We consider gauge theories of non-Abelian $finite$ groups, and discuss the $1+1$ dimensional lattice gauge theory of the permutation group $S_N$ as an illustrative example. The partition function at finite $N$ can be written explicitly in a compact form using properties of $S_N$ conjugacy classes. A natural large-$N$ limit exists with a new ’t Hooft coupling, $\lambda =g^2\log N$. We identify a Gross-Witten-Wadia-like phase transition at infinite $N$, at $\lambda =2$. It is first order. An analog of the string tension can be computed from the Wilson loop expectation value, and it jumps from zero to a finite value. We view this as a type of large-$N$ (de)confinement transition. Our holographic motivations for considering such theories are briefly discussed.

We study the Jeans mass-radius relation of Bose-Einstein condensate dark matter in Newtonian gravity. We show at a general level that it is similar to the core mass-radius relation of Bose-Einstein condensate dark matter halos [, Phys. Rev. D 84, 043531 (2011)]. Bosons with a repulsive self-interaction generically evolve from the Thomas-Fermi regime to the noninteracting regime as the Universe expands. In the Thomas-Fermi regime, the Jeans radius remains approximately constant while the Jeans mass decreases. In the noninteracting regime, the Jeans radius increases while the Jeans mass decreases. Bosons with an attractive self-interaction generically evolve from the nongravitational regime to the noninteracting regime as the Universe expands. In the nongravitational regime, the Jeans radius and the Jeans mass increase. In the noninteracting regime, the Jeans radius increases while the Jeans mass decreases. The transition occurs at a maximum Jeans mass which is similar to the maximum core mass of Bose-Einstein condensate dark matter halos with an attractive self-interaction. We use the core mass-radius relation of dark matter halos and the observational evidence of a “minimum halo” (with typical radius $R\sim 1\mathrm{kpc}$ and typical mass $M\sim {10}^8{M}_{\odot }$) to constrain the mass $m$ and the scattering length $a_s$ of the dark matter particle. For noninteracting bosons, $m$ is of the order of $2.92\times {10}^{-22}\mathrm{eV}/c^2$. The mass of bosons with an attractive self-interaction can be only slightly smaller ($2.19\times {10}^{-22}\mathrm{eV}/c^2<m<2.92\times {10}^{-22}\mathrm{eV}/c^2$ and $-1.11\times {10}^{-62}\mathrm{fm}\le a_s\le 0$); otherwise, the minimum halo would be unstable. Constraints from particle physics and cosmology imply $m=2.92\times {10}^{-22}\mathrm{eV}/c^2$ and $a_s=-3.18\times {10}^{-68}\mathrm{fm}$ for ultralight axions, and it is then found that attractive self-interactions can be neglected in both the linear and the nonlinear regimes of structure formation. The mass of bosons with a repulsive self-interaction can be larger by 18 orders of magnitude ($2.92\times {10}^{-22}\mathrm{eV}/c^2<m<1.10\times {10}^{-3}\mathrm{eV}/c^2$ and $0\le a_s\le 4.41\times {10}^{-6}\mathrm{fm}$). The maximum allowed mass ($m=1.10\times {10}^{-3}\mathrm{eV}/c^2$ and $a_s=4.41\times {10}^{-6}\mathrm{fm}$) is determined by the Bullet Cluster constraint while the transition between the noninteracting limit and the Thomas-Fermi limit corresponds to $m=2.92\times {10}^{-22}\mathrm{eV}/c^2$ and $a_s=8.13\times {10}^{-62}\mathrm{fm}$. For each of these models, we calculate the Jeans length and the Jeans mass at the epoch of radiation-matter equality and at the present epoch.

We present a joint likelihood analysis of the real-space power spectrum and bispectrum measured from a variety of halo and galaxy mock catalogs. A novel aspect of this work is the inclusion of nonlinear triangle configurations for the bispectrum, made possible by a complete next-to-leading order (“one-loop”) description of galaxy bias, as is already common practice for the power spectrum. Based on the goodness of fit and the unbiasedness of the parameter posteriors, we accomplish a stringent validation of this model compared to the leading order (“tree-level”) bispectrum. Using measurement uncertainties that correspond to an effective survey volume of $6(\mathrm{Gpc}/h{)}^3$, we determine that the one-loop corrections roughly double the applicable range of scales, from $\sim 0.17h/\mathrm{Mpc}$ (tree level) to $\sim 0.3h/\mathrm{Mpc}$. This converts into a 1.5–2x improvement on constraints of the linear bias parameter at fixed cosmology, and a 1.5–2.4x shrinkage of uncertainties on the amplitude of fluctuations $A_s$, which clearly demonstrates the benefit of extracting information from nonlinear scales despite having to marginalize over a larger number of bias parameters. Besides, our precise measurements of galaxy bias parameters up to fourth order allow for thorough comparisons to coevolution relations, showing excellent agreement for all contributions generated by the nonlocal action of gravity. Using these relations in the likelihood analysis does not compromise the model validity and is crucial for obtaining the quoted improvements on $A_s$. We also analyzed the impact of higher-derivative and scale-dependent stochastic terms, finding that for a subset of our tracers the former can boost the performance of the tree-level model with constraints on $A_s$ that are only slightly degraded compared to the one-loop model.

The standard cooling scenario in the presence of nucleon superfluidity fits rather well to the observation of the neutron stars. It implies that the stellar cooling arguments could place a stringent constraint on the properties of novel particles. We study in particular the cooling rate induced by dark gauge bosons for very young neutron stars: remnants of Cassiopeia A and SN1987A. The cooling is dominantly contributed either by the nucleon pair breaking and formation in the core or by the electron bremsstrahlung in the crust, depending on the age of the stars and the form of the couplings. We compute how much the cooling curve of the young neutron stars could be modified by the extra dark gauge boson emission and obtain the bound for the dark gauge boson when its mass is lower than $\mathcal{O}(0.1)\mathrm{MeV}$; for the dark photon, we find the mixing parameter times its mass $ϵm_{{\gamma }^{\prime }}<1.5\times 10^{-8}\mathrm{MeV}$ and for the $\mathrm{U}(1{)}_{B-L}$ gauge boson its coupling to nucleons and electrons $e^{\prime }<5\times 10^{-13}$. We also discuss the possibility that the rapid cooling of Cas A might provide a hint for the existence of the $\mathrm{U}(1{)}_{B-L}$ gauge boson of mass around eV and its coupling $e^{\prime }\sim 10^{-13}$.

Fast radio bursts (FRBs) are mysterious astronomical radio transients with extremely short intrinsic duration. Until now, the physical origins of them still remain elusive, especially for the nonrepeating FRBs. Strongly inspired by recent progress on possible evidence of Earth-mass primordial black holes, we revisit the model of Earth-mass primordial black holes mergers as sources for nonrepeating FRBs. Under the null hypothesis that the observed nonrepeating FRBs originate from the mergers of Earth-mass primordial black holes, we analyzed four independent samples of nonrepeating FRBs to study the model parameters, i.e., the typical charge value $q_{\mathrm{c}}$ and the power index $\alpha$ of the charge distribution function of the primordial black hole population $\varphi (q)\propto (q/q_{\mathrm{c}}{)}^{-\alpha }$, which describe how the charge was distributed in the population. $q$ is the charge of the hole in the unit of $\sqrt{G}M$, where $M$ is the mass of the hole. It turns out that this model can explain the observed data well. Assuming the monochromatic mass spectrum for primordial black holes, we get the average value of typical charge ${\overline{q}}_{\mathrm{c}}/{10}^{-5}=1.59_{-0.18}^{+0.08}$ and the power index $\overline{\alpha }=4.53_{-0.14}^{+0.21}$ by combining the fitting results given by four nonrepeating FRB samples. The event rate of the nonrepeating FRBs can be explained in the context of this model if the abundance of the primordial black hole populations with charge $q\gtrsim {10}^{-6}$ is larger than ${10}^{-5}$, which is far below the upper limit given by current observations for the abundance of Earth-mass primordial black holes. In the future, simultaneous detection of FRBs and high frequency gravitational waves produced by mergers of Earth-mass primordial black holes may directly confirm or deny this model.

We show, by numerical calculations, that there exist three types of stationary and spherically symmetric nontopological soliton (NTS) solutions (NTS balls) with large sizes in the coupled system consisting of a complex matter scalar field, a U(1) gauge field, and a complex Higgs scalar field that causes spontaneously symmetry breaking. Under the assumption of symmetries, the coupled system reduces to a dynamical system with 3 degrees of freedom governed by an effective action. The effective potential in the action has stationary points. The NTS balls with large sizes are described by bounce solutions that start off with an initial stationary point and traverse to the final stationary point, the vacuum stationary point. According to the choice of the initial stationary point, there appear three types of NTS balls: dust balls, shell balls, and potential balls with respect to their internal structures.

As is well established, several gauge theories admit vortices whose mean lifetime is very large. In some cases, this stability is a consequence of the topology of the symmetry group of the underlying theory. The main focus of the present work is, given a putative vortex, to determine if it is non-Abelian or not by analysis of its physical effects. The example considered here is the simplest one, namely, a $SU(2)$ gauge model whose internal orientational space is described by $S^2$. Axion and gravitational emission are mainly considered. It is found that the non-Abelian property is basically reflected in a deviation of gravitational loop factor ${\gamma }_l$ found in [T. Vachaspati and A. Vilenkin, Phys. Rev. D 31, 3052 (1985), C. Burden, Phys. Lett. 164B, 277 (1985)]. The axion emission instead, is not very sensitive to non-Abelianity, at least for this simple model. Another important discrepancy is that no point of the vortex reaches the speed of light when orientational modes are excited. In addition, the total power corresponding to each of these channels is compared, thus adapting the results of [R. Davis, Phys. Rev. D 32, 3172 (1985), M. Srednicki and S. Theisen, Phys. Lett. B 189, 397 (1987), and M. Peloso and L. Sorbo, Nucl. Phys. B649, 88 (2003)] to the non-Abelian context. The excitations considered here are simple generalizations of rotating or spike string ansatz known in the literature [S. Gubser, I. Klebanov, and A. Polyakov, Nucl. Phys. B636, 99 (2002), J. Russo, J. High Energy Phys. 06 (2002) 038, S. Frolov and A. Tseytlin, J. High Energy Phys. 06 (2002) 007, and R. Izhizeki and M. Kruczenski, Phys. Rev. D 76, 126006 (2007)]. It is suggested however, that for certain type of semilocal strings whose internal moduli space is noncompact, deviations due to non-Abelianity may be more pronounced.

We probe the inner structure of the meson $D_{s0}^{*}(2317)$ through the decays of $B_{(s)}$ to two charmed mesons within the pQCD approach. Assuming $D_{s0}^{*}(2317)$ as a scalar meson with $\overline{c}s$ structure, we find that the predictions for the branching ratios of the decays $B^{+}\to D_{s0}^{*+}(2317){\overline{D}}^{(*)0}$, $B^0\to D_{s0}^{*+}(2317)D^{(*)-}$ can explain data within errors. The branching ratios for the decays $B_s\to D_{s0}^{*+}(2317)D_s^{(*)+}$ are estimated to reach up to ${10}^{-3}$ order, which can be observed by the present LHCb and SuperKEKB experiments. In this work, the decay constant of the meson $D_{s0}^{*}(2317)$ is an input parameter. Unfortunately, its value has been studied by many references but with large uncertainties. Our calculation shows that a smaller decay constant of the meson $D_{s0}^{*}(2317)$ is supported by compared with the present data, say 55–70 MeV. We also calculate the ratios $R_1=\frac{\mathrm{Br}(B^{+}\to D_{s0}^{*+}(2317){\overline{D}}^0)}{\mathrm{Br}(B^{+}\to D_{s0}^{*+}(2317){\overline{D}}^{*0})})$ and $R_2=\frac{\mathrm{Br}(B^0\to D_{s0}^{*+}(2317)D^{-})}{\mathrm{Br}(B^0\to D_{s0}^{*+}(2317)D^{*-})}$, which are valuable to determine the inner structure of $D_{s0}^{*}(2317)$ by compared with the experimental results. Our predictions for the ratios $R_{1,2}$ are consistent with the present data within errors. We expect that these two ratios can be well measured by the future experiments through improving the measurement accuracy for the decays $B^{+}\to D_{s0}^{*+}(2317){\overline{D}}^{*0}$ and $B^0\to D_{s0}^{*+}(2317)D^{*-}$.

We investigate the electroweak phase transition in the real-singlet extension of the Standard Model at two-loop level, building upon existing one-loop studies. We calculate the effective potential in the high-temperature approximation and detail the required resummations at two-loop order. In typical strong-transition scenarios, we find deviations of order 20%–50% from one-loop results in transition strength and critical temperature for both one- and two-step phase transitions. For extremely strong transitions, the discrepancy with one-loop predictions is even larger, presumably due to sizable scalar couplings in the tree-level potential. Along the way, we obtain a dimensionally reduced effective theory applicable for nonperturbative lattice studies of the model.

The masses of ground and excited states of ${\mathrm{\Omega }}_c^0$, ${\mathrm{\Omega }}_{cc}^{+}$, and ${\mathrm{\Omega }}_{ccc}^{*++}$ baryons are calculated within the framework of Regge phenomenology. Here our attempt is to assign a possible spin parity to these obtained masses. Our calculated masses in the $(J,M^2)$ plane with both natural ($J^P=1/2^{+},3/2^{-},5/2^{+},\dots$) and unnatural ($J^P=3/2^{+},5/2^{-},7/2^{+},\dots$) spin parities are in agreement with the experimental observations where available and reasonably close to other theoretical predictions. Further, we fix the slope and intercept of each Regge line in the $(n,M^2)$ plane and estimate the masses of higher excited states of these baryons. The obtained mass relations and the mass value predictions could provide useful information in future experimental searches and the spin-parity assignment of these states.

In this work, we carry out the study of heavy flavor pentaquarks with four heavy quarks, which have typical $QQQQ\overline{q}$ configuration. Within the chromomagnetic interaction model, the mass spectrum of these discussed $QQQQ\overline{q}$ pentaquarks is given. In addition to the mass spectrum analysis, we also illustrate their two-body strong decay behavior by estimating some ratios of decay channels. By these efforts, we suggest that a future experiment should pay attention to this kind of pentaquark.

Recently it was shown that classical electromagnetism admits new asymptotic conservation laws [, New asymptotic conservation laws for electromagnetism, J. High Energy Phys. 02 (2021) 082.]. In this paper we derive the analog of the first of these asymptotic conservation laws upon the imposing Feynman boundary condition on the radiative field. We also show that the Feynman solution at $\mathcal{O}(e^3)$ contains purely imaginary modes falling off as $\{\frac{\log u}{u^{n}r},n\ge 0\}$ which are absent in the retarded solution. The $\log u$ mode has also appeared [ and , Loop corrected soft photon theorem as a Ward identity, J. High Energy Phys. 10 (2019) 287; , Ward identity for loop level soft photon theorem for massless QED coupled to gravity, J. High Energy Phys. 10 (2020) 110.] and violates the Ashtekar-Struebel falloffs for the radiative field [ and , Symplectic geometry of radiative modes and conserved quantities at null infinity, Proc. R. Soc. A 376, 585 (1981).]. We expect that new $\frac{(\log u{)}^m}{u^{m}r}$ modes would appear in the Feynman solution at order $\mathcal{O}(e^{2m+1})$. Thus, all the other modes are expected to preserve the Ashtekar-Struebel falloffs.

We study the gravitational field sourced by localized scalar fields (lumps) in higher-derivative theories of gravity. By working in a static and spherically symmetric configuration, we find the linearized spacetime metrics generated by scalar lumps for several Lagrangians: the vanishing potential, i.e., free massive scalar field, a polynomial potential, and the tachyon potential in open string field theory. We perform the analysis for different theories of gravity: Einstein’s general relativity, four-derivative gravity, and ghost-free nonlocal gravity. We discuss the limit of validity of our analysis and comment on possible future applications in the context of astrophysical compact objects.

Bayesian inference is used to extract unknown parameters from gravitational-wave signals. Detector noise is typically modeled as stationary, although data from the LIGO and Virgo detectors is not stationary. We demonstrate that the posterior of estimated waveform parameters is no longer valid under the assumption of stationarity. We show that while the posterior is unbiased, the errors will be under- or overestimated compared to the true posterior. A formalism was developed to measure the effect of the mismodeling, and found the effect of any form of nonstationarity has an effect on the results, but are not significant in certain circumstances. We demonstrate the effect of short-duration Gaussian noise bursts and persistent oscillatory modulation of the noise on binary-black-hole-like signals. In the case of short signals, nonstationarity in the data does not have a large effect on the parameter estimation, but the errors from nonstationary data containing signals lasting tens of seconds or longer will be several times worse than if the noise was stationary. Accounting for this limiting factor in parameter sensitivity could be very important for achieving accurate astronomical results. This methodology for handling the nonstationarity will also be invaluable for analysis of waveforms that last minutes or longer, such as those we expect to see with the Einstein Telescope.

We use observations of gas-rich dwarf galaxies to derive constraints on dark matter scattering with ordinary matter. We require that heating/cooling due to dark matter (DM) interacting with gas in the Leo T dwarf galaxy not exceed the ultralow radiative cooling rate of the gas. This enables us to set (i) stronger bounds than all the previous literature on ultralight hidden photon DM for nearly all of the mass range ${10}^{-23}\lesssim m_{\mathrm{DM}}\lesssim {10}^{-10}\mathrm{eV}$, (ii) limits on sub-GeV millicharged DM which add to the constraints on the recent EDGES 21 cm absorption anomaly, and (iii) constraints on DM-baryon interactions directly at low relative velocities $v_{\mathrm{rel}}\sim 17\mathrm{km}/\mathrm{s}$. Our study opens a new direction in using observations of gas-rich dwarf galaxies from previous, current, and upcoming optical and 21 cm surveys to probe physics beyond the standard model.

The total cross section of the process $e^{+}{e}^{-}\to p\overline{p}$ is calculated within the energy range close to the mass of $\psi (3770)$ charmonium state. It was shown that the main contribution to this cross section comes from three gluon mechanism which is also responsible of the large phase with respect to the Born amplitude. This phase provides the characteristic dip behavior of the cross section in contrast to the usual Breit-Wigner peak shape. Okubo–Zweig–Iizuka-allowed mechanism with $D$-mesons in the intermediate state was also estimated and gives relatively small contribution to the cross section and to the phase.

We present the results of an explicit numerical computation of a novel instanton in Georgi-Glashow SU(2) theory. The instanton is physically relevant as a mediator of Schwinger production of ’t Hooft–Polyakov magnetic monopoles from strong magnetic fields. In weak fields, the pair production rate has previously been computed using the worldline approximation, which breaks down in strong fields due to the effects of finite monopole size. Using lattice field theory we have overcome this limit, including finite monopole size effects to all orders. We demonstrate that a full consideration of the internal monopole structure results in an enhancement to the pair production rate, and confirm earlier results that monopole production becomes classical at the Ambjørn-Olesen critical field strength.

We study the quark-gluon vertex in the limit of vanishing gluon momentum using lattice QCD with two flavors of $\mathcal{O}(a)$ improved Wilson fermions, for several lattice spacings and quark masses. We find that all three form factors in this kinematics have a significant infrared strength and that both the leading form factor ${\lambda }_1$, multiplying the tree-level vertex structure, and the scalar, chiral symmetry breaking form factor ${\lambda }_3$ are significantly enhanced in the infrared compared to the quenched ($N_f=0$) case. These enhancements are orders of magnitude larger than predicted by one-loop perturbation theory. We find only a weak dependence on the lattice spacing and quark mass.

The line shapes of specific production experiments of the exotic state such as $X(3872)$ with $J^{PC}=1^{++}$ quantum numbers involving triangle singularities have been found to become highly sensitive to the binding energy of weakly bound states, thus offering in principle the opportunity of benchmark determinations. We critically analyze recent proposals to extract accurately and precisely the $X(3872)$ mass, which overlook an important physical effect by regarding their corresponding production line shapes as a sharp mass distribution and, thus, neglecting the influence of initial nearby continuum states in the $1^{++}$ channel. The inclusion of these states implies an effective cancellation mechanism which operates at the current and finite experimental resolution of the detectors so that one cannot distinguish between the $1^{++}$ bound state and nearby $D{\overline{D}}^{*}$ continuum states with the same quantum numbers. In particular, we show that the line shape for resolutions above 1 MeV becomes rather insensitive to the binding energy unless high statistics is considered. The very existence of the observed bumps is a mere consequence of short distance correlated $\overline{D}{D}^{*}$ pairs, bound or unbound. The cancellation also provides a natural explanation for a recent study reporting missing but unknown decay channels in an absolute branching ratio global analysis of the $X(3872)$.

Modern neutrino detectors, particularly the large liquid argon time projection chambers (LAr TPCs) at SBN and DUNE, provide an unprecedented amount of information about GeV-scale interactions. By taking advantage of the excellent spatial and calorimetric resolution as well as the low tracking thresholds provided by LAr TPCs, we present a novel method of estimating the neutrino energy in neutral current interactions. This method has potential implications for the search for a sterile neutrino; it allows for the potential observation of spectral distortions due to sterile neutrino-induced oscillations in the neutral current neutrino energy spectrum. As an example, we use this method to perform an analysis of the statistics-only sensitivity to sterile neutrinos in the neutral current channel at SBN under a $3+1$ model.