4 papers
A local Lagrangian for MOND as modified inertia
Renato Costa, Guilherme Franzmann, Jonas P. Pereira
We propose a local Lagrangian for a point particle where its inertia part is modified in the regime of small accelerations. For the standard gravitational central force, it recover…
T-dual cosmological solutions in double field theory
Robert Brandenberger, Renato Costa, Guilherme Franzmann +1
We investigate the cosmological solutions coming from the double field theory equations of motion after coupling a matter source to them. Assuming constant dilaton and imposing the…
Are fast radio bursts generated by cosmic string cusps?
Renato Costa, Jake E. B. Gordin, Amanda Weltman
We revisit the idea that cosmic strings could source fast radio bursts by taking into account Lorentz boosts and a weaker assumption about the scaling law for the energy of particl…
Dual Space-Time and Nonsingular String Cosmology
Robert Brandenberger, Renato Costa, Guilherme Franzmann +1
Making use of the T-duality symmetry of superstring theory, and of the double geometry from Double Field Theory, we argue that cosmological singularities of a homogeneous and isotr…