Graph surfaces invariant by parabolic screw motions with constant curvature in H²×R

In this work we study vertical graph surfaces invariant by parabolic screw motions with pitch ℓ > 0 and constant Gaussian curvature or constant extrinsic curvature in the product space H² × R. In particular, we determine flat and extrinsically flat graph surfaces in H² × R. We also obtain complete and non-complete vertical graph surfaces in H² × R with negative constant Gaussian curvature and zero extrinsic curvature.Publisher's VersionQ4WOS:00098579570001

Pseudo-spherical submanifolds with 1-type pseudo-spherical Gauss map

In this work, we study the pseudo-Riemannian submanifolds of a pseudo-sphere with 1-type pseudo-spherical Gauss map. First, we classify the Lorentzian surfaces in a 4-dimensional pseudo-sphere $\mathbb{S}^4_s(1)$ with index s, $s=1, 2$, and having harmonic pseudo-spherical Gauss map. Then we give a characterization theorem for pseudo-Riemannian submanifolds of a pseudo-sphere $\mathbb{S}^{m-1}_s(1)\subset\mathbb{E}^m_s$ with 1-type pseudo-spherical Gauss map, and we classify spacelike surfaces and Lorentzian surfaces in the de Sitter space $\mathbb{S}^4_1(1)\subset\mathbb{E}^5_1$ with 1-type pseudo-spherical Gauss map. Finally, according to the causal character of the mean curvature vector we obtain the classification of submanifolds of a pseudo-sphere having 1-type pseudo-spherical Gauss map with nonzero constant component in its spectral decomposition

On spherical submanifolds with finite type spherical Gauss map

Chen and Lue (2007) initiated the study of spherical submanifolds with finite type spherical Gauss map. In this paper, we firstly prove that a submanifold Mn of the unit sphere double-struck Sm-1 has non-mass-symmetric 1-type spherical Gauss map if and only if Mn is an open part of a small n-sphere of a totally geodesic (n + 1)-sphere double-struck Sn+1 ⊂ double-struck Sm-1. Then we show that a non-totally umbilical hypersurface M of double-struck Sn+1 with nonzero constant mean curvature in double-struck Sn+1 has mass-symmetric 2-type spherical Gauss map if and only if the scalar curvature curvature of M is constant. Finally, we classify constant mean curvature surfaces in double-struck S3 with mass-symmetric 2-type spherical Gauss map.Publisher's Versio

On submanifolds of pseudo-hyperbolic space with 1-type pseudo-hyperbolic gauss map

In this paper, we examine pseudo-Riemannian submanifolds of a pseudo-hyperbolic space ℍm-1 s (-1) ⊂ Em s+1 with finite type pseudo-hyperbolic Gauss map. We begin by providing a characterization of pseudo-Riemannian sub- manifolds in ℍm-1 s (-1) with 1-type pseudo-hyperbolic Gauss map, and we obtain the classification of maximal surfaces in ℍm-1 2 (-1) ⊂ Em 3 with 1-type pseudo-hyperbolic Gauss map. Then we investigate the submanifolds of ℍm-1 s (-1) with 1-type pseudo-hyperbolic Gauss map containing nonzero constant component in its spectral decomposition.Publisher's Versio

Classification of minimal Lorentzian surfaces in S-2(4) (1) with Constant Gaussian and normal curvatures

In this paper we consider Lorentzian surfaces in the 4-dimensional pseudo Riemannian sphere S-2(4)(1) with index 2 and curvature one. We obtain the complete classification of minimal Lorentzian surfaces S-2(4)(1) whose Gaussian and normal curvatures are constants. We conclude that such surfaces have the Gaussian curvature 1/3 and the absolute value of normal curvature 2/3. We also give some explicit examples.TUBITAK 1001 project Y_EUCL2TIP [114F199]This work was obtained during the TUBITAK 1001 project Y_EUCL2TIP (Project Number: 114F199).Publisher's Versio

A mathematical model for human-to-human transmission of COVID-19: a case study for Turkey’s data

In this study, a mathematical model for simulating the human-to-human transmission of the novel coronavirus disease (COVID-19) is presented for Turkey’s data. For this purpose, the total population is classified into eight epidemiological compartments, including the super-spreaders. The local stability and sensitivity analysis in terms of the model parameters are discussed, and the basic reproduction number, R0, is derived. The system of nonlinear ordinary differential equations is solved by using the Galerkin finite element method in the FEniCS environment. Furthermore, to guide the interested reader in reproducing the results and/or performing their own simulations, a sample solver is provided. Numerical simulations show that the proposed model is quite convenient for Turkey’s data when used with appropriate parameters.No sponso