Symmetry vector fields and similarity solutions of a nonlinear field equation describing the relaxation to a maxwell distribution

1988 ◽  
Vol 27 (6) ◽  
pp. 717-723 ◽  
Author(s):  
N. Euler ◽  
P. G. L. Leach ◽  
F. M. Mahomed ◽  
W. -H. Steeb
1963 ◽  
Vol 4 (3) ◽  
pp. 334-338 ◽  
Author(s):  
D. D. Betts ◽  
H. Schiff ◽  
W. B. Strickfaden

2019 ◽  
Vol 16 (02) ◽  
pp. 1950032 ◽  
Author(s):  
Azadeh Naderifard ◽  
S. Reza Hejazi ◽  
Elham Dastranj ◽  
Ahmad Motamednezhad

In this paper, group analysis of the fourth-order time-fractional Burgers–Korteweg–de Vries (KdV) equation is considered. Geometric vector fields of Lie point symmetries of the equation are investigated and the corresponding optimal system is found. Similarity solutions of the equation are presented by using the obtained optimal system. Finally, a useful method called invariant subspaces is applied in order to find another solutions.


2000 ◽  
Vol 61 (4) ◽  
pp. R3299-R3302 ◽  
Author(s):  
Roberto Franzosi ◽  
Raoul Gatto ◽  
Giulio Pettini ◽  
Marco Pettini

1994 ◽  
Vol 35 (12) ◽  
pp. 6489-6497
Author(s):  
T. Moorhouse ◽  
R. S. Ward

2019 ◽  
Vol 150 (2) ◽  
pp. 841-870
Author(s):  
Alireza Khatib ◽  
Liliane A. Maia

AbstractWe consider the Null Mass nonlinear field equation (𝒫)$$\left\{ {\matrix{ {-\Delta u = f(u){\rm in}\;\;\Omega } \hfill \hfill \hfill \hfill \cr {u > 0} \hfill \hfill \hfill \hfill \hfill \hfill \hfill \hfill \hfill \hfill \hfill \hfill \hfill \hfill \hfill \hfill \hfill \hfill \cr {u \vert_{\partial \Omega } = 0} \cr } } \right.$$ where ${\open R}^N \setminus \Omega $ is a bounded regular domain. The existence of a bound state solution is established in situations where this problem does not have a ground state.


2002 ◽  
Vol 17 (20) ◽  
pp. 2765-2765 ◽  
Author(s):  
Y. ITIN

The obstruction for the existence of an energy-momentum tensor for the gravitational field in GR is connected with vanishing of first order invariants in (pseudo) Riemannian geometry. This specific geometric property is not valid in alternative geometrical structures1,2. A parallelizable differentiable 4D-manifold endowed with a class of smooth coframe fields ϑa is considered. A general 3-parameter class of global Lorentz invariant teleparallel models is considered. It includes a 1-parameter subclass of models with the Schwarzschild coframe solution (generalized teleparallel equivalent of gravity) 3. By introducing the notion of a 3-parameter conjugate field strength F linear in the strength Ca = dϑa the coframe Lagrangian is rewritten in the Maxwell-Yang-Mills form L = 1/2Fa ∧ Ca. The field equation turns out to have a form d * Fa = Ta completely similar to the Maxwell field equation. By applying the Noether procedure, the source 3-form Ta is shown to be connected with the diffeomorphism invariance of the Lagrangian. Thus the source Ta of the coframe field is interpreted as the total conserved energy-momentum current of the coframe field and matter4. The energy-momentum tensor is defined as a map of the module of current 3-forms into the module of vector fields 5. Thus an energy-momentum tensor for the coframe is defined in a diffeomorphism invariant and a translational covariant way. The total energy-momentum current of a system is conserved. Thus a redistribution of the energy-momentum current between material and coframe (gravity) field is possible in principle, unlike as in the standard GR. The result is: The standard GR has a neighborhood of viable models with the same Schwarzschild solutions. These models however have a better Lagrangian behavior and produce an invariant energy-momentum tensor.


1991 ◽  
Vol 60 (3) ◽  
pp. 1132-1133 ◽  
Author(s):  
N. Euler ◽  
W.-H. Steeb ◽  
P. Mulser

Sign in / Sign up

Export Citation Format

Share Document