Results 1 to 10 of about 4,114,452 (292)
Horizon thermodynamics in fourth-order gravity
Physics Letters B, 2017 In the framework of horizon thermodynamics, the field equations of Einstein gravity and some other second-order gravities can be rewritten as the thermodynamic identity: dE=TdS−PdV.
Meng-Sen Ma
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Stability and square integrability of derivatives of solutions of nonlinear fourth order differential equations with delay [PDF]
Journal of Inequalities and Applications, 2017 In this paper, we give sufficient conditions for the boundedness, uniform asymptotic stability and square integrability of the solutions to a certain fourth order non-autonomous differential equations with delay by using Lyapunov’s second method.
Erdal Korkmaz
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Oscillation of Nonlinear Neutral Delay Difference Equations of Fourth Order
Mathematics, 2023 This paper focuses on the study of the oscillatory behavior of fourth-order nonlinear neutral delay difference equations. The authors use mathematical techniques, such as the Riccati substitution and comparison technique, to explore the regularity and ...
Ramasamy Vimala +5 more
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A fast and efficient Newton-type iterative scheme to find the sign of a matrix
AIMS Mathematics, 2023 This work proposes a new scheme under the umbrella of iteration methods to compute the sign of an invertible matrix. To this target, a review of the exiting solvers of the same type is given and then a new scheme is derived based on a multi-step Newton ...
Malik Zaka Ullah +5 more
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Fourth-order symplectic integration [PDF]
Physica D: Nonlinear Phenomena, 1990 Die Autoren behandeln die Integration der Hamiltonschen Gleichungen unter Anwendung einer expliziten Vierter-Ordnung-Methode. Diese bewahrt die Eigenschaft, daß eine zeitliche Entwicklung eines solchen Systems eine kanonische Transformation aus den Anfangsbedingungen bis zum Endzustand erhält.
Forest, E., Ruth, R.D.
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Oscillation Theorems for Nonlinear Differential Equations of Fourth-Order
Mathematics, 2020 We study the oscillatory behavior of a class of fourth-order differential equations and establish sufficient conditions for oscillation of a fourth-order differential equation with middle term.
Osama Moaaz +3 more
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Fourth-order supergravity [PDF]
Nuclear Physics B, 1986 Abstract Starting from a manifestly supersymmetric superfield formalism, we construct the lagrangian of fourth-order supergravity in component field form. The super-Gauss-Bonnet theorem can be used to eliminate one of the three terms in the superfield lagrangian. We verify the super-Gauss- Bonnet theorem explicitly or the bosonic part of the theory.
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Two maximum principles for a nonlinear fourth order equation from thin plate theory
Electronic Journal of Qualitative Theory of Differential Equations, 2014 We develop two maximum principles for a nonlinear equation of fourth order that arises in thin plate theory. As a consequence, we obtain uniqueness results for the corresponding fourth order boundary value problem under Navier boundary conditions as ...
Cristian-Paul Danet
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Bouncing Cosmology in Fourth-Order Gravity
Universe, 2022 The Big Bang initial singularity problem can be solved by means of bouncing solutions. In the context of extended theories of gravity, we will look for covariant effective actions whose field equations contain up to fourth-order derivatives of the metric
Marcello Miranda +3 more
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Rearrangements and fourth order equations [PDF]
Quarterly of Applied Mathematics, 2003 The paper contains a priori estimates for the deformation of plates and beams. In particular we investigate the “worst cases” for the maximum deformation depending on where a load is placed on a beam or plate. The methods of proof use rearrangement argument.
FERONE, VINCENZO, KAWOHL B.
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