Tags » Mathematical Physics

Cosmological Evolution and Exact Solutions in a Fourth-order Theory of Gravity [CL]

http://arxiv.org/abs/1701.04360

A fourth-order theory of gravity is considered which in terms of dynamics has the same degrees of freedom and number of constraints as those of scalar-tensor theories. 66 more words

Cosmology And Nongalactic Astrophysics

Research Fellow in Mathematical Physics @ Uni of Melbourne

Applications are invited to apply for a two year postdoctoral position, available from early 2017, to work in the School of Mathematics and Statistics of the University of Melbourne. 43 more words

Jobs

The structure of invariant tori in a 3D galactic potential [CL]

http://arxiv.org/abs/1009.1993

We study in detail the structure of phase space in the neighborhood of stable periodic orbits in a rotating 3D potential of galactic type. We have used the color and rotation method to investigate the properties of the invariant tori in the 4D spaces of section. 148 more words

Astrophysics Of Galaxies

Chains of rotational tori and filamentary structures close to high multiplicity periodic orbits in a 3D galactic potential [CL]

http://arxiv.org/abs/1103.3981

This paper discusses phase space structures encountered in the neighborhood of periodic orbits with high order multiplicity in a 3D autonomous Hamiltonian system with a potential of galactic type. 250 more words

Astrophysics Of Galaxies

The structure and evolution of confined tori near a Hamiltonian Hopf Bifurcation [CL]

http://arxiv.org/abs/1012.2463

We study the orbital behavior at the neighborhood of complex unstable periodic orbits in a 3D autonomous Hamiltonian system of galactic type. At a transition of a family of periodic orbits from stability to complex instability (also known as Hamiltonian Hopf Bifurcation) the four eigenvalues of the stable periodic orbits move out of the unit circle. 153 more words

Astrophysics Of Galaxies

Instabilities and stickiness in a 3D rotating galactic potential [CL]

http://arxiv.org/abs/1201.2108

We study the dynamics in the neighborhood of simple and double unstable periodic orbits in a rotating 3D autonomous Hamiltonian system of galactic type. In order to visualize the four dimensional spaces of section we use the method of color and rotation. 248 more words

Astrophysics Of Galaxies

Conservation laws and evolution schemes in geodesic, hydrodynamic and magnetohydrodynamic flows [CL]

http://arxiv.org/abs/1612.09308

Carter and Lichnerowicz have established that barotropic fluid flows are conformally geodesic and obey Hamilton’s principle. This variational approach can accommodate neutral, or charged and poorly conducting, fluids. 186 more words

High Energy Astrophysical Phenomena