Results 11 to 20 of about 4,683,450 (296)
New Anisotropic Exact Solution in Multifield Cosmology
Universe, 2021 In the case of two-scalar field cosmology, and specifically for the Chiral model, we determine an exact solution for the field equations with an anisotropic background space.
Andronikos Paliathanasis
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Physics Letters BAstrophysical black holes come from exact solutions of the Einstein field equations. Therefore, any alternative–such as a gravastar–must meet the same standard of mathematical accuracy and internal consistency.
Farook Rahaman +4 more
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Exact solution of the Susceptible–Infectious–Recovered–Deceased (SIRD) epidemic model [PDF]
Electronic Journal of Qualitative Theory of Differential Equations, 2022 Exact solution of the Susceptible-Infectious-Recovered-Deceased (SIRD) epidemic model is established, and various properties of solution are derived directly from the exact solution.
Norio Yoshida
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On the Exact Solution for the Schrödinger Equation
ParticlesFor almost 75 years, the general solution for the Schrödinger equation was assumed to be generated by an exponential or a time-ordered exponential known as the Dyson series.
Yair Mulian
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Analytical and Numerical Solution of Heat Transfer Equation in Rectangular Composite Fins [PDF]
Mechanics of Advanced Composite Structures, 2022 Today, the use of composites has received widespread attention due to their special properties that cannot be found in alloys. Kevlar-Epoxy composite is one of the most widely used materials. In this paper, we analyze the heat transfer in rectangular fin
Mohsen Hajinejad Sorkhi +1 more
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Exact and Approximate Solutions for Some Classes of the Inhomogeneous Pantograph Equation
Axioms, 2023 The standard pantograph delay equation (SPDDE) is one of the famous delay models. This standard model is basically homogeneous in nature and it has been extensively studied in the literature. However, the studies on the general inhomogeneous form of such
A. A. Al Qarni
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EXACT INFLATIONARY SOLUTIONS [PDF]
International Journal of Modern Physics D, 1998 We present a new class of exact inflationary solutions for the evolution of a universe with spatial curvature, filled with a perfect fluid, a scalar field with potential V±(ϕ) = λ(ϕ2 ± δ2)2 and a cosmological constant Λ. With the V+(ϕ) potential and a negative cosmological constant, the scale factor experiments a graceful exit.
Piccinelli, Gabriella +2 more
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An elementary method for obtaining general solutions to systems of ordinary differential equations
Electronic Journal of Differential Equations, 2021 An analytical method is proposed for finding the general solution of a system of ordinary differential equations (ODEs). The general solution is expressed as a series which in some cases can be summed to give an expression in closed form.
Marianito R. Rodrigo
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Exact solutions in Chiral cosmology [PDF]
General Relativity and Gravitation, 2019 10 pages, no figures, title changed, version accepted for publication by Gen.
Andronikos Paliathanasis +2 more
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Exact formulae for certain integrals arising in potential theory [PDF]
, 1980 Exact formulae are derived for certain integrals arising in the solution of potential problems by integral equation ...
Hough, DM
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