Scalar-Torsion Theories in Four Dimensional Static Spacetimes

In this paper, we consider a class of static spacetimes scalar-torsion theories in four dimensioanal static spacetimes with the scalar potential turned on. We discover that the 2-dimensional submanifold must admit constant triplet structures, one of which is the torsion scalar. This indicates that these equations of motion can be reduced to a single highly non-linear ordinary differential equation known as the master equation. Then, we show that there are no exact solution of the scalar-torsion theory in four dimensions considering the Sinh-Gordon potential.

METODE ALTERNATIF DALAM MENENTUKAN SOLUSI PARTIKULAR PERSAMAAN EULER-CAUCHY

Euler-Cauchy equation is the typical example of a linear ordinary differential equation with variable coefficients. In this paper, we apply the alternative method to determine the particular solution of Euler-Cauchy nonhomogenous with polynomial and natural logarithm form. An explicit formula of the particular solution is derived from the use of an upper triangular Toeplitz matrix. The study showed that this method could be finding the particular solution for the Euler-Cauchy equation

General Solution Of Nth-Order Linear Ordinary Differential Equation

In this paper we present a solution expression for the general Nth-order linear ordinary differential equation as our main result which involves the use of Integrating Factors where the Integrating Factors are determined using a set of equations such that when this set of equations can be solved, the solution of the concerned differential equation can be determined completely. In this regard we also present result for a special case corresponding to the main result where the solution of the general Nth-order linear ordinary differential equation can be determined completely when N-1 out of N complementary solutions are known.

General Solution Of Nth-Order Linear Ordinary Differential Equation With Constant Coefficients

In this paper we present a formula for the general solution of Nth-order linear ordinary differential equation with constant coefficients as our main result. In this regard we also present two supporting results in this paper which reduce the order of the concerned differential equation by one and give the relation between the coefficients of the initial differential equation and the differential equation obtained. We also discuss about the complementary solution and homogeneous equations with regard to the main result described in this paper.

On the Numerical Simulation of HPDEs Using θ-Weighted Scheme and the Galerkin Method

Herein, an efficient algorithm is proposed to solve a one-dimensional hyperbolic partial differential equation. To reach an approximate solution, we employ the θ-weighted scheme to discretize the time interval into a finite number of time steps. In each step, we have a linear ordinary differential equation. Applying the Galerkin method based on interpolating scaling functions, we can solve this ODE. Therefore, in each time step, the solution can be found as a continuous function. Stability, consistency, and convergence of the proposed method are investigated. Several numerical examples are devoted to show the accuracy and efficiency of the method and guarantee the validity of the stability, consistency, and convergence analysis.

Construction of Green’s functional for a third order ordinary differential equation with general nonlocal conditions and variable principal coefficient

In this work, the solvability of a generally nonlocal problem is investigated for a third order linear ordinary differential equation with variable principal coefficient. A novel adjoint problem and Green’s functional are constructed for a completely nonhomogeneous problem. Several illustrative applications for the theoretical results are provided.

Relative error analysis of matrix exponential approximations for numerical integration

In this paper, we study the relative error in the numerical solution of a linear ordinary differential equation y′(t) = Ay(t), t ≥ 0, where A is a normal matrix. The numerical solution is obtained by using at any step an approximation of the matrix exponential, e.g. a polynomial or a rational approximation. The error of the numerical solution with respect to the exact solution is due to this approximation as well as to a possible perturbation in the initial value. For an unperturbed initial value, we find: 1) unlike the absolute error, the relative error always grows linearly in time; 2) in the long-time, the contributions to the relative error relevant to non-rightmost eigenvalues of A disappear.