Fuzzy dark matter with nonzero quartic self-interaction (SFDM) is shown to be a viable model for simultaneously fitting 17 dark-matter-dominated galaxies from the SPARC database with a single $(m,g)$ point in the space of boson masses and self-coupling constants: ${\log }_{10}(m[\mathrm{eV}/c^2])={\log }_{10}(1.98)-22_{-0.6}^{+0.8}$ and ${\log }_{10}(g[{\mathrm{eV}\mathrm{m}}^3/\mathrm{kg}])={\log }_{10}(9.08)-10_{-1.2}^{+0.4}$. This is based on the combination of an appropriately constructed static super-Gaussian profile for the inner galactic core (“soliton”) region, and a Navarro-Frenk-White profile for the surrounding halo region. The explicit identification of a nonzero interaction strength may resolve issues of inconsistent constraints in noninteracting FDM. Our identification of these parameters enables the explicit dynamical reconstruction of potential host halos for such galaxies through numerical solution of the SFDM equations; we outline a proof-of-principle procedure via merger simulations for two galaxies (UGCA444, UGC07866) and show that this yields viable rotation curves over a dynamical period of $\mathcal{O}(1)\mathrm{Gyr}$.

The detection of primordial gravitational waves would offer a direct evidence of inflation and valuable insights into the dynamics of the early Universe. During postinflation reheating period, when the inflaton coherently oscillates at the bottom of its potential, primordial stochastic gravitational waves may be sourced by its perturbative decay into particles of different spins. Assuming the behavior of the potential near the minimum as a polynomial $V(\varphi )\sim {\varphi }^k$, where $k\ge 2$, and treating the inflaton as coherently oscillating classical field, we calculate the decay of inflaton into a pair of spin $3/2$ particles accompanied by graviton emission. We numerically study the reheating dynamics and calculate the stochastic gravitational wave spectra. Our analysis shows that the gravitational wave spectra can offer insights into the microscopic physics during inflation.

We explore the cosmological implications of generalized entropic models within the framework of gravity-thermodynamics (GT) approaches. These models, characterized by three or four additional free parameters, are designed to capture deviations from the standard Bekenstein-Hawking entropy and can reproduce well-known entropic formulations, including Tsallis, Rényi, Sharma-Mittal, Barrow, Kaniadakis, and loop quantum gravity entropies in various analytical limits. We implement the corresponding cosmological models using a fully numerical GT approach to constrain the model parameters and to study the evolution of the dark energy equation of state as a function of the scale factor. Our Bayesian analysis, which incorporates the $\mathrm{Pantheon}+\mathrm{and}$ DESy5 supernovae data alongside the recently released DESI-DR2/DR1 baryon acoustic oscillation (BAO) measurements, shows that the data favor the standard Bekenstein-Hawking entropy, leading to a $\mathrm{\Lambda }\mathrm{CDM}$-like late-time behavior. In this context, the three-parameter (${\mathcal{S}}_3$) entropic model appears to be sufficient to capture the observed dark energy phenomenology. Furthermore, a direct comparison of the Bayesian evidence indicates that the three-parameter model is preferred over the four-parameter (${\mathcal{S}}_4$) variant by a factor of $\mathrm{\Delta }\log \mathcal{B}\sim -6$, while the GT approach as a whole is significantly disfavored relative to the $\mathrm{\Lambda }\mathrm{CDM}$ model with at least $\mathrm{\Delta }\log \mathcal{B}\sim -8$ (${\mathcal{S}}_3$) to $\mathrm{\Delta }\log \mathcal{B}\sim -13$ (${\mathcal{S}}_4$), when using the DESy5 and DESI-DR2 datasets.

Primordial black holes (PBHs) may constitute a considerable fraction of dark matter. In this work we use the recent observations by the LIGO-Virgo-KAGRA (LVK) collaborations to set direct limits on stellar-mass range PBHs. We evaluate the merger rates of PBH binaries by accounting for the binaries formed by two-body captures inside dark matter halos and by studying the evolution of PBH binaries inside such halos through binary-single interactions. Those type of interactions contribute to what is a minimum of PBH merger rates at low redshifts detectable by LVK. Thus, they allow us to derive what is the most conservative upper limits on the presence of merging PBH binaries in the gravitational-wave observations. We study both the case where PBHs have a monochromatic mass distribution and the case where that distribution is described by a log-normal function. To derive limits on PBHs, we simulate binaries with masses following the relevant mass distributions and merger rates as a function of redshift, up to $z\sim 0.8$, relevant for the current LVK observations. In those simulations we also take into account that the LVK observatories measure the detected black hole binaries’ masses with a finite resolution. In comparing to the LVK observations, we combine the simulated PBH binaries with the binaries following a power-law mass- and redshift distribution. The latter binaries dominate the observed population of LVK detections. Our derived limits on the mass fraction of dark matter composed of PBHs are in the range of ${10}^{-4}$ to $2\times {10}^{-2}$, depending on the exact assumptions relating to the PBH binaries properties. For reasonable assumptions on those PBH binaries’ properties before their evolution inside dark matter halos, we get that fraction to be in the range of ${10}^{-3}-{10}^{-2}$, for PBH masses of $5-80M_{\odot }$. Our work provides some of the most competitive limits in the mass range of $5-50M_{\odot }$.

We investigate the detectability of post-Newtonian higher harmonics from Galactic double white dwarfs in the centihertz band ($\sim 0.01\mathrm{Hz}$). Using a synthetic population, we show that, unlike the quadrupole mode, higher harmonics remain undetectable with the Laser Interferometer Space Antenna (LISA) except for rare nearby systems. In contrast, planned mid-band (decihertz) observatories such as DECIGO and BBO will be able to detect the third harmonic for about 10% of inspiral binaries above $\sim 5\mathrm{mHz}$, enabling statistical constraints on mass ratios. These results highlight the successive roles of LISA and future decihertz missions in establishing a coherent strategy for space-based gravitational wave astronomy.

We study bottomonium suppression in $p+\mathrm{Pb}$ relative to $p+p$ collisions at center-of-mass energies of $\sqrt{s_{NN}}=5.02$ and 8.16 TeV. Specifically, we combine cold nuclear matter effects (nuclear modifications of the parton densities, energy loss, and momentum broadening) with those from hot nuclear matter (suppression and regeneration) by implementing the formation of a quark-gluon plasma in hydrodynamic simulations. Bottomonium transport in the quark-gluon plasma is evaluated semiclassically, employing two different reaction rates. The first includes quasifree inelastic scattering and gluodissociation employing a perturbative coupling to the medium. The second is based on in-medium $T$-matrix calculations where the input potential is constrained by lattice quantum chromodynamics to extract the bottomonium masses and dissociation rates. These semiclassical results are compared to previous calculations in an open quantum system approach and to the experimental data. Predictions for ${\chi }_b$ suppression at $\sqrt{s_{NN}}=8.16\mathrm{TeV}$ are also presented.

We develop a worldline-instanton approach for calculating the momentum spectrum of particles produced by gravitational fields that depend on both space and time. The instantons are open. The middle part is complex and describes the formation region, while the ends describe the trajectories of asymptotic particles.

We investigate the formation of primordial black holes (PBHs) induced by a first-order electroweak phase transition in a realistic renormalizable framework, the complex singlet extension of the Standard Model. We perform a quantitative analysis of the PBH abundance and identify parameter regions consistent with current microlensing constraints. Furthermore, we show that the same parameter space predicts observable stochastic gravitational waves within the sensitivities of future space-based detectors, as well as a sizable deviation in the Higgs triple coupling that can be probed at future lepton colliders. Our results highlight a comprehensive multimessenger framework in which PBHs, gravitational waves, and collider observations can jointly test the dynamics of a strongly first-order electroweak phase transition in the early Universe.

The dark matter may consist of multiple species that interact differently. We show that a species that is cosmologically subdominant but highly self-collisional can pile up and become dominant in deep gravitational wells, such as those of white dwarfs and neutron stars.

If axions simultaneously have the scalar couplings to the nucleons and pseudoscalar couplings to the electrons, it may mediate a $\mathcal{P}$, $\mathcal{T}$-violating interaction between the electronic shell and nuclei in the molecules. The polyatomic molecule RaOH, which is considered a promising platform for the $\mathcal{P}$, $\mathcal{T}$-violation searches, is studied for its sensitivity to such interactions. Because of the long-range nature (on molecular scales) of the axion-mediated interaction, it is important whether the molecular parameter is sensitive to the vibration of the molecule. Our results imply that the impact of the vibrations on the axion-mediated electron-nucleon interaction in the molecule is similar to the impact on the short-range electron-nucleon scalar-pseudoscalar interaction studied earlier.

Although the axion is the most compelling solution to the strong $CP$ problem, the ad hoc introduced global Peccei-Quinn symmetry suffers from a severe fine-tuning problem known as the quality problem. In this letter, we show that the discrete gauge symmetry ${\mathbb{Z}}_4\times {\mathbb{Z}}_3$ motivated from the internal structure of the standard model can naturally predict a high-quality axion, leading to a distinct and testable parameter space. Remarkably, this minimal framework simultaneously accounts for neutrino masses, baryon asymmetry, and dark matter.

Light polarization plays a crucial role in optical-cavity experiments; however, mirror birefringence presents a significant challenge that must be addressed carefully. In this study, a rigorous, nonperturbative framework is developed to quantify birefringence effects by incorporating variations in reflectance and polarization misalignment. We analyze the impact of this framework on the sensitivity of axionlike particle (ALP) dark matter searches. The results show that both birefringence and misalignment contribute to sensitivity degradation in the low-mass regime; however, the adverse effects of misalignment can be mitigated by selecting a postselection angle greater than the misalignment angle. Furthermore, birefringence produces an additional resonance peak in the high-mass region, which remains largely unaffected by misalignment and postselection variations. This rigorous framework underscores the importance of considering birefringence in high-precision optical-cavity experiments for ALP detection.

Neutrinoless double-beta ($0\nu \beta \beta$) decays provide an excellent probe for determining whether neutrinos are Dirac or Majorana fermions. The short-range matrix elements associated with the ${\pi }^{-}\to {\pi }^{+}ee$ process contribute at leading order in the $0\nu \beta \beta$ decay channel $nn\to ppee$ through pion exchange between nucleons. However, current lattice calculations show notable discrepancies in predicting these short-range contributions. To address this issue, we perform a lattice QCD calculation of the ${\pi }^{-}\to {\pi }^{+}ee$ matrix elements using domain wall fermion ensembles at the physical pion mass generated by the RBC/UKQCD Collaboration. To mitigate contamination from around-the-world effects, we develop a new method to reconstruct and subtract them directly from lattice data. We then perform nonperturbative renormalization in the regularization-independent symmetric momentum-subtraction scheme (RI/SMOM), using the $({\gamma }_{\mu },{\gamma }_{\mu })$ and $(\cancel{q},\cancel{q})$ projectors. Compared with previous studies, this work reduces the uncertainties in the matrix elements and provides an independent cross-check that helps to reconcile the discrepancies among previous lattice calculations.

The long-distance contribution of QED corrections to the hadronic vacuum polarization is particularly challenging to compute in lattice $\mathrm{QCD}+\mathrm{QED}$. Currently, it is one of the limiting factors toward matching the precision of the recent result by the Fermilab E989 experiment for the muon $g-2$. In this work, we present a method for obtaining high-precision results for this contribution by reconstructing exclusive finite-volume state contributions. We find relations between the pion-photon contributions of individual diagrams and demonstrate the reconstruction method with lattice $\mathrm{QCD}+\mathrm{QED}$ data at a single lattice spacing of $a^{-1}\approx 1.73\mathrm{GeV}$ and $m_{\pi }\approx 275\mathrm{MeV}$.

The calculation of inclusive processes that involve the production of many particles is a challenge for lattice quantum chromodynamics (QCD), a Euclidean-space method that is far removed from real-time, multiparticle production. A new approach to this problem based on Nevanlinna-Pick interpolation has been proposed by Bergamaschi et al. Here we extend their method by exploring the propagation of the statistical and systematic errors that accompany a lattice QCD calculation through this interpolation process. A simplified example of a multiparticle spectral function is studied with a focus on the possible applications of these methods to the calculation of inclusive heavy-particle decays.

We present a compact form of the massive $1\to 3$ tree-level QCD splitting functions and discuss a decomposition of the results in terms of lower-order expressions, scalar dipole antenna functions and pure higher-order remainders. The two-gluon radiator functions introduced in this context are novel and generalize expressions obtained from the double-soft approximation. Our results are obtained without reference to soft or quasicollinear limits.

The simplest atomic nucleus, the deuteron, provides key insights into the strong nuclear interactions among quarks and gluons that shape the visible Universe. We present the first attempt to calculate the internal structure of the deuteron by incorporating hidden-color degrees of freedom, modeling it as an effective mixture of singlet-singlet and octet-octet color clusters beyond the traditional proton-neutron picture. By employing the separation of variables for the light-front two-cluster bound-state equation, we explore how these hidden color correlations shape both its spin and electromagnetic structure. We incorporate the transverse and longitudinal dynamics by two Schrödinger-like equations, namely, the light-front holography and the ’t Hooft equation, respectively. Our results for the electromagnetic form factors and structure functions, including tensor-polarized function, align well with experimental data, offering insights into the partonic structure of the deuteron. Its tensor property could pave the way for a new era in spin physics, guiding future experimental investigations.

We investigate the process in which deeply virtual Compton scattering (DVCS) excites a baryon resonance. In particular, we assess, in DVCS leading to the Roper resonance, the relative importance of a “background” process in which a pion is first emitted by the nucleon, which then undergoes a DVCS event. Our numerical results, using realistic DVCS kinematics, indicate that there can be measurable interference effects. They suggest that this process could substantially modify the experimentally observed cross sections at CLAS12-like kinematics, motivating their inclusion in precision analyses of DVCS experiments. We further find that in spite of this background, the transition to a Roper-like state through DVCS does contribute significantly to the $e^{-}N\to e^{-}\gamma N\pi$ cross section in some kinematic regions. This suggests that the creation of nucleon resonances via DVCS is a useful method for extracting information about the nucleon transition GPDs and the internal structure of the excited states.

A potential quark model is used to search for a $P_{c\overline{c}s}^0=(c\overline{c}uds{)}^0$, $J^P=1/2^{-}$ pentaquark state that has recently been observed experimentally by LHCb Collaboration at 4338.2 MeV, with a width of 7.0 MeV and high statistical significance $>15\sigma$. Our model Hamiltonian reproduces the masses of the low-lying charmed and strange hadrons. We use the Gaussian expansion method to solve the five-body Schrödinger equation. Employing the real scaling method, including the relevant meson-baryon thresholds explicitly, sharp resonances are distinguished from the meson-baryon scattering states. We incorporate new color states of the color-octet meson and baryon configurations as well as the color-singlet configurations for the five-quark states. We find no $J^P=1/2^{-}$ resonance close to the observed state, and also none in the $J^P=3/2^{-}$ state. This increases the likelihood that $P_{c\overline{c}s}^0$ is a ${\mathrm{\Xi }}_c\overline{D}$ hadronic molecule rather than a compact state.

We propose two medium-baseline, kiloton-scale neutrino experiments to study neutrinos from LHC proton-proton collisions: the Surface-based Integrated Neutrino Experiment (SINE), a surface-based scintillator panel detector observing muon neutrinos from the compact muon solenoid interaction point, and the UNDerwater Integrated Neutrino Experiment (UNDINE), a water Cherenkov detector submerged in lake Geneva observing all-flavor neutrinos from LHCb. Using a Monte Carlo simulation, we estimate millions of neutrino interactions during the high-luminosity LHC era. We show that these datasets can constrain neutrino cross sections, charm production in $pp$ collisions, strangeness enhancement as a solution to the cosmic-ray muon puzzle, and heavy neutral leptons. SINE and UNDINE thus offer a cost-effective medium-baseline complement to the proposed short-baseline forward physics facility.