Symmetry and Integrability of Equations of Mathematical Physics − 2018



Volodymyr Fedorchuk (Ya.S. Pidstryhach Institute for Applied Problems of Mechanics and Mathematics of NAS of Ukraine, Lviv, Ukraine)

On some invariant solutions for the Euler–Lagrange–Born–Infeld equation

Abstract:
Let us consider the Euler–Lagrange–Born–Infeld equation of the form $$ \Box u\left(1-u_{\nu}u^{\nu}\right)+u^{\mu}u^{\nu}u_{\mu\nu}=0, $$ where $u=u(x), x=(x_0, x_1, x_2, x_3)\in M(1,3),$ $u_{\mu}\equiv\dfrac{\partial u}{\partial x^{\mu}},$ $u_{\mu\nu}\equiv\dfrac{\partial^2 u}{\partial x^{\mu}\partial x^{\nu}},$ $u^{\mu}=g^{\mu\nu}u_{\nu}, g_{\mu\nu}=(1,-1,-1,-1)\delta_{\mu\nu},$ $\mu,\nu=0,1,2,3,$ $\Box$ is the d'Alembert operator.

A connection between structural properties of low-dimensional ($\dim L \le3$) nonconjugate subalgebras of the Lie argebra of the generalized Poincaré group $P(1,4)$ and results of symmetry reduction for the Euler–Lagrange–Born–Infeld equation is studied.

In my talk I plan to present some invariant solutions for the Euler–Lagrange–Born–Infeld equation.

References:
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[13] Grundland A.M. and Hariton A., Algebraic aspects of the supersymmetric minimal surface equation, Symmetry, 2017, 9(12), 318; doi:10.3390/sym9120318.
[14] Fedorchuk V.M. and Fedorchuk V.I., On classification of the low-dimensional non-conjugate subalgebras of the Lie algebra of the Poincare group $P(1,4)$ (In Ukrainian), Proceedings of Institute of Mathematics of NAS of Ukraine, 3 (2006) 302–308.
[15] Fedorchuk V.M. and Fedorchuk V.I., On classification of symmetry reductions for the Eikonal equation, Symmetry, 2016, 8(6), 51; doi:10.3390/sym8060051.
[16] Fedorchuk V.M. and Fedorchuk V.I., On classification of symmetry reductions for partial differential equations, Collection of the works dedicated to 80th of anniversary of B.J. Ptashnyk, 241–255, Pidstryhach Institute for Applied Problems of Mechanics and Mathematics of NAS of Ukraine, Lviv, 2017.
[17] Fedorchuk V.M. and Fedorchuk V.I., Classification of Symmetry Reductions for the Eikonal Equation, Pidstryhach Institute for Applied Problems of Mechanics and Mathematics of National Academy of Sciences of Ukraine, Lviv, 2018. 176 pp.