We investigate the radial density distribution of the dynamical dark energy inside the white dwarfs (WDs) and its possible impact on their intrinsic structure. The minimally coupled dark energy with the barotropic equation of state, which has three free parameters (density, equation of state, and effective sound speed), is used. We analyze how such dark energy affects the mass-radius relation for the WDs because of its contribution to the joint gravitational potential of the system. For this we use the Chandrasekhar model of the WDs, where model parameters are the parameter of the chemical composition and the relativistic parameter. To evaluate the dark energy distribution inside a WD we solve the conservation equation in the spherical static metric. The obtained distribution is used to find the parameters of dark energy for which the deviation from the Chandrasekhar model mass-radius relation become non-negligible. We conclude also that the absence of observational evidence for the existence of WDs with untypical intrinsic structure (mass-radius relation) gives us lower limits for the value of an effective sound speed of dark energy $c_s^2\gtrsim {10}^{-4}$ (in units of speed of light).

Combining the recent developments of the observations of $\mathrm{\Omega }$ sates we calculate the $\mathrm{\Omega }$ spectrum up to the $N=2$ shell within a nonrelativistic constituent quark potential model. Furthermore, the strong and radiative decay properties for the $\mathrm{\Omega }$ resonances within the $N=2$ shell are evaluated by using the masses and wave functions obtained from the potential model. It is found that the newly observed $\mathrm{\Omega }(2012)$ resonance is most likely to be the spin-parity $J^P=3/2^{-}$ $1P$-wave state $\mathrm{\Omega }(1^2{P}_{3/2^{-}})$, it also has a large potential to be observed in the $\mathrm{\Omega }(1672)\gamma$ channel. Our calculation shows that the $1P$-, $1D$-, and $2S$-wave $\mathrm{\Omega }$ baryons have a relatively narrow decay width of less than 50 MeV. Based on the obtained decay properties and mass spectrum, we further suggest optimum channels and mass regions to find the missing $\mathrm{\Omega }$ resonances via the strong and/or radiative decay processes.

We derive mass formulas for the $P$-wave orbitally excited $D_{0(s)}^{*}$, $D_{1(s)}^{\prime }$, $D_{1(s)}$, and $D_{2(s)}^{*}$ heavy charmed mesons including all effects from one-loop corrections that contribute at leading order in chiral expansion. In our formalism, the effects to first order in $m_q$, where $m_q$ is the light quark mass, and to first order in $m_c^{-1}$, where $m_c$ is the charm quark mass, and $m_q/m_c$ terms are considered. The experimental and lattice QCD results on the charmed meson spectra are employed to fix the large number of counterterms appearing in the effective chiral Lagrangian used in this work. This allows us to test the validity of perturbative expansion of our theory. The results presented in the current paper are useful to other applications of excited charmed and bottom meson systems.

In the framework of the chiral quark model along with complex scaling range, we perform a dynamical study on the low-lying $S$-wave double-heavy tetraquark states ($QQ\overline{q}\overline{q}$, $Q=c$, $b$ and $q=u$, $d$) with an accurate computing approach, Gaussian expansion method. The meson-meson and diquark-antidiquark configurations within all possible color structures for spin-parity quantum numbers $J^P=0^{+}$, $1^{+}$, and $2^{+}$ and in the 0 and 1 isospin sectors are considered. Possible tightly bound and narrow resonance states are obtained for double-charm and double-bottom tetraquarks with $I{J}^P=01^{+}$, and these exotic states are also obtained in charm-bottom tetraquarks with $00^{+}$ and $01^{+}$ quantum numbers. Only a loosely bound state is found in charm-bottom tetraquarks of $02^{+}$ states. All of these bound states within meson-meson configurations are loosely bound whether in color-singlet channels or coupling to hidden-color ones. However, compact structures are available in diquark-antidiquark channels except for charm-bottom tetraquarks in $02^{+}$ states.

The unified approach of Feldman and Cousins allows for exact statistical inference of small signals that commonly arise in high energy physics. It has gained widespread use, for instance, in measurements of neutrino oscillation parameters in long-baseline experiments. However, the approach relies on the Neyman construction of the classical confidence interval and is computationally intensive as it is typically done in a grid-based fashion over the entire parameter space. In this article, we propose an efficient algorithm for the Feldman-Cousins approach using Gaussian processes to construct confidence intervals iteratively. We show that in the neutrino oscillation context, one can obtain confidence intervals fives times faster in one dimension and ten times faster in two dimensions, while maintaining an accuracy above 99.5%.

The thermodynamic properties of the Bañados-Teitelboim-Zanelli black hole endowed with Korteweg–de Vries (KdV)-type boundary conditions are reconsidered. This family of boundary conditions is labeled by a non-negative integer $n$, and gives rise to a dual theory which possesses anisotropic Lifshitz scaling invariance with dynamical exponent $z=2n+1$. We show that from the scale invariance of the action for stationary and circularly symmetric spacetimes, an anisotropic version of the Smarr relation arises. Finally, we analyze the global and local thermal stability of the system and we found that the specific heat of the black hole is positive for all possible values of $z$, and at the self-dual temperature $T_s=\frac{1}{2\pi }(\frac{1}{z}{)}^{\frac{z}{z+1}}$, there is a Hawking-Page phase transition between the BTZ black hole and thermal ${\mathrm{AdS}}_3$ spacetime.

An $I$-ball/oscillon is a solitonlike oscillating configuration of a real scalar field, and defined as a minimum energy state for a given adiabatic invariant. It lasts for a long time because of the approximate conservation of their adiabatic invariant. In this paper, we examine the stability of a special type of $I$-ball/oscillon, the “exact” $I$-ball/oscillon, whose adiabatic invariant is exactly conserved. We show that the exact $I$-ball/oscillon is generally stable in classical field theory, but one with a certain adiabatic invariant is unstable against small perturbations because fluctuations around the exact $I$-ball/oscillon profile have instability bands. Accordingly, the exact $I$-ball/oscillon breaks up in the presence of the fluctuations of corresponding instability modes. We also confirm the fragileness of the exact $I$-ball/oscillon by the classical lattice simulation.

For field theories in curved spacetime, defining how matter gravitates is part of the theory building process. In this paper, we adopt Bekenstein’s multiple geometries approach to allow part of the matter sector to follow the geodesics on a general pseudo-Riemannian geometry, constructed from a tensor and a $U(1)$ gauge field. This procedure allows us to generate a previously unknown corner of vector-tensor theories. In the Jordan frame, apparent high-derivative terms of the vector field are reduced by integrating out an auxiliary variable, at the cost of introducing new matter interactions. As a simple example, we consider a conformal relation between different geometries and demonstrate the presence of an auxiliary degree. We conclude with a discussion of applications, in particular for the early universe.

We study charged Dirac quasinormal modes (QNMs) on Reissner-Nordström–anti–de Sitter (RN-AdS) black holes with generic Robin boundary conditions, by extending our earlier work of neutral Dirac QNMs on Schwarzschild-AdS black holes. We first derive the equations of motion for charged Dirac fields on a RN-AdS background. To solve these equations we impose a requirement on the Dirac field: that its energy flux should vanish at asymptotic infinity. A set of two Robin boundary conditions compatible with QNMs is consequently found. By employing both analytic and numeric methods, we then obtain the quasinormal spectrum for charged Dirac fields and analyze the impact of various parameters, in particular of electric charges. An analytic calculation shows explicitly that the charge coupling between the black hole and the Dirac field does not trigger super-radiant instabilities in the small black hole and low frequency limit. Numeric calculations, on the other hand, show quantitatively that Dirac QNMs may change substantially due to the electric charge. Our results illustrate how vanishing energy flux boundary conditions, as a generic principle, are applicable not only to neutral but also to electrically charged fields.

We construct solutions within Jackiw-Teitelboim (JT) gravity in the presence of nontrivial couplings between the dilaton and the Abelian 1-form where we analyze the asymptotic structure as well as the phase stability corresponding to charged black hole solutions in $1+1\mathrm{D}$. We consider the Almheiri-Polchinski model as a specific example within $1+1\mathrm{D}$ JT gravity which plays a pivotal role in the study of Sachdev-Ye-Kitaev (SYK)/anti–de Sitter (AdS) duality. The corresponding vacuum solutions exhibit a rather different asymptotic structure than their uncharged counterpart. We find interpolating vacuum solutions with ${\mathrm{AdS}}_2$ in the IR and ${\mathrm{Lifshitz}}_2$ in the UV with dynamical exponent $z_{\mathrm{dyn}}=3/2$. Interestingly, the presence of charge also modifies the black hole geometry from asymptotically AdS to asymptotically Lifshitz with the same value of the dynamical exponent. We consider specific examples, where we compute the corresponding free energy and explore the thermodynamic phase stability associated with charged black hole solutions in $1+1\mathrm{D}$. Our analysis reveals the existence of a universal thermodynamic feature that is expected to reveal its immediate consequences on the dual SYK physics at finite density and strong coupling.

We present the derivation of the Casimir-Polder interactions mediated by a massive photon between two neutral systems described in terms of their atomic polarizability tensors. We find a compact expression for the leading term at large distances between the two systems. Our result reduces, in the massless photon limit, to the standard Casimir-Polder. We discuss implications of our findings with respect to recent scenarios of physics beyond the standard model such as universal extra dimensions, Randall-Sundrum and scale-invariant models. For each model we compute the correction to the Casimir-Polder interaction in terms of the free parameters.

We study the impact of $R$-parity violating supersymmetry (RPV SUSY) on the 125 GeV Higgs production and decay modes at the LHC. We assume a heavy SUSY spectrum with multi-TeV squarks and SU(2) scalar singlets as well as the decoupling limit in the SUSY Higgs sector. In this case the lightest $CP$-even Higgs is SM-like when $R$-parity is conserved. In contrast, we show that when R-parity violating interactions are added to the SUSY framework, significant deviations may occur in some production and decay channels of the 125 GeV Higgs-like state. Indeed, we assume a single-flavor (mostly third generation) Bilinear RPV (BRPV) interactions, which generate Higgs-sneutrino mixing, lepton-chargino mixing and neutrino-neutralino mixing, and find that notable deviations of $\mathcal{O}(20-30\%)$ may be expected in the Higgs signal strength observables in some channels, e.g., in $pp\to h\to {\mu }^{+}{\mu }^{-}$, ${\tau }^{+}{\tau }^{-}$. Moreover, we find that new and detectable signals associated with BRPV Higgs decays to gauginos, $h\to {\nu }_{\tau }{\tilde{\chi }}_2^0$ and $h\to {\tau }^{\pm }{\chi }_2^{\mp }$, may also arise in this scenario. These decays yield a typical signature of $h\to {\tau }^{\pm }{\ell }^{\mp }+{\cancel{E}}_T$ ($\ell =e$, $\mu$, $\tau$) that can be much larger than in the SM, and may also be accompanied by an $\mathcal{O}(20-30\%)$ enhancement in the diphoton signal $pp\to h\to \gamma \gamma$. We also examine potential interesting signals of Trilinear R-parity violation (TRPV) interactions in the production and decays of the Higgs-sneutrino BRPV mixed state (assuming it is the 125 GeV scalar) and show that, in this case also, large deviations up to $\mathcal{O}(100\%)$ are expected in e.g., $pp\to h\to {\mu }^{+}{\mu }^{-}$, ${\tau }^{+}{\tau }^{-}$, which are sensitive to the $\mathrm{BRPV}\times \mathrm{TRPV}$ coupling product.

We study the experimental constraints on a model of a two-component dark matter, consisting of the QCD axion, and a scalar particle, both contributing to the dark matter relic abundance of the Universe. The global Peccei-Quinn symmetry of the theory can be spontaneously broken down to a residual ${\mathbb{Z}}_2$ symmetry, thereby identifying this scalar as a stable weakly interacting massive particle, i.e., a dark matter candidate, in addition to the axion. We perform a comprehensive study of the model using the latest data from dark matter direct and indirect detection experiments, as well as new physics searches at the Large Hadron Collider. We find that although the model is mostly constrained by the dark matter detection experiments, it is still viable around a small region of the parameter space where the scalar dark matter is half as heavy as the Standard Model Higgs. In this allowed region, the bounds from these experiments are evaded due to a cancellation mechanism in the dark matter–Higgs coupling. The collider search results, however, are shown to impose weak bounds on the model.

Background-field methods provide an important nonperturbative formalism for the determination of hadronic properties which are complementary to matrix-element calculations. However, new challenges are encountered when utilizing a fermion action exposed to additive mass renormalizations. In this case, the background field can induce an undesired field-dependent additive mass renormalization that acts to change the quark mass as the background field is changed. For example, in a calculation utilizing Wilson fermions in a uniform background magnetic field, the Wilson term introduced a field-dependent renormalization to the quark mass which manifests itself in an unphysical increase of the neutral-pion mass for large magnetic fields. Herein, the clover-fermion action is studied to determine the extent to which the removal of $\mathcal{O}(a)$ discretization errors suppresses the field-dependent changes to the quark mass. We illustrate how a careful treatment of nonperturbative improvement is necessary to resolve this artifact of the Wilson term. Using the ${32}^3\times 64$ dynamical-fermion lattices provided by the PACS-CS Collaboration we demonstrate how our technique suppresses the unphysical mass renormalization over a broad range of magnetic-field strengths.

We present two new suggestions for density of states (DoS) approaches to finite density lattice QCD. Both proposals are based on the recently developed and successfully tested DoS functional fit approach (FFA) technique, which is a DoS approach for bosonic systems with a complex action problem. The two different implementations of DoS FFA we suggest for QCD make use of different representations of finite density lattice QCD in terms of suitable pseudofermion path integrals. The first proposal is based on a pseudofermion representation of the grand canonical QCD partition sum, while the second is a formulation for the canonical ensemble. We work out the details of the two proposals and discuss the results of exploratory two-dimensional test studies for free fermions at finite density, where exact reference data allow one to verify the final results and intermediate steps.

Using a data sample of $921.9{\mathrm{fb}}^{-1}$ collected with the Belle detector, we study the process of $e^{+}{e}^{-}\to D_s^{+}{D}_{s1}(2536{)}^{-}+\mathrm{c}.\mathrm{c}.$ via initial-state radiation. We report the first observation of a vector charmoniumlike state decaying to $D_s^{+}{D}_{s1}(2536{)}^{-}+\mathrm{c}.\mathrm{c}.$ with a significance of $5.9\sigma$, including systematic uncertainties. The measured mass and width are $({4625.9}_{-6.0}^{+6.2}(\text{stat})\pm 0.4(\text{syst}))\mathrm{MeV}/c^2$ and $({49.8}_{-11.5}^{+13.9}(\text{stat})\pm 4.0(\text{syst}))\mathrm{MeV}$, respectively. The product of the $e^{+}{e}^{-}\to D_s^{+}{D}_{s1}(2536{)}^{-}+\mathrm{c}.\mathrm{c}.$ cross section and the branching fraction of $D_{s1}(2536{)}^{-}\to {\overline{D}}^{*0}{K}^{-}$ is measured from the $D_s{\overline{D}}_{s1}(2536)$ threshold to 5.59 GeV.

We consider the special roles of the zero loci of the Weierstrass invariants $g_2(\tau (z))$ and $g_3(\tau (z))$ in F theory on an elliptic fibration over ${\mathbb{P}}^1$ or a further fibration thereof. They are defined as the zero loci of the coefficient functions $f(z)$ and $g(z)$ of a Weierstrass equation. They are thought of as complex codimension-1 objects and correspond to the two kinds of critical points of a dessin d’enfant of Grothendieck. The ${\mathbb{P}}^1$ base is divided into several cell regions bounded by some domain walls extending from these planes and D-branes, on which the imaginary part of the $J$ function vanishes. This amounts to drawing a dessin with a canonical triangulation. We show that the dessin provides a new way of keeping track of mutual nonlocalness among 7-branes without employing unphysical branch cuts or their base point. With the dessin, we can see that weak- and strong-coupling regions coexist and are located across an $S$ wall from each other. We also present a simple method for computing a monodromy matrix for an arbitrary path by tracing the walls it goes through.

We present a covariant quantization of the “massive” spin-$\frac{3}{2}$ Rarita-Schwinger field in de Sitter (dS) spacetime. The dS group representation theory and its Wigner interpretation combined with the Wightman-Gärding axiomatic and analyticity requirements in the complexified pseudo-Riemanian manifold constitute the basis of the quantization scheme, while the whole procedure is carried out in terms of coordinate-independent dS plane waves. We make explicit the correspondence between unitary irreducible representations of the dS group and the field theory in dS spacetime; by “massive” is meant a field that carries a particular principal series representation of the dS group. We drive the plane-wave representation of the dS massive Rarita-Schwinger field in a manifestly dS-invariant manner. We show that it exactly reduces to its Minkowskian counterpart when the curvature tends to zero as far as the analyticity domain conveniently chosen. We then present the Wightman two-point function fulfilling the minimal requirements of local anticommutativity, covariance, and normal analyticity. The Hilbert space structure and the unsmeared field operator are also defined. The analyticity properties of the waves and the two-point function that we discuss in this paper allow for a detailed study of the Hilbert space of the theory, and give rise to the thermal physical interpretation.