5 papers
Interacting with the fifth dimension
Mark D. Roberts
Some new five dimensional minimal scalar-Einstein exact solutions are presented. These new solutions are tested against various criteria used to measure interaction with the fifth…
Stability of Poisson Equilibria and Hamiltonian Relative Equilibria by Energy Methods
George W. Patrick, Mark Roberts, Claudia Wulff
We develop a general stability theory for equilibrium points of Poisson dynamical systems and relative equilibria of Hamiltonian systems with symmetries, including several generali…
Second Variations of String Actions
Mark D. Roberts
A short article describing the derivation of the string deviation equation: .
A Generalized Higgs Model
Mark D. Roberts
The Higgs model is generalized so that in addition to the radial Higgs field there are fields which correspond to the themasy and entropy. The model is further generalized to inclu…
Spacetime Exterior to a Star: Against Asymptotic Flatness
Mark D. Roberts
In many circumstances the perfect fluid conservation equations can be directly integrated to give a Geometric-Thermodynamic equation: typically that the lapse is the reciprocal…