29 citations · 158 across the 18 of their papers we have counts for
18 papers
Modified entropies, their corresponding Newtonian forces, potentials, and temperatures
Aldo Martínez-Merino, Octavio Obregón, Michael P. Ryan
Assuming the hypothesis of the entropic nature of gravity, we calculate generalized Newtonian forces, their associated potentials and field equations, when other, in general non-ex…
Newtonian black holes: Particle production, "Hawking" temperature, entropies and entropy field equations
Aldo Martínez-Merino, Octavio Obregón, Michael P. Ryan
Newtonian gravitation with some slight modifications, along with some highly simplified ideas from quantum field theory allow us to reproduce, at least at the level of back-of-the-…
Toward Supergravity Spectral Action
J. L. López, O. Obregón, M. P. Ryan +1
A spectral action of Euclidean supergravity is proposed. We calculate up to , the Seeley-Dewitt coefficients in the expansion of the spectral action associated to the supergra…
Quantum collapse of dust shells in 2+1 gravity
L. Ortíz, M. P. Ryan
This paper considers the quantum collapse of infinitesimally thin dust shells in 2+1 gravity. In 2+1 gravity a shell is no longer a sphere but a ring of matter. The classical equat…
Regular non-twisting S-branes
Octavio Obregon, Hernando Quevedo, Michael P. Ryan
We construct a family of time and angular dependent, regular S-brane solutions which corresponds to a simple analytical continuation of the Zipoy-Voorhees 4-dimensional vacuum spac…
The conformally invariant Laplace-Beltrami operator and factor ordering
Michael P. Ryan, Alexander V. Turbiner
In quantum mechanics the kinetic energy term for a single particle is usually written in the form of the Laplace-Beltrami operator. This operator is a factor ordering of the classi…