Results 21 to 30 of about 8,147,434 (373)
ON THE GLOBAL EXISTENCE OF TIME [PDF]
International Journal of Modern Physics D, 2009 The global existence of time is often taken for granted but should instead be considered for investigation. Using the tools of global Lorentzian geometry the author shows that, under physically reasonable conditions, the impossibility of finding a global time implies the singularity of space–time.
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Global Existence for Nonlinear Diffusion Equations
Journal of Mathematical Analysis and Applications, 1995 The Dirichlet problem for degenerate reaction-diffusion-convection equations in space-dimension one is considered. Global existence of nonnegative solutions is studied. The role of convection in yielding global existence is analyzed in the special case when none of the three nonlinearities depends explicitly on \(x\) and \(t\).
Jeffrey R. Anderson, Kang Deng
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Existence of a Global Solution for a Viscoelastic System
Journal of Mathematical Analysis and Applications, 1998 The author considers the Cauchy problem for the viscoelastic system \[ v_t- u_x= 0,\quad u_t- f(v)_x+ ku= u_{xx} \] without the restriction that the initial data approach constants at infinity. Existence of unique classical solution is proved, including a priori estimates.
Yun‐guang Lu
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Existence of global strings coupled to gravity [PDF]
Physical Review D, 1989 We consider σ-model strings and U(1) global strings coupled to gravity and look for static solutions with whole cylinder symmetry. We prove that in both cases there are no regular spatially compact solutions. The U(1) global string admits no asymptotically well-behaved solutions, whereas cr model strings can be constructed under certain assumptions ...
Ruiz Ruiz, Fernando +2 more
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On a viscoelastic heat equation with logarithmic nonlinearity
Electronic Journal of Qualitative Theory of Differential Equations, 2022 This work deals with the following viscoelastic heat equations with logarithmic nonlinearity \begin{align*} u_t-\Delta u+\int_{0}^{t}g(t-s)\Delta u(s)ds=\vert u\vert^{p-2}u\ln\vert u\vert.
Nguyen Van Y, Nhan Le, Le Xuan Truong
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Global existence and stability for the modified Mullins–Sekerka and surface diffusion flow
Mathematics in Engineering, 2022 In this survey we present the state of the art about the asymptotic behavior and stability of the modified Mullins–Sekerka flow and the surface diffusion flow of smooth sets, mainly due to E. Acerbi, N. Fusco, V. Julin and M. Morini.
Serena Della Corte +2 more
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Global Existence Analysis of Cross-Diffusion Population Systems for Multiple Species [PDF]
, 2016 The existence of global-in-time weak solutions to reaction-cross-diffusion systems for an arbitrary number of competing population species is proved. The equations can be derived from an on-lattice random-walk model with general transition rates.
Xiuqing Chen, Esther S. Daus, A. Jüngel
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The derivative NLS equation: global existence with solitons [PDF]
, 2017 We extend the global existence result for the derivative NLS equation to the case when the initial datum includes a finite number of solitons. This is achieved by an application of the B\"{a}cklund transformation that removes a finite number of zeros of ...
Yusuke Shimabukuro +2 more
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Global Existence of Near-Affine Solutions to the Compressible Euler Equations [PDF]
Archive for Rational Mechanics and Analysis, 2017 We establish the global existence of solutions to the compressible Euler equations, in the case that a finite volume of ideal gas expands into a vacuum.
S. Shkoller, T. Sideris
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On the global existence for the Muskat problem
Journal of the European Mathematical Society, 2012 The Muskat problem models the dynamics of the interface between two incompressible immiscible fluids with different constant densities. In this work we prove three results. First we prove an L^2(\mathbb R) maximum principle, in the form of a new "log'' conservation law which is ...
D. Cordoba +3 more
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