($n_s$) and tensor to scalar ratio($r$)] are predicted for this model.

One of the challenging questions in cosmology is the nature of dark matter particles. Fuzzy dark matter (FDM) is one of the candidates which is made of very light ($m_{\mathrm{FDM}}\simeq {10}^{-22}–{10}^{-21}\mathrm{eV}$) bosonic particles with no self-interaction. It is introduced by the motivation to solve the core-cusp problem in the galactic halos. In this work, we investigate the observational features from FDM halo collisions. Taking into account the quantum wavelength of the condensed bosonic structure, we determine the interference of the wave function of cores after collision. The fringe formation in the wave function is associated to the density contrast of the dark matter inside the colliding galaxies. The observational signatures of the fringes of the distribution of the dark matter are (i) on the lensing of the background sources, (ii) accumulation of the baryonic plasma tracking the interference of the FDM potential and (iii) excess in the x-ray emission from dense regions. Finally, we provide prospects for the observations of quantum wave features of FDM in the colliding galaxies. The NGC6240 colliding galaxy at the redshift of $z=0.024$ is a suitable candidate for this study. No signal is detected from the fringes in the Chandra data and taking into account the angular resolution of the telescope, we put a constraint of $m>7\times {10}^{-23}\mathrm{eV}$ on the mass of FDM particles.

If the symmetry breaking leading to the origin of the axion dark matter field occurs after the end of inflation and is never restored, then overdensities in the axion field collapse to form dense objects known in the literature as axion miniclusters. The estimates of the typical minicluster mass and radius strongly depend on the details of the cosmology at which the onset of axion oscillations begin. In this work we study the properties and phenomenology of miniclusters in alternative cosmological histories and find that they can change by many orders of magnitude. Our findings have direct implications on current and future experimental searches and, in the case of discovery, could be used to learn something about the universe expansion prior to big bang nucleosynthesis.

Neutrinos emitted deep within a supernova explosion experience a self-induced index of refraction. In the stationary, one-dimensional (1D) supernova “bulb model,” this self-induced refraction can lead to a collective flavor transformation which is coherent among different neutrino momentum modes. Such collective oscillations can produce partial swaps of the energy spectra of different neutrino species as the neutrinos stream away from the proto-neutron star. However, it has been demonstrated that the spatial symmetries (such as the spherical symmetry in the bulb model) can be broken spontaneously by collective neutrino oscillations in multidimensional models. Using a stationary, 2D neutrino ring model we demonstrate that there exist two limiting scenarios where collective oscillations may occur. In one limit, the collective flavor transformation begins at a radius with relatively high neutrino densities and develops small-scale flavor structures. The loss of the spatial correlation in the neutrino flavor field results in similar (average) energy spectra for the antineutrinos of almost all energies and the neutrinos of relatively high energies. In the other limit, the flavor transformation starts at a radius where the neutrino densities are smaller (e.g., due to the suppression of the high matter density near the proto-neutron star). Although the spatial symmetry is broken initially, it is restored as the neutrino densities decrease, and the neutrinos of different flavors partially swap their energy spectra as in the 1D bulb model. This finding may have interesting ramifications in other aspects of supernova physics.

Data from the Gaia satellite show that the solar neighborhood of the Milky Way’s stellar halo is imprinted with substructure from several accretion events. Evidence of these events is found in “the shards,” stars clustering with high significance in both action space and metallicity. Stars in the shards share a common origin, likely as ancient satellite galaxies of the Milky Way, so will be embedded in dark matter (DM) counterparts. These “dark shards” contain two substantial streams (S1 and S2), as well as several retrograde, prograde and lower energy substructures. The retrograde stream S1 has a very high Earth-frame speed of $\sim 550\mathrm{km}{\mathrm{s}}^{-1}$ while S2 moves on a prograde, but highly polar orbit and enhances the peak of the speed distribution at around $300\mathrm{km}{\mathrm{s}}^{-1}$. The presence of the dark shards locally leads to modifications of many to the fundamental properties of experimental DM signals. The S2 stream in particular gives rise to an array of effects in searches for axions and in the time dependence of nuclear recoils: shifting the peak day, inducing nonsinusoidal distortions, and increasing the importance of the gravitational focusing of DM by the Sun. Dark shards additionally bring new features for directional signals, while also enhancing the DM flux toward Cygnus.

We use 7 years of electron and positron Fermi-LAT data to search for a possible excess in the direction of the Sun in the energy range from 42 GeV to 2 TeV. In the absence of a positive signal we derive flux upper limits which we use to constrain two different dark matter (DM) models producing $e^{+}{e}^{-}$ fluxes from the Sun. In the first case we consider DM model being captured by the Sun due to elastic scattering and annihilation into $e^{+}{e}^{-}$ pairs via a long-lived light mediator that can escape the Sun. In the second case we consider instead a model where DM density is enhanced around the Sun through inelastic scattering and the DM annihilates directly into $e^{+}{e}^{-}$ pairs. In both cases we perform an optimal analysis, searching specifically for the energy spectrum expected in each case, i.e., a boxlike shaped and linelike shaped spectrum respectively. No significant signal is found and we can place limits on the spin-independent cross section in the range from ${10}^{-46}{\mathrm{cm}}^2$ to ${10}^{-44}{\mathrm{cm}}^2$ and on the spin-dependent cross section in the range from ${10}^{-43}{\mathrm{cm}}^2$ to ${10}^{-41}{\mathrm{cm}}^2$. In the case of inelastic scattering the limits on the cross section are in the range from ${10}^{-43}{\mathrm{cm}}^2$ to ${10}^{-41}{\mathrm{cm}}^2$. The limits depend on the life time of the mediator (elastic case) and on the mass splitting value (inelastic case), as well as on the assumptions made for the size of the deflections of electrons and positrons in the interplanetary magnetic field.

We present the results of an all-sky search for continuous gravitational wave signals with frequencies in the 200–600 Hz range and frequency derivative (spindown) from $-1\times {10}^{-8}$ through $1.11\times {10}^{-9}\mathrm{Hz}/\mathrm{s}$. Together with the results from [ Phys. Rev. Lett. 123, 101101 (2019)], this search completes the all-sky survey for frequencies between 20 to 600 Hz on O1 data. It also demonstrates the scalability of our search on a parameter space 26 times larger than previously considered. The results presented here complement the LIGO O2 data results [ Phys. Rev. Lett. 123, 171101 (2019), Phys. Rev. D 100, 024004 (2019)] with comparable when not better sensitivity and do not rely on data with irregularities in the noise-subtraction procedure. We establish strict upper limits which hold for worst-case signal parameters and dedicated upper limits for generic $\approx 0$ spindown signals, such as those expected from boson condensates around black holes.

We find in one-loop calculations and spectator models that twist-3 generalized parton distributions exhibit discontinuities. In the forward limit, these discontinuities grow into Dirac delta functions which are essential to satisfy the sum rules involving twist-3 parton distribution functions (PDFs). We calculate twist-3 quasi-PDFs as a function of longitudinal momentum and identify the Dirac delta function terms with momentum components in the nucleon state that do not scale as the nucleon is boosted to the infinite momentum frame.

We present a direct computation of the full color two-loop five-point all-plus Yang-Mills amplitude using four dimensional unitarity and recursion. We present the $SU(N_c)$ amplitudes in compact analytic forms. Our results match the explicit expressions previously computed but do not require full two-loop integral methods.

The density of state approach has recently been proposed as a potential route to circumvent the sign problem in systems at finite density. In this study, using the linear logarithmic relaxation (LLR) algorithm, we extract the generalized density of states, which is defined in terms of the imaginary part of the action, for the self-interacting relativistic lattice Bose gas at finite density. After discussing the implementation and testing the reliability of our approach, we focus on the determination of the free energy difference between the full system and its phase-quenched counterpart. Using a set of lattices ranging from $4^4$ to ${16}^4$, we show that in the low density phase, this overlap free energy can be reliably extrapolated to the thermodynamic limit. The numerical precision we obtain with the LLR method allows us to determine with sufficient accuracy the expectation value of the phase factor, which is used in the calculation of the overlap free energy, down to values of $\mathcal{O}({10}^{-480})$. When phase factor measurements are extended to the dense phase, a change of behavior of the overlap free energy is clearly visible as the chemical potential crosses a critical value. Using fits inspired by the approximate validity of mean-field theory, which is confirmed by our simulations, we extract the critical chemical potential as the nonanalyticity point in the overlap free energy, obtaining a value that is in agreement with other determinations. Implications of our findings and potential improvements of our methodology are also discussed.

In this paper, we calculate the inclusive rate of $W^{+}{W}^{-}$ pair production through leptonic decay channels $W^{+}{W}^{-}\to l^{+}{\nu }_l+l^{\prime -}{\nu }_{l^{\prime }}$ in the $k_t$-factorization framework. We also consider the exclusive $W^{+}{W}^{-}$ pair production through the one-loop induced $gg\to H\to W^{+}{W}^{-}$ channel that is important for the study of new physics beyond the Standard Model. The results are compared with predictions from the Herwig 7 event generator in the collinear factorization framework and with the experimental data from the ATLAS and the CMS collaborations. It will be shown that our predictions for the $W^{+}{W}^{-}$ boson pair production signals are in agreement with the experimental data as well as the collinear results.

A search for decay-time-dependent charge-parity ($CP$) asymmetry in $D^0\to K^{+}{K}^{-}$ and $D^0\to {\pi }^{+}{\pi }^{-}$ decays is performed at the LHCb experiment using proton-proton collision data recorded at a center-of-mass energy of 13 TeV, and corresponding to an integrated luminosity of $5.4{\text{fb}}^{-1}$. The $D^0$ mesons are required to originate from semileptonic decays of $b$ hadrons, such that the charge of the muon identifies the flavor of the neutral $D$ meson at production. The asymmetries in the effective decay widths of $D^0$ and ${\overline{D}}^0$ mesons are determined to be $A_{\mathrm{\Gamma }}(K^{+}{K}^{-})=(-4.3\pm 3.6\pm 0.5)\times 10^{-4}$ and $A_{\mathrm{\Gamma }}({\pi }^{+}{\pi }^{-})=(2.2\pm 7.0\pm 0.8)\times 10^{-4}$, where the uncertainties are statistical and systematic, respectively. The results are consistent with $CP$ symmetry and, when combined with previous LHCb results, yield $A_{\mathrm{\Gamma }}(K^{+}{K}^{-})=(-4.4\pm 2.3\pm 0.6)\times 10^{-4}$ and $A_{\mathrm{\Gamma }}({\pi }^{+}{\pi }^{-})=(2.5\pm 4.3\pm 0.7)\times 10^{-4}$.

We elucidate a cancellation mechanism for the electric dipole moment of the electron in the general two Higgs doublet model. The impressive improvement by the ACME Collaboration in 2018 suggests the presence of a new electron Yukawa coupling that brings in exquisite cancellations among dangerous diagrams, broadening the solution space for electroweak baryogenesis driven by an extra top Yukawa coupling. The cancellation mechanism calls for the new Yukawa couplings to have hierarchical structures that echo the observed pattern of the Standard Model Yukawa couplings.

One of the most triumphant predictions of the theory of general relativity was the recent LIGO-Virgo detection of gravitational-wave (GW) signals produced in binary black hole (BH) mergers. However, it is suggested that exotic compact objects, proposed in quantum gravity models of BHs, may produce similar classical GW waveforms, followed by delayed repeating “echoes.” In a companion paper [1], we have presented different arguments for a universal Boltzmann reflectivity of quantum BH horizons. Here, we investigate the resulting echoes from this prescription. We derive corresponding quasinormal modes (QNMs) for quantum BHs analytically, and show how their initial conditions can be related to the QNMs of classical BHs. Ergoregion instability is suppressed by the imperfect reflectivity. We then compare the analytic and numerical predictions for echoes in real time, verifying their consistency. In particular, we find that the amplitudes of the first $\sim 20$ echoes decay inversely with time, while the subsequent echoes decay exponentially. Finally, we present predictions for the signal-to-noise ratio of echoes for spinning BHs, which should be imminently detectable for massive remnants, subject to the uncertainty in the nonlinear initial conditions of the BH merger.

We study a model of inflation based on $\mathcal{N}=1$ supergravity essentially depending on one effective parameter. Under a field transformation we show that this model turns out to be equivalent to a previously studied supergravity model known to be ruled out with the original choice of the parameter. Such parameter measures the slope of the potential at observable scales. Through a Bayesian parameter estimation, it is shown how this model is compatible with recent cosmic microwave background temperature measurements by Planck 2018 giving rise to a simple, viable, single field model of inflation. The tensor to scalar ratio constraint is found to be $r_{0.002}<0.065$ with negative running. We discuss how observables are invariant under the field transformation which leaves unaltered the slow-roll parameters. As a consequence the use of one presentation of the model or its field-transformed version is purely a matter of convenience.

Theories with a pole in the kinetic term have been used to great effect in studying inflation, owing to their quantum stability and attractor properties. We explore the use of such pole kinetic terms in dark energy theories, finding an interesting link between thawing and freezing models, and the possibility of enhanced plateaus with “superattractorlike” behavior. We assess the observational viability of pole dark energy, showing that simple models can give dark energy equation-of-state evolution with $w(z)<-0.9$ even for potentials that could not normally achieve this easily. The kinetic term pole also offers an interesting perspective with respect to the swampland criteria for such observationally viable dark energy models.

The inclusion of finite-size effects in the gravitational waveform templates allows one not only to constrain the internal structure of compact objects, but to test deviations from general relativity. Here, we address the problem of tidal effects in massless scalar-tensor theories. We introduce the scalar-type tidal Love numbers that relate the time-varying scalar dipole moment to the induced scalar tidal field. We compute the leading-order scalar tidal contribution in the conservative dynamics and for the first time in the wave generation for quasicircular orbits. Importantly, we show that, in a system dominated by dipolar emission, such tidal effects may be detectable by third generation detectors such as the Einstein Telescope.