Papers

We study the entanglement generated by Newtonian self-gravity in a two-particle system of mixed neutrinos and quantify it by means of the concurrence. Starting from the gravitational coupling between the mass operators, we show that the two-particle Hamiltonian splits into local single-particle terms and an effective Ising interaction in the mass basis, the latter being solely responsible for the generation of correlations. For initially separable flavor states the concurrence is obtained in closed analytic form: it oscillates between zero and a maximum fixed by the mixing angle alone, while the gravitational coupling sets the recurrence time. We further establish a one-to-one correspondence between the concurrence and the reduced-state purity previously derived for this model, thus providing an independent quantum-information description of the same gravitationally induced correlations. Finally, we show that the concurrence does not depend on the Majorana phase, so that Dirac and Majorana parametrizations yield identical entanglement dynamics. These results isolate the genuinely entangling sector of the gravitational evolution and provide a compact analytic characterization of gravity-induced quantum correlations in mixed neutrino systems.

Recent measurements from DESI baryon acoustic oscillations (BAO) have reported a moderate preference for dynamical dark energy, challenging the standard $\Lambda$CDM paradigm. Nonetheless, such a trend could reflect a tension between the shape and the offset of the Hubble diagrams predicted by current BAO and Type Ia supernovae (SN) data, which may underpin a possible breakdown of the cosmic distance duality relation (CDDR) linking luminosity distances $D_{\rm L}$ and angular-diameter distances $D_{\rm A}$. We explore this possibility by parametrizing deviations from this relation as $\eta(z) \equiv D_{\rm L} / [{(1+z)}^2 D_{\rm A}] = \alpha{(1+z)}^\varepsilon$, and investigate how the preference for a Chevallier-Polarski-Linder (CPL) dynamical dark energy is modified once $\varepsilon \!\neq\! 0$ is allowed. Using DESI DR2 and uncalibrated SN data (Pantheon$+$, DES-Dovekie, Union3, and Union3.1), we find that allowing $\varepsilon$ to vary freely in both $\Lambda$CDM and CPL reduces the CPL preference with respect to $\Lambda$CDM by a larger amount than the addition of spatial curvature $\Omega_k$; only Union3.1 exhibits comparable reductions. We also find that the preference reduction is robust to alternative $\eta(z)$ parametrizations, and that the $\eta(z)$ constraints remain stable under the removal of BAO tracers or low-redshift cutoffs for Pantheon$+$, whereas the DES-Dovekie preference largely disappears once $z < 0.1$ SN are removed. In a separate calibrated analysis, illustrative Planck sound-horizon and SH0ES absolute-magnitude priors give $\alpha \simeq 0.942 \pm 0.014$, quantifying the normalization mismatch under those assumptions. We also map the CDDR violation onto photon-loss and varying-$G$ scenarios, concluding that the cosmological constraints are much weaker than existing constraints on these physical mechanisms.

The single production of first-generation $\mathrm{SU}(2)_L$ doublet vector-like leptons (VLLs) at the Compact Linear Collider (CLIC) with $\sqrt{s}=3~\mathrm{TeV}$ is studied. The neutral and charged VLL states are investigated through $e^+e^-\rightarrow\nu_e\bar N+\bar\nu_eN$ and $e^+e^-\rightarrow e^\pm E^\mp$, respectively. The neutral VLL is searched for in the $N\rightarrow W^\mp e^\pm$ channel with $W^\pm\rightarrow jj$, leading to the $e^\pm+2j+\slashed{E}_T$ final state. The charged VLL is explored through $E^\pm\rightarrow e^\pm h$ ($h\rightarrow b\bar b$) and $E^\pm\rightarrow e^\pm Z$ ($Z\rightarrow q\bar q$), yielding the $e^+e^-+2b$ and $e^+e^-+2j$ signatures. Signal and background simulations include initial-state radiation, beamstrahlung, and detector effects. Cut-based analyses are performed for integrated luminosities of $1$, $3$, and $5~\mathrm{ab}^{-1}$ to obtain the exclusion and discovery sensitivities in the VLL mass–mixing parameter space. The neutral-VLL channel gives the best sensitivity. At $1~\mathrm{ab}^{-1}$, the $2\sigma$ exclusion reaches $\varepsilon\simeq0.013$ at $M_N=1.3~\mathrm{TeV}$ and $\varepsilon\simeq0.065$ at $M_N=2.9~\mathrm{TeV}$, while the $5\sigma$ discovery reach corresponds to $\varepsilon\simeq0.02$–$0.10$. At $5~\mathrm{ab}^{-1}$, the charged-VLL channels probe masses up to about $2.9~\mathrm{TeV}$ and $2.8~\mathrm{TeV}$ in the $e^\pm h$ and $e^\pm Z$ modes, respectively. These results demonstrate that a 3 TeV CLIC can provide sensitive probes of first-generation doublet VLLs over a wide mass range, including scenarios with small VLL–electron mixing.

The first-order phase transition is central to electroweak baryogenesis and gravitational wave generation, yet thermal equilibrium effective potential analyses cannot describe the real-time non-equilibrium dynamics of the phase transition process. We use the Schwinger-Keldysh closed-time-path formalism of real-time finite-temperature field theory to study these effects. For the $\phi^6$ model, we derive the effective action and the corresponding Langevin equation. We further extend the formalism to the two scalar fields case, obtaining the coupled Langevin equations. These results provide a theoretical framework for the bubble nucleation simulation of the non-equilibrium phase transition process, laying the foundation for reliable predictions of baryogenesis and gravitational wave signals.

The nearly pure TeV-scale Higgsino dark matter provides a natural explanation for the high-energy nuclear-recoil excess reported by LUX-ZEPLIN. Such a heavy and compressed Higgsino spectrum makes direct searches at the LHC challenging. We therefore investigate complementary probes through the production and decay of heavier sparticles. We perform a comprehensive analysis and obtain the following observations: (i) For a TeV Higgsino, the current LHC Run-2 searches exclude gluino up to approximately 2.2~TeV, while the HL-LHC can give an exclusion reach of 2.5–2.6~TeV and a discovery reach of 2.3–2.4~TeV; (ii) The light-flavor squark coannihilation window lies beyond the Run-2 reach, but its lower end could be excluded at the HL-LHC under optimistic assumptions; (iii) The Run-2 search does not exclude the stop or sbottom benchmarks; (iv) The slepton and heavier-electroweakino productions are too small to access at the HL-LHC.

We derive the covariant equations of nondissipative chiral hydrodynamics from their equal-time Hamiltonian formulation and identify the Lie–Poisson structure implicit in the chiral brackets. This structure combines fluid motion with local chiral transformations. For a parity-invariant Hamiltonian quadratic in chiral charge densities and pion gradients, without external backgrounds, we derive and solve the constraints imposed by Lorentz boosts. Their coupled nonlinear sector is equivalent to the linear boost transformation laws of a symmetric tensor, which determine the velocity dependence from rest-frame data. For finite, positive rest-frame coefficients, finite ordinary-fluid energy density and thermodynamic derivatives, and a momentum–velocity relation that can be solved in either direction, the chiral Hamiltonian coefficients remain finite at every fluid speed below light speed if and only if the rest-frame pion propagation speed does not exceed the speed of light. This formulation makes symmetry constraints explicit and provides a starting point for future thermodynamically consistent dissipative extensions.

In the canonical Casimir effect, the quantum vacuum is isotropic, and the minimization of vacuum energy drives only a linear attractive force between the plates. However, the introduction of an axion gradient breaks this rotational symmetry. It can be demonstrated that these asymmetric zero-point fluctuations exert a macroscopic mechanical twist on the plates proportional to $\vec{b}^2 \sin (2\vartheta)$ where $\vec{b}$ is the spatial axion gradient and $\vartheta$ is the angle between the axion gradient and the normal to the plates.

Spontaneous symmetry breaking (SSB) is conventionally understood through static vacuum selection in low-energy approximations. However, the nonperturbative dynamical pathways connecting symmetric configurations to asymmetric states remain an open question. In this paper, we propose an operator-theoretic framework that characterizes $Z_{2}$ symmetry breaking in scalar field theory through spectral branching. Specifically, we identify an effective invariant manifold of the nonlinear Klein-Gordon equation termed the "symmetric dual breather mode," whose phase-space geometry is traced using a $t$-dependent finite-dimensional representation. Our analysis demonstrates that static SSB represents merely a small-amplitude limit ($A \ll \phi_{v1}$). As the amplitude increases into the heteroclinic regime ($A > \phi_{v1}$), the field dynamically overflows the central barrier, yielding a vanishing time-averaged order parameter ($\langle \phi \rangle = 0$) and driving a geometric curvature cancellation ($\langle V''(\phi) \rangle_{t} \to 0$). Governed by a universal scaling function $\mathfrak{F}(y)$, the logarithmic period divergence near the heteroclinic boundary naturally generates sub-eV effective mass scales without fine-tuning bare parameters. Furthermore, this dynamic barrier overflow naturally favors Majorana-like self-conjugate states over Dirac-type states. Additionally, nonlinear phase interference along the heteroclinic channel induces asymmetric phase-space contraction, decoupling the right-handed mode and dynamically giving rise to the left-handed Weyl equation. These results bridge nonperturbative wave dynamics, topological mass suppression, chiral selection, and the dynamic origin of active neutrino masses.

We study a portal of a $Z_2$-odd singlet scalar and a vector like down quark, in which a right handed flavor breaking spurion extends the portal coupling from $b_R$ to $d_R$ and $s_R$. This single coupling vector links the $b\to s$, $b\to d$, and $s\to d$ transitions. We compute the one loop dipole and $\Delta F=2$ Wilson coefficients, and show that a real scalar generates no $\Delta F=2$ amplitude at one loop. Using a seven observable profile likelihood of $B$ meson mixing, $\epsilon_K$, and radiative decays, with the CKM, lattice, and short distance inputs treated as nuisance parameters, we compare a generic spurion, minimal $U(2)^3$ with a free size of the light quark couplings, and a CKM-aligned ansatz. We have found that the present data cannot yet test the flavor structure: the Standard Model is compatible with the data, with a pseudo experiment $p$-value of $0.20$, and no direction of the light quark couplings can be excluded at 95% CL. For $M_D\simeq m_{\mathcal{S}}=1$ TeV and $|\lambda_b|=1$, the relative light quark coupling $\epsilon_R$ is bounded at 95% CL by $0.227$ for a generic spurion and by $0.211$ for minimal $U(2)^3$. More precise measurements of the $B_s$ mixing phase at the LHC and of $\sin2\beta$ at LHCb and Belle-II, together with improved lattice and CKM inputs, can make the minimality of the flavor structure testable if a deviation from the Standard Model is observed.

A model-independent measurement of the CKM angle $\beta$ can be performed using a time-dependent analysis of $B^0 \to D \pi^+ \pi^-$, $D \to K_S^0 \pi^+ \pi^-$ decays, where the Dalitz plots of both the $B$ and $D$ decays are divided into bins. The choice of binning scheme for the $B^0 \to D \pi^+ \pi^-$ Dalitz plot directly impacts the statistical sensitivity to $\beta$. This paper presents an optimization of this binning using a Fisher information-based quality factor $Q^2$ and simulated annealing. The optimized binning improves the sensitivity to $\beta$ by approximately $10\%$ relative to the equal-phase-difference baseline, as validated by toy Monte Carlo studies without experimental effects. The robustness of this improvement against decay time acceptance, Dalitz plot efficiency, Dalitz plot resolution, and background contributions is also assessed.

We present a unified Bayesian analysis of Higgs-portal, neutron-decay, and axion-like-particle (ALP)-mediated dark matter in neutron stars within the single-fluid approximation. Using a common relativistic mean-field description of hadronic matter, we combine finite-nucleus and heavy-ion collision data, chiral effective field theory, NICER measurements of four pulsars, and GW170817. The individual dark-sector parameters remain weakly determined, while model-dependent shifts in nuclear skewness reveal the sensitivity of the inferred hadronic equation of state to the assumed dark-matter mechanism. The three scenarios yield substantially overlapping mass-radius and tidal-deformability predictions, with median maximum masses near $2.1\,M_\odot$. For $1.4\,M_\odot$ stars, the Higgs-portal model predicts higher $f$-mode frequencies and shorter damping times than the neutron-decay and ALP models, although their credible regions overlap. Comparison with three consistently reanalysed two-fluid models gives the largest Bayesian evidence to neutron decay: under the adopted priors, its Bayes factors relative to the Higgs-portal and two-fluid alternatives are approximately $24$-$37$, but only $2.2$ relative to ALP. This ranking concerns complete dark-matter models and does not establish a general preference for either fluid description or evidence for a dark component itself. Improved nuclear constraints and future gravitational-wave asteroseismology could provide complementary information to disentangle the hadronic and dark-sector contributions.

This paper explores topological phase transitions in the momentum space of the $\kappa$-deformed $\phi^4$ lattice model within the mean-field approximation. We show that the double-well structure of the momentum space gives rise to degenerate momentum states at high energies and that this change is marked by a phase transition. We investigate this transition using both numerical and analytical methods, with the analytical approach based primarily on singularity theory. Our numerical analysis shows that the energy at which the topological phase transition occurs is related to the noncommutative parameter by the simple power law $E \sim 1/\alpha^{4}$. By mapping the constant-energy-level surface to the $A_{3}$ singularity, we obtain the same result analytically. We also present results unique to noncommutative systems, showing that the fraction of particles in degenerate momentum states has a nonzero commutative limit. As a nonperturbative effect, this result provides a testable prediction for the existence of noncommutative spacetime.

We propose a unified $A_4\times Z_2\times U(1)_L$ framework for generating small Dirac neutrino masses and address dark matter through feeble interactions in an extended particle physics model. The model extends the Standard Model with a pair of heavy vector-like neutral $A_4$ fermions $N(N_{L,R})$, two additional flavon fields $\eta$ and $\phi$, among which $\eta$ being a $Z_2$-odd inert scalar and a dark-sector vector-like fermion field $\chi$. We numerically explore the Dirac-sector Yukawa couplings and identify the parameter region that is consistent with the NuFit 6.1 neutrino oscillation data at the $3\sigma$ level. The dark matter candidate $\chi$, stabilized by the $Z_2$ symmetry, is produced non-thermally through the decay $N_L\rightarrow\chi+\eta$. By solving the Boltzmann equation, we find that the observed relic abundance, $\Omega_{\rm DM}h^2\simeq0.12$, can be reproduced for freeze-in couplings of order $\lambda\sim10^{-5.5}$–$10^{-7.5}$ over the considered dark matter mass range. For the chosen parameter space, we also verify the interaction rate remains below the Hubble expansion rate, confirming $\chi$ never reaches thermal equilibrium. Thus, our results demonstrate that the model provides a consistent realization of Dirac neutrino masses and FIMP dark matter within a common symmetry-based setup. The presence of light Dirac RH neutrinos can contribute to the dark radiation and hence the effective degrees of freedom via thermal and non-thermal processes. We further estimate the contribution of the light right-handed neutrinos to \(\Delta N_{\rm eff}\), finding a maximum characteristic value of \(\Delta N_{\rm eff}\simeq0.14\) in the benchmark parameter region.

The extension of the LUX–ZEPLIN nuclear-recoil analysis to approximately $270\,\mathrm{keV}$ probes a qualitatively new dark-matter regime in which endothermic scattering can suppress conventional low-energy recoils and concentrate the surviving spectrum near the Galactic high-velocity tail. We construct a modular-$S_4$ realization in which a minimal $2N_R+2S$ inverse seesaw accounts for lepton flavor, while a separate pair of Standard-Model-singlet fermions forms the pseudo-Dirac state relevant for high-recoil xenon scattering. The sectors share a common complex modulus $\tau$, so the modular forms selected by charged-lepton and neutrino data also enter the operators generating the dark Dirac mass and Majorana splitting. Our scan yields $181447$ lepton-sector solutions satisfying $\chi^2_{\ell+\nu}<30$, distributed among several disconnected modular regions, and predicts one effectively massless light neutrino at leading order. Restoring the physical scales allows TeV-scale heavy quasi-Dirac neutral fermions with small non-unitarity. We subsequently scan $2\times10^6$ dark-sector points only over flavor-accepted values of $\tau$ and identify common-modulus solutions in the LZ-oriented region $300\,\mathrm{GeV}\le m_\chi\le2\,\mathrm{TeV}$ and $300\,\mathrm{keV}\le\delta\le400\,\mathrm{keV}$. An exploratory two-bin Poisson likelihood, including endothermic xenon kinematics, the Helm form factor, Standard-Halo-Model velocities, Gaussian energy smearing, and profiling over the signal normalization, gives a best grid point at $(m_\chi,\delta)\simeq(1.847\,\mathrm{TeV},371.5\,\mathrm{keV})$, close to the terrestrial inelastic kinematic ceiling. The construction provides a direct link between modular lepton flavor, TeV-scale inverse-seesaw dynamics, and high-recoil inelastic dark matter.

Fast radio bursts (FRBs) probe free-electron columns along cosmological sightlines through their dispersion measures (DMs), whereas baryon acoustic oscillations (BAO) constrain cosmic expansion geometry through acoustic distance ratios. In this work, we leverage their distinct physical sensitivities to simultaneously determine the Hubble constant ($H_0$) and cosmic baryon density ($\Omega_{\rm b}$) without external cosmic microwave background (CMB) or Big Bang nucleosynthesis (BBN) priors. Combining 120 localized FRBs and DESI DR2 BAO, we obtain $H_0=71.4^{+2.2}_{-2.5}\ {\rm km\ s^{-1}\ Mpc^{-1}}$ and $\Omega_{\rm b}=0.0503^{+0.0025}_{-0.0021}$ in $\Lambda$CDM, corresponding to precisions of $3.3\%$ and $4.6\%$, respectively. The inferred $H_0$ is statistically consistent with both SH0ES and CMB, and $\Omega_{\rm b}$ agrees with the joint constraint from BBN and CMB. Adopting IllustrisTNG-based DM distributions and fixing the diffuse-gas baryon fraction tightens the constraint to $H_0=68.8\pm1.0\ {\rm km\ s^{-1}\ Mpc^{-1}}$, but lowers the central value toward the CMB-inferred value, identifying extragalactic DM modeling as the dominant systematic uncertainty. These results establish FRB-BAO complementarity as a new avenue for simultaneously constraining $H_0$ and $\Omega_{\rm b}$.

We formulate massless tree-level Compton scattering as an effective two-qubit operation on electron and photon helicities. In the Bell basis, the scattering map separates into two parity sectors and admits a simple quantum circuit representation with one nonunitary filter. After Kraus normalization, this filter defines an unsharp incomplete Bell measurement that distinguishes the two Bell-parity sectors but not the relative Bell label within each sector. We further show that the incomplete measurement alone does not surpass the classical teleportation threshold, whereas a subsequent complete Bell-basis readout enables unit conditional teleportation fidelity.

The recent observation of an excess near the kinematic $t\bar{t}$ production threshold by the CMS and ATLAS collaborations suggests the existence of a color-singlet and $S$-wave quasi-bound state of top quark. Due to the non-relativistic nature of top and anti-top quarks in this threshold region, toponium production provides an ideal system to probe the anomalous dipole moments of the top quark. In this work, we investigate the impact of chromo-electric dipole moment (CEDM) in $t\bar{t}$-gluon vertex on toponium production at the LHC. We implement the enhanced near-threshold production of the spin-0 color-singlet toponium state $\eta_t$ via gluon fusion. The resonant toponium contribution is then combined with the continuum $t\bar{t}$ production amplitude, including the interference effects induced by the top CEDM. Furthermore, we construct a set of asymmetries based on the angular distributions of charged leptons in the leptonic decay channel of $t\bar{t}$. Finally, we derive the expected exclusion limit on the top quark CEDM parameter $d_t^g$ using these lepton angular asymmetries.

Three hadronic-bond mechanisms were proposed in our previous studies to describe near-threshold exotic hadrons in terms of hadronic molecular configurations: the covalent bond arises from the sharing and exchange of valence light quarks between hadronic clusters, the creation bond originates from the activation of coherent sea $q\bar{q}$ degrees of freedom followed by the formation of effective covalent correlations, and the annihilation bond arises from valence $q\bar{q}$ annihilation and the associated mixing with a nearby compact state. A simple toy model was previously constructed only for the covalent bond, and in the present study we extend this model to incorporate the creation and annihilation bonds within a unified framework. The resulting framework organizes covalent-bond configurations as tending to lie below threshold and creation-bond configurations as tending to appear above threshold, while the annihilation bond can shift a pre-existing molecular configuration either downward or upward through mixing with a nearby compact state. An effective activation energy $E_{\rm{act}}$ is introduced for the coherent sea four-quark component involved in the creation bond, with the $Z_c(3900)$ providing the benchmark value $E_{\rm{act}}\sim17~{\rm{MeV}}$. Intriguingly, this value is numerically close to the reported mass of the $X_{17}$ particle, which we previously interpreted as a low-energy bare four-quark structure. This numerical proximity may therefore reflect common low-energy (four-quark) dynamics, although the microscopic connection remains to be established. For the isoscalar $D^*\bar{D}^*B^*\bar{B}^*$ configuration involving the $Z_c(4020)$ and $Z_b(10650)$ creation-bond subsystems linked by two additional covalent bonds, we estimate a binding energy of approximately $36~{\rm{MeV}}$ below its four-meson threshold and propose searches in the $4\mu$ and $4\mu2\pi$ final states.

We study the entanglement structure of gravitons in quasicrystalline inflation. Both parity-even and parity-odd interactions generate graviton pairs with nonzero total momentum. For opposite-helicity pairs with identical momenta, the parity-even contribution can be nonzero, whereas the parity-odd contribution vanishes. The transition from inflation to radiation domination produces additional conventional two-mode squeezing. We derive the resulting normal and anomalous covariances. The initially nonzero reciprocal blocks of the full field-momentum covariance remain nonzero under homogeneous evolution, although individual components can vanish. We show that this homogeneous, helicity-preserving evolution acts unitarily within each helicity sector and therefore preserves the entanglement between the complete right- and left-helicity sectors. Nevertheless, it can eliminate entanglement in the reduced state of a co-propagating pair. We illustrate this distinction using a solvable four-mode model.

The structures in the di-J/psi spectrum seen at the LHC are widely read as fully charmed tetraquarks. As an alternative scenario, the $2^{++}$ production amplitude for a compact $cc\bar c\bar c$ source rescattering through ten charmonium-pair channels is presented. The model is completely fixed except for three background parameters and provides a competitive description of the data, with chi-sq/ndf=56/50. Prominent features are driven by J/psi psi(nS) thresholds or threshold enhancement, with no need for exotic hadrons.

Recently, the possibility of having sterile Majorana neutrinos charged under $B-L$ gauge symmetry in the bulk of the dark dimension has been explored. We point out a cosmological restriction on the Majorana mass of bulk neutrinos leading to mass $\gtrsim 100~{\rm GeV}$. This avoids the over-production of Kaluza-Klein neutrino towers in the early universe thus resolving the cosmological neutrino catastrophe of extra dimension scenarios. If the mass of the bulk neutrino is at the lower end of this bound, it can potentially also explain the recently observed Fermi halo excess on gamma rays through the evaporation of long-lived 5d (i.e. dark) black holes through Hawking radiation to bulk neutrinos, which promptly decay into standard model particles.

We calculate higher-order perturbative corrections for $t{\bar t}H$ production. By adding second-order and third-order soft-gluon corrections to NLO QCD and NLO electroweak (EW) results, we present total and differential cross sections at LHC energies through approximate N$^3$LO (aN$^3$LO) in QCD and NLO in EW. Our aN$^3$LO QCD + NLO EW results provide significant enhancements and a reduced scale dependence for the cross section and the top-quark transverse-momentum and rapidity distributions.

We present BSMScanner, a framework in which a beyond-the-Standard-Model (BSM) parameter scan is specified as a set of declarative YAML documents rather than written as a program. The user declares the free parameters and their priors, the mass matrices and the diagonalisations that act on them, the observables, the theory-validity conditions and the likelihood terms. The framework validates this specification, resolves it into a dependency graph and compiles it once into a typed C++ evaluation kernel, which is then driven by an independently chosen scanning engine: uniform sampling, two differential-evolution engines, or a staged basin-discovery orchestrator, optionally followed by Markov-chain posterior refinement. Flavour physics matrix diagonalisation, PMNS and CKM construction in fixed conventions, tabulated oscillation likelihoods and a library of common flavour observables are provided by the framework and imported by name, so that a model file contains only model-specific definitions; quantities without a closed form, such as a relic density, enter through a C++ or Python plugin interface. We describe the specification schema, the observable and likelihood library, the scanning engines and their configuration, and demonstrate the framework on six benchmark models with $4$ to $26$ free parameters, giving for each the specification, the scan configuration, the resulting best fit and analytic cross-checks of the result.

We calculate the masses of the $J^P=\frac{1}{2}^-$ hidden-charm pentaquark states in the $SU(3)$ decuplet within the heavy pentaquark chiral perturbation theory (HPChPT) up to the next-to-leading order (NLO). The one-loop self-energy corrections from the $\pi$, $K$, and $\eta$ mesons are evaluated. Taking $P_\psi^N(4312)$ and $P_{\psi s}^\Lambda(4459)$ as inputs, we predict the masses of the doubly-strange and triply-strange decuplet members $P_{\psi ss}^N$ and $P_{\psi sss}^\Lambda$ to be 4.607 GeV and 4.755 GeV, respectively. The mass splittings between adjacent strangeness layers are nearly constant at approximately 0.148 GeV. This equal-spacing pattern follows directly from the analytical structure of the NLO chiral corrections, while its actual magnitude is set by the low-energy constants (LECs). It indicates that the Gell–Mann–Okubo (GMO) relation, expected at the leading order of SU(3) flavor symmetry breaking, persists to good accuracy at the NLO.

An eV-scale sterile Majorana neutrino can suppress neutrinoless double-beta decay through destructive interference with the active-neutrino contribution, weakening the resulting constraints on sterile-neutrino parameters. We investigate how complementary beta-decay information restricts this cancellation in the 3+1 framework. Using updated oscillation parameters that include the first JUNO results, we determine the allowed sterile-neutrino mass and mixing regions for both normal and inverted ordering. We show that an upper limit on the effective beta-decay mass $m_\beta$ of the three light neutrinos strengthens the constraints from neutrinoless double-beta decay alone. The beta-decay bound restricts the light-neutrino masses and hence the cancellation between the active and sterile contributions to $m_{\beta\beta}$. We derive analytic expressions for the resulting boundaries and use complex-plane geometry to explain the allowed values of the sterile Majorana phase $\alpha_4$ for a finite $|m_{\beta\beta}|$ limit. For the mixing considered, normal ordering allows a broad range of $\alpha_4$ at small sterile masses, whereas inverted ordering favors values near $\pi$. The allowed phase range narrows as the sterile mass approaches its upper bound or the limit on $|m_{\beta\beta}|$ becomes more stringent.

Soon after Maxwell's celebrated synthesis of electrodynamics, the discovery of the electron raised fundamental questions about the nature and structure of elementary particles. The picture of a small, rigid, charged body of finite radius faced the difficulty of introducing non-electromagnetic forces or stresses to prevent the charge from dispersing, an assumption that was increasingly regarded as unsatisfactory. The alternative description in terms of a point charge was no more satisfactory, because its electromagnetic self-energy diverges. From the early twentieth century onward, several authors therefore explored modifications of Maxwell's theory, with nonlinear electrodynamics emerging as a particularly natural and radical possibility. In this paper, we revisit at the undergraduate level some of the nonlinear theories proposed in this context and explore their ability to address the classical self-energy problem of charged particles.

We investigate the gravitational waves generated by first-order phase transitions (PTs) in an expanding Universe. Using a scalar field-fluid coupled model, we perform three-dimensional lattice numerical simulations of slow first-order PTs with strong strength. We observe that the contribution from sound waves to the gravitational wave (GW) signal significantly dominates over that from bubble collisions. The sound wave spectra exhibit two peaks located at the mean bubble separation and the sound-shell width. Rotational modes are generated in the fluid during the bubble collisions, and their magnitude grows with the PT strength. The lifetime of the sound wave source increases with decreasing $\alpha$: for weaker transitions the source can persist for longer than a Hubble time, while for stronger transitions it decays within a Hubble time. When the walls propagate as deflagrations, the GW spectral shape changes drastically, with steeper ultraviolet tails and a shorter-lived sound wave source. We also observe that the magnitude of the normalized GWs is roughly an order of magnitude smaller than obtained in the Minkowski spacetime simulations.

In the present work, we investigate the production of $\chi_{c0}$ in the $\bar{\Lambda} n \rightarrow \chi_{c0} K^{0}_{S}$ process by utilizing an effective Lagrangian approach. Based on the $\chi_{c0} \rightarrow n K^{0}_{S} \bar{\Lambda}$ decay observed by the BESIII Collaboration, the coupling constants are determined by fitting the $M_{K^{0}_{S} \bar{\Lambda}}$ and $M_{n K^{0}_{S}}$ invariant mass spectra, where eight $N$ and $\Lambda$ state are considered. Moreover, the parameters $\beta$ is taken to be 1, 2, 3 as special cases to check the parameter dependence. Our results show that two clear structures can be observed in both $M_{K^{0}_{S} \bar{\Lambda}}$ and $M_{n K^{0}_{S}}$ invariant mass spectra, which should correspond to $N(1720)/N(1895)$ and $\Lambda(1600)/\Lambda(1890)$, respectively. In addition, the contributions from $N(938)$ and $\Lambda(1116)$ intermediate states are much smaller than those of the above-threshold resonances. With the fitted parameters for $\beta=1$, 2, 3, the cross sections for $\bar{\Lambda} n \rightarrow \chi_{c0} K^{0}_{S}$ are estimated to be 1.9 nb, 4.2 nb, and 8.0 nb at $\sqrt{s}=6$ GeV, respectively. Furthermore, our estimations indicate that the differential cross sections for $\bar{\Lambda} n \rightarrow \chi_{c0} K^{0}_{S}$ reach a maximum in the forward angle region.

A mixed leptogenesis source and its low-energy neutrino portal depend on the same heavy-particle amplitudes. We determine how this common origin restricts matching cancellations and the scalar population produced during reheating. For two Majorana mass levels, each containing a degenerate pair, the inclusive lepton-number-violating invariant fixes an allowed norm domain for the mixed dimension-five coefficient at specified threshold strengths. An aligned flavour texture makes the conventional source vanish as a matrix and gives equal coupling norms for the two massive neutrinos. A continuous family preserves the neutrino-mass fit while relating the source to unequal light coupling strengths. The matched couplings give benchmark vacuum lifetimes of $1.62\times10^{12}\,\mathrm{s}$ and $2.80\times10^{11}\,\mathrm{s}$, while reheating normalized to the baryon abundance determines the primary spectrum. In the massless Born approximation with dilute outgoing states, bath-produced scalars carry $4.81\times10^{-5}$ of the primary scalar energy but contribute $11.1$ times its variance. The positive production functional converts the matching constraint into a conditional variance bound. We derive the scalar-mass dependence of stimulated emission and the Hartree moment equation, keeping the scalar mass and quartic as renormalized matching inputs. These results link the leptogenesis source to light-neutrino decay and the finite-density quantities entering subsequent coupled transport.

Most of the mass of the visible universe originates from the strong interaction. Quantitatively reproducing the origin of the nucleon mass is one of the important challenges in fundamental science. Since the next-generation Electron-Ion Collider has identified resolving this problem as one of its major goals, further theoretical studies are needed to develop approaches to investigating the origin experimentally. In this paper, we explore the possibility of evaluating the “gluon condensate term” which is particularly difficult to determine among the contributions to the nucleon mass, using high-energy scattering experiments. We first express the gluon condensate term in terms of experimentally accessible twist-4 lightcone matrix elements. We then derive, for the first time, analytic formulas for the cross section including all twist-4 contributions from pure quark, quark-gluon, and pure gluon matrix elements in $ep$ collisions, and show how these contributions can be related to the gluon condensate term.