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In this paper, we have presented the cosmological model in Brans–Dicke theory (BDT) of gravity for a Bianchi type-IX spacetime. We obtained the exact solutions of the field equations by applying the new form of deceleration parameter, i.e. fractional linear varying deceleration parameter (FLVDP) as proposed by R. K. Mishra and A. Chand [Astrophys. Space Sci. 361, 1 (2016)]. In this paper, we have also presented the physical and geometric properties and mathematical analysis of the proposed model. Then we have provided the energy conditions and statefinder diagnostic. [ABSTRACT FROM AUTHOR]

The aim of this paper is to obtain magnetic trajectories corresponding to contact magnetic fields in Lorentzian α -Sasakian 3-manifolds. First, we provide the definitions of the magnetic field and the Lorentzian equation used in this paper and derive the expression for the Bott connection by using the Levi-Civita connection. Then we derive the expression of Killing vector fields by using the Killing equation. At the same time, we obtain the explicit formulas for the Killing magnetic curves related to Bott connection. In addition, we provide an example for each type of Killing magnetic curve. [ABSTRACT FROM AUTHOR]

In this paper, we construct the quantum fields of three types of universal characters corresponding to partition shapes π = (3) , π = (2 , 1) and π = (1 3) and derive the commutation relations of quantum fields. By acting the quantum fields on the constant function 1 , the generating functions of three types of universal characters have been investigated. Furthermore, we discuss three integrable systems characterized by (3) -type, (2 , 1) -type and (1 3) -type universal characters. [ABSTRACT FROM AUTHOR]

In this paper, we study the evolution of the FRW universe filled with variable modified Chaplygin gas (VMCG). We begin with a thermodynamical treatment of VMCG described by the equation of state P = A ρ − B ρ − α , and obtain its temperature as a function of redshift z. We show that the results are consistent with similar works on other types of Chaplygin gas models. In addition to deriving the exact expression of temperature of the fluid in terms of the boundary conditions and redshift, we also used observational data to determine the redshift at the epoch of transition from the decelerated to the accelerated phase of expansion of the universe. The values of other relevant parameters like the Hubble parameter, the equation-of-state parameter and the speed of sound are obtained in terms of the redshift parameter, and these values are compared with the results obtained from previous works on MCG and other Chaplygin gas models for the various values of n permitted by thermodynamic stability. We assume the present value of temperature of the microwave background radiation to be given by T 0 = 2. 7 K , and the parameter A in the equation of state is taken as 1 / 3 since it corresponds to the radiation-dominated phase of the universe. The value of the parameter Ω x has been assumed to be 0. 7 in our calculation. Since it is known that the redshift of photon decoupling is z ≃ 1 1 0 0 , we used this value to calculate the temperature of decoupling. [ABSTRACT FROM AUTHOR]

In this paper, we study an effective field theory (EFT) for a singlet scalar extension of the standard model (SM). The tree- and one-loop level effective actions are derived by integrating out the heavy singlet scalar in the Lagrangian for the UV theory and by applying to the functional method, respectively. In the UV model, the light scalar field identified with the SM Higgs is assumed to be massless in the symmetric phase. When the heavy singlet scalar acquires a vacuum expectation value, the Z 2 symmetry is broken and a mass term of the light scalar is induced. In light of EFT we derive, the electroweak vacuum resulting in 126 GeV Higgs mass can be attained when the induced squared-mass term of the light scalar in the scalar potential becomes negative. This condition can occur when the constant of the scalar coupling between the two different scalars is allowed to be negative. We investigate how the EFT can be constrained by theory and experiments. We also examine whether or not electroweak phase transition (EWPT) in this scenario can be a first order. Some numerical results leading to the first-order EWPT while satisfying the constraints studied are presented. [ABSTRACT FROM AUTHOR]

Seldom quantum secret sharing protocols with both the flexible (t, n) threshold and semi-quantum properties have been proposed. Recently, a novel idea of (t, n) threshold semiquantum secret sharing was proposed, which has both the (t, n) threshold and semi-quantum properties. Its idea can simplify the quantum secret sharing process such that many classical users with simple ability of quantum operations can realize the communication goal by cooperating with one quantum party. Furthermore, the protocol is very flexible since any t collaborators of the n classical users can reconstruct the full secret by Shamir's threshold technology. Unfortunately, their protocol is vulnerable to the NOT-gate attack. This paper shows that an attacker can break the (t, n) threshold protocol by performing two rounds of NOT-gate attack. Then, an improved (t, n) threshold semiquantum secret sharing protocol is proposed. In the improvement scheme, each receiver can perform the eavesdropping check by measuring the Z-basis sample states. The improved protocol not only has semi-quantum properties but also can repair the security hole of the old version and has enhanced security against various quantum attacks. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the Schwarzschild metric and extend it to the Kruskal-type metric to explore the interior structure of black holes and white holes within the framework of canonical quantum gravity. We applied a canonical quantization procedure to examine the key features of these objects, focusing on the quantization of the event horizon and continuous extension of the Schwarzschild metric to study white holes using the De Broglie–Bohm interpretation approach. Our findings demonstrate that the horizon of the black hole becomes quantized, leading to the disappearance of central singularity. Furthermore, by extending the Schwarzschild metric into a Kruskal–Schwarschild form, we were able to analyze both black and white holes within a unified approach. Through this quantization process, we derive a regular and effective spacetime model for a white hole, which eliminates singularities and provides new insights into the quantum characteristics of black and white holes. [ABSTRACT FROM AUTHOR]

Secure multi-party computation (SMC) enables multiple parties to collaboratively perform computational tasks without revealing their private data. A specific application scenario within SMC is Private Set Intersection with Correlated Sum (PSI-CS), where two participating parties compute the sum of associated elements in their intersection while preserving the privacy of their individual sets. This problem arises in various contexts, including calculating conversion amounts between suppliers and platforms, such as advertising conversion amounts and agency business conversion amounts. The paper proposes a protocol that employs quantum single-photon technology to compute the PSI-CS, provides four technical solutions suitable for various scenarios ranging from small to large data volumes, sparse to dense datasets, and without revealing the cardinality of the intersection. Additionally, the method extends to computing the union set with correlated sums. We experimentally validate the proposed protocol, conduct correctness and security analyses, and demonstrate its practical significance and application value. By utilizing single-photon technology, quantum gate operations, and measurements become more accessible, simplifying the protocol's implementation. Notably, our approach provides unconditional security against quantum computational attacks, representing a substantial improvement in both efficiency and practical applicability compared to classical domain protocols. [ABSTRACT FROM AUTHOR]

In this paper, we study the influence of analytical regularization used in the generalized function (distribution) space to the Tikhonov regularization procedure utilized in the different versions of Moore–Penrose's inversion. By introducing a new analytical term to the Tikhonov regularization of Moore–Penrose's inversion procedure, we derive new optimization conditions that extend the Tikhonov regularization framework and influence the fitting parameter. This enhancement yields a more robust and accurate reconstruction of physical quantities, demonstrating its potential impact on various studies. We illustrate the significance of new term through schematic examples of physical applications, highlighting its relevance to diverse fields. Our findings provide a valuable tool for improving inversion methods and their applications in physics and beyond. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a family of correlation measures relative to a local channel in terms of the metric-adjusted skew information for a global state and reveal their fundamental properties. We quantify the correlation of quantum states with respect to several typical channels, including unitary channels, twirling channels, and weak measurements, and illustrate that the correlation with respect to the twirling channel induced by the fully unitary group is consistent with that relative to the completely depolarizing channel. In particular, we further evaluate the correlations of the Bell diagonal states, Werner states, and isotropic states and make a comparative study for this family of correlation measures with different operator monotone functions of the two-qubit Werner states and isotropic states, respectively. [ABSTRACT FROM AUTHOR]

Due to the non-commutativity of fundamental operators of quantum mechanics, the classical computer can do nothing with operation of quantum gates, in this paper, we propose operator-orderization programme, so that using classical computers we can derive quantum unitary gates from the corresponding classical transformation, as examples, we employ operator-orderization programme to derive Squeezing gate, Not gate, Swap gate and Hadamard gate on classical computers. We predict that our this scheme may have profound applications in the near future. [ABSTRACT FROM AUTHOR]

This study progresses to a detailed analysis of three-dimensional vector fields, focusing on the differential geometric properties of vector lines, including curvature and torsion, using anholonomic coordinates. Further, it investigates the curl of the binormal vector field in specific configurations, leading to the identification of surfaces with both t congruence and b congruence, supported by the Gauss–Mainardi–Codazzi equations under zero abnormality conditions. This paper also examines the application of the Landau–Lifshitz equation to null Cartan curves, deriving the evolution equation for the Spin vector and exploring its implications for moving null Cartan curves. This study attempts to increase understanding of vector field geometry and its various applications by combining theoretical insights with practical techniques. [ABSTRACT FROM AUTHOR]

In this paper, we study the 2-flavor equation of state of the quantum chromodynamics at zero temperature and finite chemical potentials with a modified Nambu–Jona–Lasinio model, where the beta equilibrium and electric charge neutrality conditions of the system (including u, d quarks, electrons and muons) are considered. The related chiral phase transition is also discussed in this paper. For comparison, we show the results with four different parameter sets, and find only quantitative differences. As chemical potential increases, the crossover instead of first-order chiral phase transition happens. Finally, we calculate the binding energy per baryon for different parameter sets, and find that the 2-flavor quark system with a smaller G 1 (or a larger m) possesses the lower binding energy per baryon, indicated to be more stable than the other case. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the generalized Einstein–Maxwell–Dilaton gravity theory with a nonminimal coupling between the Maxwell field and scalar field. Considering different geometric properties of black hole horizon structure, the charged dilaton Lifshitz black hole solutions are presented in 4-dimensional spacetimes. Later, utilizing the Wald Formalism, we derive the thermodynamic first law of black hole and conserved quantities. According to the relationship between the heat capacity and the local stability of black hole, we study the stability of charged Lifshitz black holes and identify the thermodynamic stable region of black holes that meet the criteria. [ABSTRACT FROM AUTHOR]

In this paper, we considered four observationally constrained, one-parameter dark energy models to see their plausible impacts on the tidal ellipticity and related statistics of cosmic voids. Our main question is to see if different models of dark energy could be distinguished through ellipticity of cosmic voids. In this way, we employed an analytic method on the base of local tidal tensor. In this method, the center of a void is located at local minimum of the linear density field. At first, we obtained the effect of the one-parameter DE models on the distribution function of the cosmic voids and simultaneously compared the results with the standard cosmology (Λ CDM). We found that the distribution function of these models is different with respect to that of Λ CDM. In addition, we obtained the mean ellipticity of cosmic voids, 〈 ε 〉 , against redshift and found that in all models the 〈 ε 〉 as well as ε max has a decaying trend. Besides, we considered the mean ellipticity evolution versus the smoothing scale of voids ( R L ). We found that the differences between dark energy models are significantly discernible via the ellipticity evolution versus the void scale ( R L ). We saw that the studied models result in different ellipticity evolutions (versus R L ) up to 5 % smaller with respect to that of the Λ CDM. [ABSTRACT FROM AUTHOR]

This paper delves into the impact of electromagnetic fields on isotropic spherical charged gravastar (CGS) systems within the framework of f (R , Σ , T) gravity. The investigation focuses on singularity-free exact systems of relativistic spheres with a specific equation of state (EoS), employing a suitable choice of the effective field for different regions of the gravastar. The exterior region considers the Reissner–Nordström spacetime, while the interior charged manifold is matched at the junction interface. By utilizing graphical representations, the study examines various physical characteristics of the spherical gravastar system in the presence of an electromagnetic field. The findings reveal that the electric charge plays a significant role in shaping the optimal length, energy content, entropy, EoS parameter of the stellar system, and the energy conditions of our system. Additionally, the stability of the system is also investigated. Here are some of the results obtained. It is determined that both the matter density and pressure remain constant within the interior region of the CGS. The EoS is always negative. Also, the energy conditions are violated in our cosmological system. [ABSTRACT FROM AUTHOR]

In this paper, we present an exact spherically symmetric and Yang–Mills charged AdS black hole solution in the context of 4 D Einstein–Gauss–Bonnet (EGB) gravity in the presence of a cloud of strings. The regularity of the solution is checked. Thermodynamics of this solution is studied. The critical behavior, the types of phase transitions in canonical ensemble, the Joule–Thomson expansion, the Clapeyron equation and the critical exponents shall be investigated. [ABSTRACT FROM AUTHOR]

The connection between quantum entanglement and quantum refrigerators is an active area in quantum thermodynamics. Ongoing investigations are exploring how entanglement in the working medium of a quantum refrigerator can impact its performance. The paper focuses on a two-qubit Heisenberg XXZ spin- 1 2 system featuring Kaplan–Shekhtman–Entin-Wohlman–Aharony (KSEA) and Dzyaloshinsky–Moriya (DM) spin–orbit exchange interactions as the operational physical matter medium for a quantum refrigerator. We provide explicit formulations for relevant thermodynamic quantities of the quantum refrigerator, dependent on the magnetic field (B) and the strengths parameters of spin–orbit interactions. The study explores the relationship between entanglement and thermodynamic properties, using concurrence as a quantitative metric of thermal entanglement. The results emphasize the significant impact of fine-tuning the amplitudes of both DM and K S E A strengths on improving the quantum refrigerator's performance. Finally, the findings suggest that entanglement between the qubits is superfluous for enhancing the quantum refrigerator's efficiency. [ABSTRACT FROM AUTHOR]

In this paper, we study the quantum-corrected Schwarzschild AdS black hole surrounded by quintessence matter in two folds: its thermal quantities and shadows. For this purpose, first, we present a detailed analysis of the influences of the quintessence matter field on Hawking temperature, mass, Gibbs free energy, and specific heat functions. Then, we examine the shadows by following Carter's approach. We find that the shadow radius value takes smaller values for greater quintessence state parameter values. On the other hand, we see that the shadow radius takes greater values for greater values of the normalization parameter. Finally, in a brief section, we discuss the energy emission rate and show that the Gaussian-type plots' peak values are also affected by the quintessence matter field parameters. [ABSTRACT FROM AUTHOR]

In this paper, we study the dissipative dynamics of interferometric power as a discord-like measure in Markovian environments such as dephasing, depolarizing, and generalized amplitude damping. Moreover, we compare the dynamics of interferometric power and entanglement by choosing the proper initial conditions. Our study shows that interferometric power decays asymptotically in all cases where the sudden death of entanglement appears. Therefore, quantum metrology based on interferometric power is more robust than entanglement. [ABSTRACT FROM AUTHOR]

In this paper, within the three-dimensional non-relativistic non-commutative phase–space (3D-NR(NCPS)) symmetries, we examined the 3D deformed Schrödinger equation (3D-DSE) using the improved Coshine Yukawa potential (ICYP) model composed from Coshine Yukawa potential (CYP) (− 4 d e a r exp (− α r) cosh (α r)) and other terms produced from the effect of phase–space deformation ( a d e r 3 L. Θ + 2 d e a α exp (− 2 α r) r 2 L. Θ and d e a exp (− 2 α r) r 3 L. Θ). For this study, the 3D-DSE in the 3D-NR(NCPS) symmetry is solved and discussed with standard independent time perturbation theory and the generalized Bopp's shifts method. For the homogeneous (H2 and N2) and heterogeneous (LiH, ScH, and HCL) diatomic molecules, it is obtained that the improved non-relativistic energy equation and eigenfunction for the ICYP in the presence of deformation phase–space are dependent on the discrete atomic quantum numbers (j , l , s ,m), the dissociation energy d e , the equilibrium bond length the screening parameter r e , the deformation phase parameters (η , χ ¯ , ζ ¯) and the deformation space parameters (Φ , χ , ζ). Additionally, the thermal properties of the CYP and ICYP with 3D Schrödinger equation (3D-SE) and 3D-DSE are thoroughly examined in the three-dimensional non-relativistic quantum mechanics (3D-NR(QM)) known in the literature symmetry and 3D-NR(NCPS) symmetries, including the partition function, mean energy, free energy, specific heat, and entropy. Furthermore, we discussed particular cases of thermodynamic characteristics for the ICYP model. In our study, we have shown that all the physical values related to energy and thermodynamic properties within the framework of the 3D(NR)NCPS symmetry are equal to the corresponding values within the framework of 3D-NR(QM) symmetry known in the literature, in addition to minor effects resulting from their interaction with the topological properties of the deformed phase–space. This study has multiple applications in various domains, including atomic and molecular physics. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the non-relativistic limit of the Dirac equation for relativistic spin-1/2 particles within the framework of the conformable fractional derivative (CFD) using the Foldy–Wouthuysen (FW) transformation. This approach leads to the derivation of a conformable fractional Schrödinger–Pauli equation. We propose and employ a conformable fractional version of the FW transformation, thoroughly examining its efficacy and behavior in the non-relativistic limit. Additionally, based on perturbation theory, we compute the energy shifts within the context of CFD and derive a conformable fractional fine structure of the hydrogen spectrum. [ABSTRACT FROM AUTHOR]

This paper is related to the dynamics of stellar structure under the influence of modified gravity (in particular f (T) gravity, where T is associated with a torsion scalar). We contemplate non-static plane geometry equipped with fluid dissipation in the form of diffusion limit. The suitable variables to handle the analysis are explored. To comprehend the dynamics of the system, we acquire the dynamical equations with the aid of Bianchi identities. We calculate the Taub mass for our structure and develop the relations of mass in the form of collapsing velocity, derivative of proper radial, and time. The scalars to comprehend the evolution and structure are explored for non-static plane geometry. These scalars have a novel existence for this structure. We find that the homogeneous expansion and homologous ways of evolution interrelate with each other. We perform the investigation for two cases that is dissipative and non-dissipative. The nature of the fluid in the dissipative case is shear and geodesic. We calculate the variety of solutions in this case. The analysis is concluded by analyzing the stability of the vanishing Y TF constraint. [ABSTRACT FROM AUTHOR]

In this paper, we deal with spacetimes allowing a semi-symmetric connection whose metric tensor is recurrent. We investigate the impact of this connection on spacetimes and establish a nontrivial example. We physically explain the properties of spacetime that we obtained. Under a certain condition, we demostrate that a spacetime admitting such a connection becomes the GRW spacetime as well as the anti-de Sitter and represents the dark matter era. Finally, we scrutinize in case such a spacetime admits a Ricci soliton and generalized Ricci soliton. [ABSTRACT FROM AUTHOR]

The bound state solutions of the Schrödinger equation (SE) under a deformed hyperbolic potential are used in this paper to investigate the correlation between the information content, such as Shannon entropies and Fisher information, and the variance of a quantum system in both momentum and position spaces. The variance was obtained from the expectation moments in conjugated spaces and used to get the uncertainty products, Fisher information products and Shannon entropic sums for different potential parameters. These information measures were observed to vary with the potential parameters and obey their lowest bound inequalities. An increase in the Fisher information leads to a lower uncertainty and less information while decreases in the Fisher information result in higher uncertainties. We proposed a relationship between the Shannon entropies, Fisher information and the variance where an increase in the Fisher information leads to a lower Shannon entropy or a lower spread of the probability distribution and vice versa. The numerical results obtained with the proposed relations agree with the most utilized method in the literature. This current work simplifies the calculation of the Shannon entropies notably for complex potential functions. [ABSTRACT FROM AUTHOR]

In this paper, we extend the self-consistent quasi-particle model proposed by Zong et al. [Phys. Lett. B 711, 65 (2012)] to the case of finite magnetic field. The vacuum infinity zero-point energy is successfully eliminated by introducing a classical thermo-magnetic background field B (T , e B) in the effective Lagrangian based on Zong's method. By considering relativistic Landau energy levels, we have applied the improved quasi-particle model to the case of a two-flavor quark gluon plasma. We obtain a finite partition function and calculate the energy density, pressure and entropy density at zero chemical potential. These results are qualitatively consistent with the results of previous literature works. [ABSTRACT FROM AUTHOR]

In this paper, we propose a nonlocal extension of the mimetic dark matter model based on the FALVA implementation of fractional calculus. Our primary objective to explore how certain properties of dark matter can be modeled within the FALVA framework rather than formulate a phenomenological model. We begin by constructing the action functional of the cosmological extension of the mimetic dark model and deriving the nonlinear equations of motion in the general case. Next, we focus on a fractional-power homogeneous mimetic dark field with an exponential expansion factor. We derive the equation of motion for the lapse field and obtain its general solution. Analytical solutions are then obtained for small time intervals and arbitrary values of the fractionality parameter. These solutions enable us to establish the physical line element of spacetime, incorporating the mimetic dark matter field. From this line element, we derive the Ricci tensor, Ricci scalar, and geodesic equations. [ABSTRACT FROM AUTHOR]

In this paper, we show that loop-induced processes involving new physics particles can readily satisfy Landau Equation and trigger triangular singularities at high-energy colliders, leading to fully visible Standard Model final states. In addition, a t-channel triangular singularity can also occur during particle scattering processes that may extend to low momentum exchange. We discuss several typical scenarios in supersymmetric and extended Higgs models, and three types of final-state kinematic features at the collider. Four-particle vertices in new physics can play a significant role in high energy diagrams. We identify an "everything on shell" triangular singularity diagram only involving bosonic couplings, which has the potential to completely avoid large virtuality suppression. We further show that such a virtuality-free diagram is missing in the Standard Model at electroweak scale, and it becomes available in new physics models. [ABSTRACT FROM AUTHOR]

This paper examines the behavior of the universe around the bouncing point in the background of f (,) theory, where is the non-metricity and is the trace of the energy–momentum tensor. We derive the field equations that describe gravitational phenomena in the existence of non-metricity and matter source terms. By applying the reconstruction method for the Hubble parameter, a phenomenon of the bouncing universe for homogeneous spacetime filled with perfect fluid is studied. We consider specific models of this modified theory to evaluate the behavior of various cosmic parameters such as the Hubble, deceleration, equation of state and fluid parameters. When the null energy condition is violated, it follows a bouncing behavior. It is found that spacetime is composed of isotropic fluid, where a big bounce can occur and the universe turns into extremely unstable. We conclude that f (,) gravity successfully explains the early and late time cosmic expansion and evolution. [ABSTRACT FROM AUTHOR]

In this paper, we explore the impact of Barrow's entropy on the topological classification of d-dimensional black holes (BHs). Specifically, we examine the Gauss–Bonnet (GB) and singly rotating Kerr black holes (KBHs) as well as their AdS counterparts. We notice that Barrow's entropy significantly influences the topological numbers of these BHs. To understand these effects, we use the thermodynamic domain — the space defined by thermodynamic variables like temperature and pressure — to study topologically inspired defects in the BHs. These defects are points in the thermodynamic domain where singular or discontinuous behavior occurs. By computing the winding numbers of these defects, which are integers that count how many times a loop around the defect encircles the origin, we can understand the local and global topology of the BHs. Our analysis suggest that the topological number () derived from Barrow's statistics differs from the one obtained using Gibbs–Boltzmann statistics. Furthermore, we observe that BHs can undergo topological phase transitions that characterize them in different thermodynamic topological classes. Overall, these findings demonstrate the importance of Barrow's entropy in understanding the topological classification of BHs, and highlight the potential for further research in this area. [ABSTRACT FROM AUTHOR]

We manipulated and adjusted the absorption, dispersion, group index, and group velocity in a sodium atomic medium by controlling the strength and collective phase of the driving fields. The group index in these regions is calculated to be − 250,000. The group velocity v g in these locations is measured to be − 0. 1 2 × 1 0 − 4 m/s. An investigation is conducted on a negative delay of − 5 0 μ s in the sodium medium. The presence of negative delay and negative group velocity indicates the occurrence of superluminal propagation of light pulses within the medium. The negative group index is increased from − 1 × 1 0 5 to − 4 × 1 0 5 , and the negative delay time is increased from − 2 0 μ s to − 7 0 μ s, with the driving field E 2 having a Rabi frequency. The work presented in this paper has substantial implications for the fields of gravitational wave detection, radar technology, and temporal cloaks. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the effect of a circularly polarized laser field on the inverse muon decay process (e − ν μ → ν e μ −) in electroweak theory with the exchange of a boson vector W − . Our method accounts for the dressing of incident electron and scattered muon by introducing the first-order laser-matter interaction of perturbation theory and using the relativistic Dirac–Volkov formalism. We have analyzed the behavior of the total cross-section (TCS) with charged-current as a function of the center-of-mass energy and the laser field parameters, such as the number of photons exchanged, the laser field strength and frequency. We have found that the circularly polarized laser field significantly affects the inverse muon decay process by reducing the TCS. We have also shown that the photonic energy transfer envelopes are perfectly symmetric with respect to the number of photons exchanged and rapidly drop when the indices of the Bessel functions are close to their arguments. [ABSTRACT FROM AUTHOR]

Gravitational waves result from various spacetime-perturbing events which are due to various kinds of motions and changing distributions of mass. Most studies on the source of gravitational waves were derived from the dynamic character of two binary compacted massive objects such as black holes and neutron stars, therefore gravitational waves which originated from a single event source would be of interest. In this paper, we derive the stress–energy tensor (SET) of a braneworld wormhole and demonstrate how the bulk-induced gravitational waves influence the SET of the wormhole. Thus, this study not only suggests a single source of gravitational waves, but also proves the existence of higher dimensional space by providing a formulation, namely, the SET at the wormhole throat affected by the bulk-induced gravitational waves. [ABSTRACT FROM AUTHOR]

This paper provides a summary of the fractal calculus framework. It presents higher-order homogeneous and nonhomogeneous linear fractal differential equations with α -order. Solutions for these equations with constant coefficients are obtained through the method of variation of parameters and the method of undetermined coefficients. The solution space for higher α -order linear fractal differential equations is defined, showcasing its non-integer dimensionality. The solutions to α -order linear fractal differential equations are graphically depicted to illustrate their non-differentiability. Additionally, equations of motion governing the behavior of two masses in fractal time are proposed and solved. [ABSTRACT FROM AUTHOR]

This study explores the cosmological constant problem and modified uncertainty principle within a unified framework inspired by a void-dominated scenario for cosmology. In a recent paper [E. Yusofi, M. Khanpour, B. Khanpour, M. A. Ramzanpour and M. Mohsenzadeh, Mon. Not. R. Astron. Soc. 511, L82 (2022)], voids were modeled as spherical bubbles of similar average sizes, and the surface energy on the voids' borders was calculated across various scales in a heuristic manner. We show that these result in a significant discrepancy of approximately (+ 1 2 2) between the cosmological constant values from the minimum to the maximum radii of bubbles. Furthermore, when considering the generalized form of the uncertainty principle with both minimum and maximum lengths, i.e. Δ X Δ P ≥ ℏ 2 1 1 − β Δ P 2 1 1 − α Δ X 2 , a similar order of discrepancy is observed between α max and α min , indicating that α ∝ β − 1 ∝ Λ ∝ length − 2 (m − 2). As a primary outcome of this finding, we offer a novel uncertainty principle that incorporates a nonzero cosmological constant. [ABSTRACT FROM AUTHOR]

In this paper, we present a model of inflation in the original form of Brans–Dicke (BD) theory without any modification and without adding any dark energy candidate. We consider a log function of the scale factor in the BD scalar field to discuss the inflationary era of the universe. We obtain the expressions for the deceleration parameter and the equation of state parameter, and plot their graphs against the cosmic scale factor. We observe that the universe starts with decelerated expansion and experiences an early time phase transition from a decelerated phase to an accelerated phase. After a very short period, the accelerated expansion ends in a decelerated expansion, showing the inflationary era of the cosmic evolution. To analyze the model on thermodynamic ground, we consider generalized second law of thermodynamics and observe that the law is satisfied within the model. Further, we study the stability of the model using the squared sound speed method. We plot the squared sound speed against cosmic time t and discuss the effects of the parameters on the stability of the model. We observe that for suitable values of the model parameters our model is stable. [ABSTRACT FROM AUTHOR]

This paper investigates the static spherically symmetric vacuum solutions of Brans–Dicke Theory of Gravity. In this paper, we systematically derive the static spherically symmetric solutions by starting with the general static spherically symmetric anzats, discovering the nonzero Christoffel symbols, nonzero Ricci tensor components and the Ricci Scalar. These results allow us to rewrite the four Brans–Dicke gravitational field equations explicitly in terms of the metric components, the scalar field and its scalar potential. This paper systematically explains and shows how to modify these linear second-order ordinary differential equations in order to be able to find the solution of the scalar field, the metric components and the scalar potential analytically. We successfully find the most general solution of the static spherically symmetric vacuum solutions of Brans–Dicke gravity and the well-known Schwarzschild solution is recovered as the simplest solution. [ABSTRACT FROM AUTHOR]

Lots of ready quantum private comparison (QPC) protocols usually only judge whether two users' data are equal, whereas the quantum private magnitude comparison (QPMC) protocol can compare the magnitude of two numbers, whose results are greater than, equal and less than. It is by announcing a comparison result of two bits in two data that the existent QPMC protocols determine the size relationships of the whole data. Although the announcement leaks no information to outside attackers, yet it alerts two participants to know each other's value of a certain bit. This is termed as bit leakage in this paper. In order to remedy this shortage, the paper proposes a novel QPMC protocol using a type of Bell state. The protocol is thoroughly analyzed, correct and secure. Also, it proves free of bit leakage. Additionally, because it is easier to implement because of the usage of a type of Bell state, it counts as a better alternative for QPMC. [ABSTRACT FROM AUTHOR]

The possibility of the existence of multiquark hadrons made of 4-quarks for mesons and 5-quarks for baryons was predicted by Gell-Mann [Phys. Lett. 8, 214 (1964)]. The renewed interest for the search for exotic pentaquark states was initiated by the paper by Diakonov, Petrov, and Polyakov [Z. Phys. A 359, 305 (1997)]. The 2003 experimental reports on the observation of Θ + pentaquark with u u d d s ̄ quark content created a great excitement and many following experiments have reported its observation [K. H. Hicks, Eur. Phys. J. H 37, 1 (2012)]. After high-statistics experiments at JLab, which did not confirm previous claims by the CLAS collaboration, the community concluded that the Θ + pentaquark either does not exist at all or has an extremely small cross-section, making it currently unobserved. There were different review papers on this subject, questioning the existence of Θ + or trying to explain the reasons why reaching a conclusion based on production experiments is challenging [M. Amaryan, Eur. Phys. J. Plus 137, 684 (2022)]. To address the challenge of minimal 3-body final states, a formation experiment with a projectile-kaon beam is proposed. In the following, we discuss how the Θ + could be observed in the K L p → Θ + → K + n reaction in the KLF experiment at JLab [M. Amaryan et al. [KLF Collaboration], arXiv:2008.08215 [nucl-ex]]. [ABSTRACT FROM AUTHOR]

In this paper, we calculate the vacuum energy as a functional from the phion propagator in 4D model of complex scalar field (phion) which interacts with a real matrix scalar field (chion). The condition of stationarity of this functional gives us the equation for phion propagator. At some critical value of the coupling, the propagator changes its asymptotic behavior in the deep-Euclidean region of momenta. This behavior corresponds to some critical phenomenon. The study of the convexity of the energy functional shows that the solution obtained actually corresponds to the theory. We also discuss the stabilization of the ground state in the strong-coupling region by effective self-action of phions. [ABSTRACT FROM AUTHOR]

In this paper, we construct a Schwarzschild metric in the fractal dimension based on fractal calculus, and we study the deflection of light near the sun. It was observed that the new fractal spherically symmetric spacetime metric may describe supermassive black holes, which have been detected through various astronomical observations such as SDSS. We have discussed the deflection of light by the gravitational field of the sun. It was observed that the total deflection of light is affected by the fractal dimension. To estimate the numerical value of the fractal dimension, we have used the 2004 analysis of almost 2 million VLBI observations of 541 radio sources made by 87 VLBI sites, which estimates the factor γ based on PNN formalism. It was observed that the fractal dimension is roughly less than unity. However, our analysis showed that large bending gravity gives fractal dimensions lower than unity to some extent. We also gave a naïve idea about the emission thermal Unruh process in fractal dimension. It was observed that both the temperature and the entropy of black holes are affected by the fractal dimension, and that for low numerical values, the entropy of the black hole is enhanced. [ABSTRACT FROM AUTHOR]

In this paper, we involve the galactic halo observational data to test the weak field General Relativity involving the cosmological constant. By using the data for 15 hydrogen (Hi) VLA super spirals and the Tully–Fisher relation, we obtain constraints for each galaxy. The results are consistent with previous results for spiral galaxies, as well as with the scaling relations for the halos, thus confirming the efficiency of the use of dark halo data and Tully–Fisher relation, including the baryonic Tully–Fisher index (BTFR), for testing modified gravity models. [ABSTRACT FROM AUTHOR]

Axion-like particles (ALPs), which are pseudo-scalar particles, appear in various new physics models with the spontaneous global symmetry breaking. The difference between ALPs and axion models is that for the former both masses and couplings of ALPs are free parameters. It appears that the ALPs with masses above 1 GeV are beyond the reach of low-energy accelerators, existing cosmological and astrophysical constraints, while high-energy colliders provide unique possibilities to explore such particles. With the establishment of the International Muon Collider Collaboration, muon colliders have been widely concerned. In general, ALPs are mainly produced at muon colliders through the μ + μ − annihilation and electroweak vector-boson-fusion (VBF) processes. In this paper, we study the prospect of the production of heavy ALPs with mass greater than 10 GeV via the massless γ γ -fusion process at the multi-TeV muon collider. Focusing on the couplings of ALPs to the Standard Model gauge bosons, we obtain the excluding and discovering capabilities for ALPs at the 3 TeV and 10 TeV muon colliders. Our numerical results suggest that the multi-TeV muon collider may be more sensitive to ALPs with the mass of 35–400 GeV than LHC, and can provide the possibility to search for ALPs with masses greater than 3 TeV. In addition, we also discuss the effect of narrow width approximation on the ALP search sensitivity. [ABSTRACT FROM AUTHOR]

In this paper, we study the quantum Chicken game under fluctuating massless scalar field subjected to a reflecting boundary. The noisy scheme of quantum Chicken game affected by fluctuating scalar field is constructed. Then we analyze the influences of vacuum fluctuation, two-atom separation and boundary on the game payoff and Nash equilibrium. It is shown that for different strategy profiles, vacuum fluctuation, two-atom distance and atom-boundary distance have different influences on game payoffs. Vacuum fluctuation and two-atom distance may produce positive or negative effects on game payoffs dependent on the specific strategies. It is found that boundary can effectively promote the game payoffs corresponding to those strategy profiles with which payoffs are degraded by vacuum fluctuation. Furthermore, Nash equilibrium of the game is broken under the influence of fluctuating quantum field, but the game symmetry does not change. For long-time evolution, ( D ̂ , Ĉ) and (Ĉ , D ̂ ) turn into new Nash equilibria. The results would be helpful for understanding and conducting quantum Chicken game in an open quantum system. [ABSTRACT FROM AUTHOR]

In this paper, we apply quantum cosmology to investigate the early moments of a Friedmann–Lemaître–Robertson–Walker (FLRW) cosmological model, using Hořava–Lifshitz (HL) as the gravitational theory. The matter content of the model is a dust perfect fluid. We start studying the classical model. Then, we write the total Hamiltonian of the model, quantize it and find the appropriate Wheeler–DeWitt equation. In order to avoid factor ordering ambiguities, in the Wheeler–DeWitt equation, we introduce a canonical transformation. We solve that equation using the Wentzel–Kramers–Brillouin (WKB) approximation and compute the tunneling probabilities for the birth of that universe (T P WKB ). Since the WKB wave function depends on the dust energy and the free coupling constants coming from the HL theory, we compute the behavior of TP WKB as a function of all these quantities. [ABSTRACT FROM AUTHOR]

In this paper, we consider an exponential potential V (ϕ) = V 0 e − α ϕ in the framework of Barrow entropy under the constant-roll inflation and check their viability in the light of observable Planck 2020 data. By applying the first law of thermodynamics to the apparent horizon of the Universe, a modification of the Friedmann–Robertson–Walker (FRW) metric is derived in the context of Barrow entropy. We consider the early inflationary period of the universe to consist phenomenologically of a single inflationary state, that is, a state of the costant-roll inflation in which inflation is driven by an exponential potential field function. By fitting the constant-roll inflationary models to the observations, we examined the effect of the Barrow parameter Δ on the inflation mechanism with the constant-roll parameter γ. As a result, we concluded that for a viable inflation, the observation limits of the inflation parameters determine that the constant-roll parameter is in the range 0. 0 1 1 ≤ γ ≤ 0. 0 1 6. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the anisotropic and spatially homogeneous Bianchi type-I universe with Kaniadakis holographic dark energy in Saez–Ballester [Phys. Lett. A 113, 467 (1986)] theory of gravitation. We determine Kaniadakis holographic dark energy model by assuming a correlation between the metric potentials to solve the field equations of the model. This results in a dynamical deceleration parameter which demonstrates an accelerating expansion of the universe. Our model's equation of state parameter ω khde close to − 1 (Λ CDM model) at late-times and is in agreement with the most recent observations. Next, we obtained the squared sound speed ( v s 2 ) and found that it is positive, implying stability against perturbations. The ω khde − ω khde ′ plane is constructed to investigate the evolution of the models' EoS parameter turned out to be in a freezing zone. As should be the case in an expanding universe, the strong energy conditions of the model are violated. Statefinders (r , s) , and r − q planes were also examined. Our model includes the Chaplygin gas, Λ CDM limit, and is inclined towards the steady-state model. [ABSTRACT FROM AUTHOR]

This paper presents an analytical solution for the Milburn equation describing the interaction between a 3-level atom in a Ξ -configuration, a cavity field, and a nonlinear Kerr-like medium. The Hamiltonian of the model is presented in the rotating wave approximation (RWA) under specific conditions. The obtained analytical solution accounts for the impact of intrinsic decoherence and nonlinear terms on the dynamics of various physical phenomena. Specifically, we explore the behavior of atomic population, entropy functions, entanglement, negativity, and correlation, highlighting their dependence on the physical parameters of the 3 -level atom-cavity system. [ABSTRACT FROM AUTHOR]

In this paper, we utilize the effective Lagrangian method within the tree-level Born approximation to explore ϕ -meson photoproduction, i.e. γ p → ϕ p. Our analysis encompasses contributions from various sources, including the Pomeron, f 1 -Regge, pseudoscalar particles (π , η), scalar particles ( a 0 , f 0 ), protons, and three-nucleon resonance states. In addition, we consider a possible pentaquark-like K ∗ Σ -bound state P s . The findings indicate that, apart from the region near the threshold, contributions other than the Pomeron generally have a limited impact on the total cross-section. However, alternative contributions become crucial at specific angles, particularly at smaller values of cos θ. The incorporation of P s and other nucleon resonances proves essential to elucidate the bump observed near W ∼ 2. 1 5 GeV at very forward angles and behaviors within the range of W = (2. 0 − 2. 3) GeV. Furthermore, in the region with W ≥ 2. 5 GeV, where nucleon resonances become negligible, contributions from the t-channel mesons become pivotal. Our calculations for spin density matrix components, examined in various frames, exhibit improvement when considering all contributions. This comprehensive approach successfully reproduces the observed bump by including P s . We also briefly estimate the P s production via ϕ -meson photoproduction in the future Electron-Ion Collider (EIC), resulting in the luminosity of 10 fb − 1 per month. [ABSTRACT FROM AUTHOR]

In [Phys. Rev. D 107, 104008 (2023)], we reported a novel exact closed-form solution which describes asymptotically flat spacetimes in pure ℛ 2 gravity. The solution is Ricci scalar flat, viz. ℛ ≡ 0 everywhere. Whereas any metric with a null Ricci scalar would trivially satisfy the ℛ 2 vacuo field equation, ℛ (ℛ μ ν − 1 4 g μ ν ℛ) + g μ ν □ ℛ − ∇ μ ∇ ν ℛ = 0 , in this paper, we shall show that our solution satisfies a "stronger" version of the ℛ 2 vacuo field equation, viz. ℛ μ ν − 1 4 g μ ν ℛ + ℛ − 1 (g μ ν □ ℛ − ∇ μ ∇ ν ℛ) = 0 , despite the term ℛ − 1 being singular. Even though ℛ identically vanishes, for our solution, the combinations ℛ − 1 ∇ μ ∇ ν ℛ and ℛ − 1 □ ℛ are free of singularity. This exceptional property sets our solution apart from the set of null-Ricci-scalar metrics and makes it a genuinely nontrivial solution. We further demonstrate that, as a member of a larger class of asymptotically de Sitter metrics, our solution is resilient against perturbations in the scalar curvature at largest distances, making it relevant for physical situations where the background deviates from asymptotic flatness. [ABSTRACT FROM AUTHOR]