18 papers
Self-Gravitating Magnetic Monopoles and Dyons in String-Inspired Models: Structure and Stability
Nick E. Mavromatos, Sarben Sarkar, Dionysios P. Theodosopoulos
We present classical magnetic--monopole (MM) and dyon solutions induced by global monopoles in string-inspired gravitational models. Although several ingredients of the constructio…
The -Effect from a Multimode Squeezed Graviton State
Nick E. Mavromatos, Sarben Sarkar
The -effect in entangled neutral-meson systems provides a sensitive probe of CPT violation induced by quantum-gravitational environments. In open quantum systems, interactions…
Probing String-Theory-Inspired Topologies of the Early Universe through CMB Temperature and Polarization Anisotropies
Nick E. Mavromatos, Miguel-Angel Sanchis-Lozano
TeV string-mass-scale strings have been excluded experimentally at colliders, as their effects have not been observed at the Large Hadron Collider (CERN). On the other hand, higher…
How Much Can Gravitons Be Squeezed?
Panagiotis Dorlis, Nick E. Mavromatos, Sarben Sarkar +1
Quantum Gravity remains elusive, largely because its observable effects are suppressed by powers of the Planck scale. Direct detection of single gravitons is widely believed to be…
Magnetic-monopole resummation justifies perturbatively calculated collider production cross sections
Jean Alexandre, Nick E. Mavromatos, Vasiliki A. Mitsou +1
A one-loop resummation scheme, inspired by Dyson-Schwinger (DS) formalism of strongly coupled quantum field theories, is applied to spin-1/2 magnetic monopoles (MMs), in the contex…
The most general four-derivative Unitary String Effective Action with Torsion and Stringy-Running-Vacuum-Model Inflation: Old ideas from a modern perspective
Nick E. Mavromatos, George Panagopoulos
The string-inspired running vacuum model (StRVM) of inflation is based on a Chern-Simons (CS) gravity effective action, in which the only four-spacetime-derivative-order term is a…