Results 11 to 20 of about 176 (26)

Recursion Operators and Tri-Hamiltonian Structure of the First Heavenly Equation of Pleba\'nski [PDF]

, 2016
We present first heavenly equation of Pleba\'nski in a two-component evolutionary form and obtain Lagrangian and Hamiltonian representations of this system.
Sheftel, Mikhail B., Yazıcı, Devrim
core   +1 more source

Generating potentials via difference equations

, 2006
The condition for pressure isotropy, for spherically symmetric gravitational fields with charged and uncharged matter, is reduced to a recurrence equation with variable, rational coefficients.
Debnath, Delgaty, Durgapal, Durgapal, Finch, Ivanov, John, Maharaj, Mak, Sharma, Stephani   +10 more
core   +1 more source

Partner symmetries and non-invariant solutions of four-dimensional heavenly equations [PDF]

, 2004
We extend our method of partner symmetries to the hyperbolic complex Monge-Amp\`ere equation and the second heavenly equation of Pleba\~nski. We show the existence of partner symmetries and derive the relations between them for both equations.
A A Malykh, Aliev A N, Atiyah M F, Boyer C P, Dunajski M, Goldblatt E, Ivanov I T, Levi D, M B Sheftel, Malykh A A, Malykh A A, Mason L J, Mason L J, Olver P, Plebañski J F, Y Nutku   +15 more
core   +1 more source

Exact Nonnull Wavelike Solutions to Gravity with Quadratic Lagrangians

, 1999
Solutions to gravity with quadratic Lagrangians are found for the simple case where the only nonconstant metric component is the lapse $N$ and the Riemann tensor takes the form $R^{t}_{.itj}=-k_{i}k_{j}, i,j=1,2,3$; thus these solutions depend on cross ...
Roberts, Mark D.
core   +1 more source

Method of group foliation, hodograph transformation and non-invariant solutions of the Boyer-Finley equation

, 2003
We present the method of group foliation for constructing non-invariant solutions of partial differential equations on an important example of the Boyer-Finley equation from the theory of gravitational instantons.
Sheftel, M. B.
core   +1 more source

Exact Fermi coordinates for a class of spacetimes

, 2009
We find exact Fermi coordinates for timelike geodesic observers for a class of spacetimes that includes anti-de Sitter spacetime, de Sitter spacetime, the constant density interior Schwarzschild spacetime with positive, zero, and negative cosmological ...
David Klein, O’Neill B., Peter Collas, Synge J. L.   +3 more
core   +1 more source

New anisotropic models from isotropic solutions

, 2005
We establish an algorithm that produces a new solution to the Einstein field equations, with an anisotropic matter distribution, from a given seed isotropic solution.
Bowers, Chaisi, Chaisi, Dev, Dev, Gokhroo, Herrera, Herrera, Ivanov, Maharaj, Maharaj, Mak, Mak, Rhoades, Saslaw, Saslaw, Sharma, Stephani, Wolfram   +18 more
core   +2 more sources

LRS Bianchi type-I cosmological model with constant deceleration parameter in $f(R,T)$ gravity

, 2017
A spatially homogeneous anisotropic LRS Bianchi type-I cosmological model is studied in $f(R,T)$ gravity with a special form of Hubble's parameter, which leads to constant deceleration parameter.
Bishi, Binaya K., Pacif, S. K. J., Sahoo, P. K., Singh, G. P.   +3 more
core   +1 more source

The Entropy of Lagrange-Finsler Spaces and Ricci Flows

, 2007
We formulate a statistical analogy of regular Lagrange mechanics and Finsler geometry derived from Grisha Perelman's functionals generalized for nonholonomic Ricci flows. There are elaborated explicit constructions when nonholonomically constrained flows
Antonelli, Bao, Bejancu, Cao, Hamilton, Miron, Miron R., Mrugala, Rapoport, Ruppeiner, Ruppeiner, Salamon, Sergiu I. Vacaru, Tsallis, Vacaru, Vacaru, Vacaru, Vacaru, Vacaru, Vacaru, Vacaru   +20 more
core   +4 more sources

Fractional Curve Flows and Solitonic Hierarchies in Gravity and Geometric Mechanics

, 2011
Methods from the geometry of nonholonomic manifolds and Lagrange-Finsler spaces are applied in fractional calculus with Caputo derivatives and for elaborating models of fractional gravity and fractional Lagrange mechanics.
Dumitru Baleanu, Gorenflo R., Kilbas A. A., Sergiu I. Vacaru   +3 more
core   +1 more source