338 citations
- National Research Institute of Astronomy and GeophysicsEG16 papers
- École de Technologie SupérieureCA6 papers
- Guilin University of Electronic TechnologyCN6 papers
- University of JeddahSA6 papers
- King Abdulaziz City for Science and TechnologySA5 papers
- Nihon UniversityJP5 papers
- University of Technology MalaysiaMY5 papers
- GLA UniversityIN4 papers
- Imam Mohammad ibn Saud Islamic UniversitySA4 papers
- Tunis El Manar UniversityTN4 papers
- Al Madinah International UniversityMY3 papers
- Centre National de la Recherche ScientifiqueFR3 papers
4 papers · 1 filter
A new topological perspective of expanding space-times with applications to cosmology
Nasr Ahmed, Anirudh Pradhan, F. Salama
We discuss the possible role of the Tietze extension theorem in providing a rigorous topological base to the expanding space-time in cosmology. A simple toy model has been introduc…
On the existence of deformations and dimensional reduction in wormholes and black holes
Nasr Ahmed, H. Rafat
The deformation retract is, by definition, a homotopy between a retraction and the identity map. We show that applying this topological concept to Ricci-flat wormholes/black holes…
The Coulomb potential in quantum mechanics revisited
A. A. Othman, M. de Montigny, F. Marsiglio
The procedure commonly used in textbooks for determining the eigenvalues and eigenstates for a particle in an attractive Coulomb potential is not symmetric in the way the boundary…
Bianchi Type- cosmology in gravity with
Nasr Ahmed, Anirudh Pradhan
A new class of cosmological models in modified theories of gravity proposed by Harko et al. (2011), where the gravitational Lagrangian is given by an arbitrary function o…