International Journal of Modern Physics A

In recent years, interesting curved-space extensions of nonrelativistic (NR) string theory have been very actively pursued, where the background has a structure that is a stringy generalization of Newton–Cartan geometry. Here we show that the natural black branes of the NR theory, sourced by the familiar repertoire of stringy objects, generally have a different structure. The black string is our main example. We find that the source distorts the background significantly, generating a large throat within which physics is in fact relativistic. It is only far away from the throat that the background approaches the string Newton–Cartan form. We show that exactly the same is true for the longitudinal RR-charged black brane. On the other hand, the transverse RR-charged black brane turns out to have a proper string Newton–Cartan structure everywhere, not just asymptotically.

This work is based upon classical achievements of S-matrix bootstrap together with an outline of its modern applications. We establish the connection from integral scattering amplitudes to the use of bootstrap technique in modern conformal field theories and holography. Using bootstrap approach, we provide the calculations for integral representations for the sine-Gordon S-matrix elements. Minimal form factors of this model are related to recent studies of certain conformal field theories. We also propose the extension of the sine-Gordon bootstrap equations to the space of conformal correlators known as celestial amplitudes.

This paper deals with the study of quasi-spherical gravitational collapse in the framework of $f(R,T)$ theory. We will divide geometry of the star into two distinct portions i.e. interior portion and exterior portion. In the interior portion, we consider quasi-spherical Szekeres line element and in the exterior portion we take Vaidya line element. The interior and exterior portions will be glued by using Israel’s junction conditions [W. Israel, Il Nuovo Cimento B (1965–1970) 44, 1 (1966); W. Israel, Phys. Lett. A 24, 184 (1967)]. The field equations will be derived in the context of $f(R,T)$ theory for a particular model. Apparent horizons and their time configuration for various desirable cases will also be discussed.

This research study primarily will focus on investigating how the topological effects influence the eigenvalue solutions in the presence of a hot-dense medium. To accomplish this, we employ the non-relativistic Schrödinger wave equation by taking into consideration both the quantum flux field and interaction potential. Through this approach, we determine the energy eigenvalues and their corresponding wave functions using the Nikiforov–Uvarov method. Our findings indicate that when we consider both the topological effects and the magnetic flux, $\mathrm{\Phi }$, there is a noticeable reduction in the binding energy within the hot-dense medium. Additionally, we analyze the role of the baryonic potential in shaping the binding energy within the $(T,u_b)$ plane. Interestingly, it is evident that the influence of the baryonic potential becomes more pronounced as its values decrease.

In this paper, we present our QCD analysis of the Nucleon Form Factors presented by JLab to extract a new parameterization for the valence Generalized Parton Distributions (GPDs), $H_v^q(x,\xi =0,t)$ and $E_v^q(x,\xi =0,t)$. We choose simple parameterizations for $x-$ and $t-$ dependence of GPDs at zero skewness. These free parameters of the model are then obtained using old and new data of nucleon’s elastic electromagnetic form factors (FFs) from JLAB. We have also used the “Hessian method” to perform a careful estimation of the uncertainties for the nucleon GPDs and corresponding observables originate from experimental errors. We also calculate the parton distribution functions (PDFs) in Impact parameter space to show the 3D structure of the Nucleon. We also calculated the proton and the neutron charge densities ${\rho }_{\mathrm{\text{ch}}}^{(p,n)}$. We show that there is a highly localized negative charge near the center of the neutron and it is because of the negatively charged down quarks dominating the high momentum quarks in the neutron. Finally using the obtained Dirac’s FF, we had an estimation for the proton charge radius. The predictions based on the obtained nucleon GPDs are in good agreement with all available experimental data and other phenomenological models.

In this paper, we analyze weak gravitational lensing by taking the black hole solution in Einstein Cubic gravity with the Gibbons and Werner approach. We deduce the deflection angle of light in a nonplasma and plasma medium. Firstly, we derive the Gaussian optical curvature and apply the Gauss–Bonnet theorem to find the deflection angle for the black hole spherically symmetric space–time. Additionally, we examine the graphical behavior of the deflection angle caused by the black hole in the presence of the nonplasma and plasma medium. Further, we use Einstein cubic gravity black hole geometry to discuss the quasi-periodic oscillations, effective force, and emission energy.

This work involves augmenting the $\mathrm{\Delta }(54)$ flavor symmetry model by incorporating two Standard Model Higgs particles into the Inverse Seesaw mechanism. The mass matrices are discussed numerically in the framework of $\mathrm{\Delta }(54)$ flavor for Majorana neutrinos. We introduced Vector-like fermions and Weyl fermions, which are gauge singlets in the Standard Model and produces Majorana mass terms. We restrict the undesirable terms in our Lagrangian by using additional symmetry. Due to these additional terms, the mass matrices deviate from the tribimaximal neutrino mixing pattern, resulting in the production of a nonzero reactor angle ${\theta }_{13}$. We found that the atmospheric oscillation parameter (${\theta }_{23}$) occupies the upper octant under the normal hierarchy situation. We also study the CP violation (${\delta }_{\mathrm{\text{CP}}}$), Jarlskog invariant parameter (J) and Neutrinoless double-beta decay parameter ($m_{ee}$) in the parameter space of the normal hierarchy model to see whether they concur with the most recent neutrino observations.